diff --git a/ReadMe.txt b/ReadMe.txt
index da59e7b..f538943 100644
--- a/ReadMe.txt
+++ b/ReadMe.txt
@@ -58,8 +58,9 @@ LINKS
 
 CHANGES
 
-Version 2.7 (2022-09-XX)
+Version 2.7 (2023-07-XX)
 
+- Updated source code with Emu48 version 1.65+. This new version improve the serial communication.
 - Attempt to fix haptic feedback with Android 13 (API deprecation).
 - Patch the ROM files to prevent the calculator to sleep for HP38G, HP39G, HP40G, HP48SX and HP48GX.
 	There is an issue with this patch and the Flashcard for the HP49/50 because an already existing Flashcard embed the non patched ROM file,
diff --git a/app/CMakeLists.txt b/app/CMakeLists.txt
index 94c7423..5f61ea0 100644
--- a/app/CMakeLists.txt
+++ b/app/CMakeLists.txt
@@ -21,6 +21,14 @@ cmake_minimum_required(VERSION 3.4.1)
 
 #add_compile_options(-DNEW_WIN32_SOUND_ENGINE)
 
+# For the library LodePNG
+add_compile_options(-DLODEPNG_NO_COMPILE_ENCODER)
+add_compile_options(-DLODEPNG_NO_COMPILE_DISK)
+add_compile_options(-DLODEPNG_NO_COMPILE_ANCILLARY_CHUNKS)
+add_compile_options(-DLODEPNG_NO_COMPILE_ERROR_TEXT)
+add_compile_options(-DLODEPNG_NO_COMPILE_CPP)
+# add_compile_options(-DLODEPNG_NO_COMPILE_CRC) # Disabled to use new CRC function from lodepng.
+
 add_compile_options(-DEMUXX=48)
 
 if(CMAKE_BUILD_TYPE STREQUAL Release)
@@ -53,7 +61,7 @@ add_library( # Sets the name of the library.
         src/main/cpp/core/disrpl.c
 #        src/main/cpp/core/Emu48.c #-> To rewrite
         src/main/cpp/core/engine.c
-#        src/main/cpp/core/external.c # Removed in Emu48+ for Windows version 1.62+
+        src/main/cpp/core/external.c
         src/main/cpp/core/fetch.c
         src/main/cpp/core/files.c
         src/main/cpp/core/i28f160.c
@@ -66,7 +74,9 @@ add_library( # Sets the name of the library.
         src/main/cpp/core/mru.c
         src/main/cpp/core/opcodes.c
         src/main/cpp/core/pch.c
+#		src/main/cpp/core/pngcrc.c # Disabled to use new CRC function from lodepng.
         src/main/cpp/core/redeye.c
+		src/main/cpp/core/romcrc.c
         src/main/cpp/core/rpl.c
         src/main/cpp/core/serial.c
         src/main/cpp/core/settings.c
@@ -77,6 +87,7 @@ add_library( # Sets the name of the library.
         src/main/cpp/core/timer.c
 #        src/main/cpp/core/udp.c
 
+
         src/main/cpp/win32-layer.c
         src/main/cpp/android-layer.c
         src/main/cpp/android-emu.c # Emu48.c rewrite
diff --git a/app/src/main/assets/ReadMe.txt b/app/src/main/assets/ReadMe.txt
index ad4795c..6afc755 100644
--- a/app/src/main/assets/ReadMe.txt
+++ b/app/src/main/assets/ReadMe.txt
@@ -58,6 +58,15 @@ LINKS
 
 CHANGES
 
+Version 2.7 (2023-07-XX)
+
+- Updated source code with Emu48 version 1.65+. This new version improve the serial communication.
+- Attempt to fix haptic feedback with Android 13 (API deprecation).
+- Patch the ROM files to prevent the calculator to sleep for HP38G, HP39G, HP40G, HP48SX and HP48GX.
+	There is an issue with this patch and the Flashcard for the HP49/50 because an already existing Flashcard embed the non patched ROM file,
+	and the CRC check failed and make a CPU reset!
+- Fix a potential crash about the permission to access the files.
+
 Version 2.6 (2022-08-19)
 
 - Updated source code from Eric Rechlin's Emu48 version 1.64+ that was merged from Christoph Gießelink's Emu48 version 1.65. This new version improve the serial communication.
diff --git a/app/src/main/assets/calculators/CP_48G3.KML b/app/src/main/assets/calculators/CP_48G3.KML
index e692ab8..5fabd72 100644
--- a/app/src/main/assets/calculators/CP_48G3.KML
+++ b/app/src/main/assets/calculators/CP_48G3.KML
@@ -21,7 +21,7 @@ Global
 	Author "Casey Patterson && Sebastien Carlier"
 	Model  "G"
 	Rom    "rom.48g"
-	Patch  "PATCHES.48"
+	Patch  "patch.48"
 	Bitmap "cp_48g3.bmp"
 	Debug  0
 End
diff --git a/app/src/main/assets/calculators/CP_48S3.KML b/app/src/main/assets/calculators/CP_48S3.KML
index be75173..de380ff 100644
--- a/app/src/main/assets/calculators/CP_48S3.KML
+++ b/app/src/main/assets/calculators/CP_48S3.KML
@@ -13,7 +13,7 @@ Global
 	Author "Casey Patterson"
 	Model   "S"
 	Rom    "rom.48s"
-	Patch  "PATCHES.48"
+	Patch  "patch.48"
 	Bitmap "cp_48s3.bmp"
 	Debug  0
 End
diff --git a/app/src/main/assets/calculators/DEFAUL38.KML b/app/src/main/assets/calculators/DEFAUL38.KML
index fea2a60..78b3b87 100644
--- a/app/src/main/assets/calculators/DEFAUL38.KML
+++ b/app/src/main/assets/calculators/DEFAUL38.KML
@@ -9,7 +9,7 @@ Global
 	Author "Christoph Giesselink"
 	Model  "A"
 	Rom    "rom.38g"
-	Patch  "PATCHES.38G"
+	Patch  "patch.38g"
 	Debug  0
 	Bitmap "DEFAUL38.BMP"
 End
diff --git a/app/src/main/assets/calculators/DEFAULTG.KML b/app/src/main/assets/calculators/DEFAULTG.KML
index a02b128..2c9d6f2 100644
--- a/app/src/main/assets/calculators/DEFAULTG.KML
+++ b/app/src/main/assets/calculators/DEFAULTG.KML
@@ -3,7 +3,7 @@ Global
 	Author "Sebastien Carlier"
 	Model   "G"
 	Rom    "rom.48g"
-	Patch  "PATCHES.48"
+	Patch  "patch.48"
 	Debug  0
 	Bitmap "DEFAULTG.BMP"
 End
diff --git a/app/src/main/assets/calculators/DEFAULTS.KML b/app/src/main/assets/calculators/DEFAULTS.KML
index 7745dcd..237fb00 100644
--- a/app/src/main/assets/calculators/DEFAULTS.KML
+++ b/app/src/main/assets/calculators/DEFAULTS.KML
@@ -3,7 +3,7 @@ Global
 	Author "Sebastien Carlier"
 	Model   "S"
 	Rom    "rom.48s"
-	Patch  "PATCHES.48"
+	Patch  "patch.48"
 	Debug  0
 	Bitmap "DEFAULTS.BMP"
 End
diff --git a/app/src/main/assets/calculators/FLOAT_GX.KML b/app/src/main/assets/calculators/FLOAT_GX.KML
index 50a7126..1492df8 100644
--- a/app/src/main/assets/calculators/FLOAT_GX.KML
+++ b/app/src/main/assets/calculators/FLOAT_GX.KML
@@ -13,7 +13,7 @@ Global
 	Author "Casey Patterson"
 	Model   "G"
 	Rom    "rom.48g"
-	Patch  "PATCHES.48"
+	Patch  "patch.48"
 	Debug  0
 	Bitmap "float_gx.bmp"
 End
diff --git a/app/src/main/assets/calculators/JEMAC.KML b/app/src/main/assets/calculators/JEMAC.KML
index 60ae714..f0fa2ef 100644
--- a/app/src/main/assets/calculators/JEMAC.KML
+++ b/app/src/main/assets/calculators/JEMAC.KML
@@ -3,7 +3,7 @@ Global
 	Author "Jeffery L. McMahan"
 	Model  "G"
 	Rom    "rom.48g"
-	Patch  "PATCHES.48"
+	Patch  "patch.48"
 	Bitmap "jemac.bmp"
 	Debug  0
 End
diff --git a/app/src/main/assets/calculators/Wombat3 48GX.kml b/app/src/main/assets/calculators/Wombat3 48GX.kml
index e579a45..62722c0 100644
--- a/app/src/main/assets/calculators/Wombat3 48GX.kml	
+++ b/app/src/main/assets/calculators/Wombat3 48GX.kml	
@@ -10,7 +10,7 @@ Global
 	Hardware "Yorke"
 	Model    "G"
 	Rom      "rom.48g"
-	Patch    "PATCHES.48"
+	Patch    "patch.48"
 	Bitmap   "Wombat3 48GX.bmp"
 	Debug    0
 End
diff --git a/app/src/main/assets/calculators/Wombat3 48SX.kml b/app/src/main/assets/calculators/Wombat3 48SX.kml
index 0cdfa0b..3ffacae 100644
--- a/app/src/main/assets/calculators/Wombat3 48SX.kml	
+++ b/app/src/main/assets/calculators/Wombat3 48SX.kml	
@@ -10,7 +10,7 @@ Global
 	Hardware "Yorke"
 	Model    "S"
 	Rom      "rom.48s"
-	Patch    "PATCHES.48"
+	Patch    "patch.48"
 	Bitmap   "Wombat3 48SX.bmp"
 	Debug    0
 End
diff --git a/app/src/main/assets/calculators/calypso2k.kml b/app/src/main/assets/calculators/calypso2k.kml
index ce6b4b9..91587ce 100644
--- a/app/src/main/assets/calculators/calypso2k.kml
+++ b/app/src/main/assets/calculators/calypso2k.kml
@@ -11,7 +11,7 @@ Global
 	Model  "Q"
 	Class  50
 	Rom    "rom.49g"
-	Patch  "PATCHES.49G"
+	Patch  "patch.49g"
 	Bitmap "calypso2k.png"
 	Color  0 0 0 0
 	#Scale 3 9
diff --git a/app/src/main/assets/calculators/calypso4k.kml b/app/src/main/assets/calculators/calypso4k.kml
index af1eec8..a1a1a96 100644
--- a/app/src/main/assets/calculators/calypso4k.kml
+++ b/app/src/main/assets/calculators/calypso4k.kml
@@ -11,7 +11,7 @@ Global
 	Model  "Q"
 	Class  50
 	Rom    "rom.49g"
-	Patch  "PATCHES.49G"
+	Patch  "patch.49g"
 	Bitmap "calypso4k.png"
 	Color  0 0 0 0
 	#Scale 3 18
diff --git a/app/src/main/assets/calculators/PATCHES.38G b/app/src/main/assets/calculators/patch.38g
similarity index 100%
rename from app/src/main/assets/calculators/PATCHES.38G
rename to app/src/main/assets/calculators/patch.38g
diff --git a/app/src/main/assets/calculators/PATCHES.39G b/app/src/main/assets/calculators/patch.39g
similarity index 100%
rename from app/src/main/assets/calculators/PATCHES.39G
rename to app/src/main/assets/calculators/patch.39g
diff --git a/app/src/main/assets/calculators/PATCHES.48 b/app/src/main/assets/calculators/patch.48
similarity index 100%
rename from app/src/main/assets/calculators/PATCHES.48
rename to app/src/main/assets/calculators/patch.48
diff --git a/app/src/main/assets/calculators/PATCHES.49G b/app/src/main/assets/calculators/patch.49g
similarity index 100%
rename from app/src/main/assets/calculators/PATCHES.49G
rename to app/src/main/assets/calculators/patch.49g
diff --git a/app/src/main/assets/calculators/real38g-l.kml b/app/src/main/assets/calculators/real38g-l.kml
index 3e230b1..742e023 100644
--- a/app/src/main/assets/calculators/real38g-l.kml
+++ b/app/src/main/assets/calculators/real38g-l.kml
@@ -15,7 +15,7 @@ Global
 	Author "Eric Rechlin"
 	Model  "6" # 6 for 64K RAM, A for 32K RAM
 	Rom    "rom.38g"
-	Patch  "PATCHES.38G"
+	Patch  "patch.38g"
 	Bitmap "real38g-l.png"
 	Icon   "38g.ico"
 	Color  0 190 190 190
diff --git a/app/src/main/assets/calculators/real38g-lc.kml b/app/src/main/assets/calculators/real38g-lc.kml
index 83c5c0d..4c3a36c 100644
--- a/app/src/main/assets/calculators/real38g-lc.kml
+++ b/app/src/main/assets/calculators/real38g-lc.kml
@@ -15,7 +15,7 @@ Global
 	Author "Eric Rechlin"
 	Model  "6" # 6 for 64K RAM, A for 32K RAM
 	Rom    "rom.38g"
-	Patch  "PATCHES.38G"
+	Patch  "patch.38g"
 	Bitmap "real38g-lc.png"
 	Icon   "38g.ico"
 	Color  0 190 190 190
diff --git a/app/src/main/assets/calculators/real39g-l.kml b/app/src/main/assets/calculators/real39g-l.kml
index 8a0a292..74cc341 100644
--- a/app/src/main/assets/calculators/real39g-l.kml
+++ b/app/src/main/assets/calculators/real39g-l.kml
@@ -14,7 +14,7 @@ Global
 	Model  "E"
 	Class  39
 	Rom    "rom.39g"
-	Patch  "PATCHES.39G"
+	Patch  "patch.39g"
 	Bitmap "real39g-l.png"
 	Icon   "39g.ico"
 	Color  0 190 190 190
diff --git a/app/src/main/assets/calculators/real39g-lc.kml b/app/src/main/assets/calculators/real39g-lc.kml
index d52fb7b..637e419 100644
--- a/app/src/main/assets/calculators/real39g-lc.kml
+++ b/app/src/main/assets/calculators/real39g-lc.kml
@@ -14,7 +14,7 @@ Global
 	Model  "E"
 	Class  39
 	Rom    "rom.39g"
-	Patch  "PATCHES.39G"
+	Patch  "patch.39g"
 	Bitmap "real39g-lc.png"
 	Icon   "39g.ico"
 	Color  0 190 190 190
diff --git a/app/src/main/assets/calculators/real39gp-l.kml b/app/src/main/assets/calculators/real39gp-l.kml
index fd25166..49b8241 100644
--- a/app/src/main/assets/calculators/real39gp-l.kml
+++ b/app/src/main/assets/calculators/real39gp-l.kml
@@ -14,7 +14,7 @@ Global
 	Model  "E"
 	Class  39
 	Rom    "rom.39g"
-	Patch  "PATCHES.39G"
+	Patch  "patch.39g"
 	Bitmap "real39gp-l.png"
 	Icon   "39gp.ico"
 	Color  0 190 190 190
diff --git a/app/src/main/assets/calculators/real39gp-lc.kml b/app/src/main/assets/calculators/real39gp-lc.kml
index 3d0b87f..9503310 100644
--- a/app/src/main/assets/calculators/real39gp-lc.kml
+++ b/app/src/main/assets/calculators/real39gp-lc.kml
@@ -14,7 +14,7 @@ Global
 	Model  "E"
 	Class  39
 	Rom    "rom.39g"
-	Patch  "PATCHES.39G"
+	Patch  "patch.39g"
 	Bitmap "real39gp-lc.png"
 	Icon   "39gp.ico"
 	Color  0 190 190 190
diff --git a/app/src/main/assets/calculators/real39gs-l.kml b/app/src/main/assets/calculators/real39gs-l.kml
index ea34659..9113e19 100644
--- a/app/src/main/assets/calculators/real39gs-l.kml
+++ b/app/src/main/assets/calculators/real39gs-l.kml
@@ -14,7 +14,7 @@ Global
 	Model  "E"
 	Class  39
 	Rom    "rom.39g"
-	Patch  "PATCHES.39G"
+	Patch  "patch.39g"
 	Bitmap "real39gs-l.png"
 	Icon   "39gs.ico"
 	Color  0 190 190 190
diff --git a/app/src/main/assets/calculators/real39gs-lc.kml b/app/src/main/assets/calculators/real39gs-lc.kml
index 5a32d5d..836686b 100644
--- a/app/src/main/assets/calculators/real39gs-lc.kml
+++ b/app/src/main/assets/calculators/real39gs-lc.kml
@@ -14,7 +14,7 @@ Global
 	Model  "E"
 	Class  39
 	Rom    "rom.39g"
-	Patch  "PATCHES.39G"
+	Patch  "patch.39g"
 	Bitmap "real39gs-lc.png"
 	Icon   "39gs.ico"
 	Color  0 190 190 190
diff --git a/app/src/main/assets/calculators/real40g-l.kml b/app/src/main/assets/calculators/real40g-l.kml
index 4c91595..7c84604 100644
--- a/app/src/main/assets/calculators/real40g-l.kml
+++ b/app/src/main/assets/calculators/real40g-l.kml
@@ -14,7 +14,7 @@ Global
 	Model  "E"
 	Class  40
 	Rom    "rom.39g"
-	Patch  "PATCHES.39G"
+	Patch  "patch.39g"
 	Bitmap "real40g-l.png"
 	Icon   "39g.ico"
 	Color  0 190 190 190
diff --git a/app/src/main/assets/calculators/real40g-lc.kml b/app/src/main/assets/calculators/real40g-lc.kml
index a07dfae..b7295b3 100644
--- a/app/src/main/assets/calculators/real40g-lc.kml
+++ b/app/src/main/assets/calculators/real40g-lc.kml
@@ -14,7 +14,7 @@ Global
 	Model  "E"
 	Class  40
 	Rom    "rom.39g"
-	Patch  "PATCHES.39G"
+	Patch  "patch.39g"
 	Bitmap "real39g-lc.png"
 	Icon   "40g.ico"
 	Color  0 190 190 190
diff --git a/app/src/main/assets/calculators/real40gs-l.kml b/app/src/main/assets/calculators/real40gs-l.kml
index 4491319..164e776 100644
--- a/app/src/main/assets/calculators/real40gs-l.kml
+++ b/app/src/main/assets/calculators/real40gs-l.kml
@@ -14,7 +14,7 @@ Global
 	Model  "E"
 	Class  40
 	Rom    "rom.39g"
-	Patch  "PATCHES.39G"
+	Patch  "patch.39g"
 	Bitmap "real40gs-l.png"
 	Icon   "40gs.ico"
 	Color  0 190 190 190
diff --git a/app/src/main/assets/calculators/real40gs-lc.kml b/app/src/main/assets/calculators/real40gs-lc.kml
index de7ac63..2c8ffd9 100644
--- a/app/src/main/assets/calculators/real40gs-lc.kml
+++ b/app/src/main/assets/calculators/real40gs-lc.kml
@@ -14,7 +14,7 @@ Global
 	Model  "E"
 	Class  40
 	Rom    "rom.39g"
-	Patch  "PATCHES.39G"
+	Patch  "patch.39g"
 	Bitmap "real40gs-lc.png"
 	Icon   "40gs.ico"
 	Color  0 190 190 190
diff --git a/app/src/main/assets/calculators/real48gii-l.kml b/app/src/main/assets/calculators/real48gii-l.kml
index 5a08136..2b97566 100644
--- a/app/src/main/assets/calculators/real48gii-l.kml
+++ b/app/src/main/assets/calculators/real48gii-l.kml
@@ -14,6 +14,7 @@ Global
 	Author "Eric Rechlin"
 	Model  "2"
 	Rom    "rom.49g"
+	Patch  "patch.49g"
 	Bitmap "real48gii-l.png"
 	Icon   "48gii.ico"
 	Color  0 190 190 190
diff --git a/app/src/main/assets/calculators/real48gii-lc.kml b/app/src/main/assets/calculators/real48gii-lc.kml
index f1355c5..a38e3c4 100644
--- a/app/src/main/assets/calculators/real48gii-lc.kml
+++ b/app/src/main/assets/calculators/real48gii-lc.kml
@@ -14,6 +14,7 @@ Global
 	Author "Eric Rechlin"
 	Model  "2"
 	Rom    "rom.49g"
+	Patch  "patch.49g"
 	Bitmap "real48gii-lc.png"
 	Icon   "48gii.ico"
 	Color  0 190 190 190
diff --git a/app/src/main/assets/calculators/real48gx-l.kml b/app/src/main/assets/calculators/real48gx-l.kml
index ab155dd..7f9cc82 100644
--- a/app/src/main/assets/calculators/real48gx-l.kml
+++ b/app/src/main/assets/calculators/real48gx-l.kml
@@ -14,7 +14,7 @@ Global
 	Author "Eric Rechlin"
 	Model  "G"
 	Rom    "rom.48g"
-	Patch  "PATCHES.48"
+	Patch  "patch.48"
 	Bitmap "real48gx-l.png"
 	Icon   "48gx.ico"
 	Color  0 190 190 190
diff --git a/app/src/main/assets/calculators/real48gx-lc.kml b/app/src/main/assets/calculators/real48gx-lc.kml
index 1af6756..36f7873 100644
--- a/app/src/main/assets/calculators/real48gx-lc.kml
+++ b/app/src/main/assets/calculators/real48gx-lc.kml
@@ -14,7 +14,7 @@ Global
 	Author "Eric Rechlin"
 	Model  "G"
 	Rom    "rom.48g"
-	Patch  "PATCHES.48"
+	Patch  "patch.48"
 	Bitmap "real48gx-lc.png"
 	Icon   "48gx.ico"
 	Color  0 190 190 190
diff --git a/app/src/main/assets/calculators/real48sx-l.kml b/app/src/main/assets/calculators/real48sx-l.kml
index 6782fef..c9cf4b7 100644
--- a/app/src/main/assets/calculators/real48sx-l.kml
+++ b/app/src/main/assets/calculators/real48sx-l.kml
@@ -14,7 +14,7 @@ Global
 	Author "Eric Rechlin"
 	Model  "S"
 	Rom    "rom.48s"
-	Patch  "PATCHES.48"
+	Patch  "patch.48"
 	Bitmap "real48sx-l.png"
 	Icon   "48sx.ico"
 	Color  0 190 190 190
diff --git a/app/src/main/assets/calculators/real48sx-lc.kml b/app/src/main/assets/calculators/real48sx-lc.kml
index 523c186..6039569 100644
--- a/app/src/main/assets/calculators/real48sx-lc.kml
+++ b/app/src/main/assets/calculators/real48sx-lc.kml
@@ -14,7 +14,7 @@ Global
 	Author "Eric Rechlin"
 	Model  "S"
 	Rom    "rom.48s"
-	Patch  "PATCHES.48"
+	Patch  "patch.48"
 	Bitmap "real48sx-lc.png"
 	Icon   "48sx.ico"
 	Color  0 190 190 190
diff --git a/app/src/main/assets/calculators/real49g-l.kml b/app/src/main/assets/calculators/real49g-l.kml
index a3cb173..3fd6d47 100644
--- a/app/src/main/assets/calculators/real49g-l.kml
+++ b/app/src/main/assets/calculators/real49g-l.kml
@@ -14,6 +14,7 @@ Global
 	Author "Eric Rechlin"
 	Model  "X"
 	Rom    "rom.49g"
+	Patch  "patch.49g"
 	Bitmap "real49g-l.png"
 	Icon   "49g.ico"
 	Color  0 190 190 190
diff --git a/app/src/main/assets/calculators/real49g-lc.kml b/app/src/main/assets/calculators/real49g-lc.kml
index c8bbb9c..a99af4e 100644
--- a/app/src/main/assets/calculators/real49g-lc.kml
+++ b/app/src/main/assets/calculators/real49g-lc.kml
@@ -14,6 +14,7 @@ Global
 	Author "Eric Rechlin"
 	Model  "X"
 	Rom    "rom.49g"
+	Patch  "patch.49g"
 	Bitmap "real49g-lc.png"
 	Icon   "49g.ico"
 	Color  0 190 190 190
diff --git a/app/src/main/assets/calculators/real49gp-l.kml b/app/src/main/assets/calculators/real49gp-l.kml
index a4e1d2b..76db014 100644
--- a/app/src/main/assets/calculators/real49gp-l.kml
+++ b/app/src/main/assets/calculators/real49gp-l.kml
@@ -14,6 +14,7 @@ Global
 	Author "Eric Rechlin"
 	Model  "Q"
 	Rom    "rom.49g"
+	Patch  "patch.49g"
 	Bitmap "real49gp-l.png"
 	Icon   "49gp.ico"
 	Color  0 190 190 190
diff --git a/app/src/main/assets/calculators/real49gp-lc.kml b/app/src/main/assets/calculators/real49gp-lc.kml
index 1e656cf..5e463f5 100644
--- a/app/src/main/assets/calculators/real49gp-lc.kml
+++ b/app/src/main/assets/calculators/real49gp-lc.kml
@@ -14,6 +14,7 @@ Global
 	Author "Eric Rechlin"
 	Model  "Q"
 	Rom    "rom.49g"
+	Patch  "patch.49g"
 	Bitmap "real49gp-lc.png"
 	Icon   "49gp.ico"
 	Color  0 190 190 190
diff --git a/app/src/main/assets/calculators/real50g-blue-l.kml b/app/src/main/assets/calculators/real50g-blue-l.kml
index 8637564..f9ca676 100644
--- a/app/src/main/assets/calculators/real50g-blue-l.kml
+++ b/app/src/main/assets/calculators/real50g-blue-l.kml
@@ -14,6 +14,7 @@ Global
 	Model  "Q"
 	Class  50
 	Rom    "rom.49g"
+	Patch  "patch.49g"
 	Bitmap "real50g-blue-l.png"
 	Icon   "50g.ico"
 	Color  0 190 190 190
diff --git a/app/src/main/assets/calculators/real50g-blue-lc.kml b/app/src/main/assets/calculators/real50g-blue-lc.kml
index 3a40fd5..70bc428 100644
--- a/app/src/main/assets/calculators/real50g-blue-lc.kml
+++ b/app/src/main/assets/calculators/real50g-blue-lc.kml
@@ -14,6 +14,7 @@ Global
 	Model  "Q"
 	Class  50
 	Rom    "rom.49g"
+	Patch  "patch.49g"
 	Bitmap "real50g-blue-lc.png"
 	Icon   "50g.ico"
 	Color  0 190 190 190
diff --git a/app/src/main/assets/calculators/real50g-l.kml b/app/src/main/assets/calculators/real50g-l.kml
index 22e59c8..7e15fb3 100644
--- a/app/src/main/assets/calculators/real50g-l.kml
+++ b/app/src/main/assets/calculators/real50g-l.kml
@@ -15,6 +15,7 @@ Global
 	Model  "Q"
 	Class  50
 	Rom    "rom.49g"
+	Patch  "patch.49g"
 	Bitmap "real50g-l.png"
 	Icon   "50g.ico"
 	Color  0 190 190 190
diff --git a/app/src/main/assets/calculators/real50g-lc.kml b/app/src/main/assets/calculators/real50g-lc.kml
index 36140dc..a963c92 100644
--- a/app/src/main/assets/calculators/real50g-lc.kml
+++ b/app/src/main/assets/calculators/real50g-lc.kml
@@ -15,6 +15,7 @@ Global
 	Model  "Q"
 	Class  50
 	Rom    "rom.49g"
+	Patch  "patch.49g"
 	Bitmap "real50g-lc.png"
 	Icon   "50g.ico"
 	Color  0 190 190 190
diff --git a/app/src/main/cpp/core/Emu48.c b/app/src/main/cpp/core/Emu48.c
index 57ed1c6..fe045f6 100644
--- a/app/src/main/cpp/core/Emu48.c
+++ b/app/src/main/cpp/core/Emu48.c
@@ -13,7 +13,7 @@
 #include "kml.h"
 #include "debugger.h"
 
-#define VERSION   "1.64+"
+#define VERSION   "1.65+"
 
 #ifdef _DEBUG
 LPCTSTR szNoTitle = _T("Emu48 ")_T(VERSION)_T(" Debug");
@@ -2042,19 +2042,19 @@ LRESULT CALLBACK MainWndProc(HWND hWindow, UINT uMsg, WPARAM wParam, LPARAM lPar
 
 int WINAPI WinMain(HINSTANCE hInst, HINSTANCE hPrevInst, LPSTR lpCmdLine, int nCmdShow)
 {
-	typedef DWORD (WINAPI *LPFN_STIP)(HANDLE hThread,DWORD dwIdealProcessor);
-
 	MSG msg;
 	WNDCLASS wc;
 	ATOM classAtom;
 	RECT rectWindow;
 	HACCEL hAccel;
 	DWORD dwThreadId;
-	LPFN_STIP fnSetThreadIdealProcessor;
 	DWORD dwProcessor;
 	HSZ hszService, hszTopic;				// variables for DDE server
 	LPTSTR lpFilePart;
 
+	// module handle to kernel32
+	const HMODULE hmKernel32 = GetModuleHandle(_T("kernel32"));
+
 	// enable memory leak detection
 	_CrtSetDbgFlag(_CRTDBG_ALLOC_MEM_DF | _CRTDBG_LEAK_CHECK_DF);
 
@@ -2147,6 +2147,26 @@ int WINAPI WinMain(HINSTANCE hInst, HINSTANCE hPrevInst, LPSTR lpCmdLine, int nC
 		return 0;							// quit program
 	}
 
+	// disable TIMER_RESOLUTION throttling for Windows 11 and later
+	{
+		typedef const BOOL(WINAPI* LPFN_SPI)(HANDLE hProcess,INT ProcessInformationClass,LPVOID ProcessInformation,DWORD ProcessInformationSize);
+
+		// SetProcessInformation() is available since Windows 8, PROCESS_POWER_THROTTLING_IGNORE_TIMER_RESOLUTION since Windows 11
+		LPFN_SPI fnSetProcessInformation = (LPFN_SPI) GetProcAddress(hmKernel32, "SetProcessInformation");
+
+		if (fnSetProcessInformation != NULL)			// running on Windows 8 or later 
+		{
+			PROCESS_POWER_THROTTLING_STATE Ppts;
+
+			ZeroMemory(&Ppts,sizeof(Ppts));
+			Ppts.Version = PROCESS_POWER_THROTTLING_CURRENT_VERSION;
+			Ppts.ControlMask = PROCESS_POWER_THROTTLING_IGNORE_TIMER_RESOLUTION;
+
+			// don't check for success, success only on Windoes 11 and later
+			fnSetProcessInformation(GetCurrentProcess(),ProcessPowerThrottling,&Ppts,sizeof(Ppts));
+		}
+	}
+
 	// Create window
 	rectWindow.left   = 0;
 	rectWindow.top    = 0;
@@ -2197,15 +2217,29 @@ int WINAPI WinMain(HINSTANCE hInst, HINSTANCE hPrevInst, LPSTR lpCmdLine, int nC
 		return FALSE;
 	}
 
-	// SetThreadIdealProcessor() is available since Windows NT4.0
-	fnSetThreadIdealProcessor = (LPFN_STIP) GetProcAddress(GetModuleHandle(_T("kernel32")),
-														   "SetThreadIdealProcessor");
+	// get processor for Saturn CPU thread
+	{
+		// GetCurrentProcessorNumber() is available since Windows Vista
+		typedef const DWORD (WINAPI *LPFN_GCPN)(VOID);
+		LPFN_GCPN fnGetCurrentProcessorNumber = (LPFN_GCPN) GetProcAddress(hmKernel32,"GetCurrentProcessorNumber");
 
-	// bind Saturn CPU emulation thread to current ideal processor
-	dwProcessor = (fnSetThreadIdealProcessor != NULL)					// running on NT4.0 or later
-				? fnSetThreadIdealProcessor(hThread,MAXIMUM_PROCESSORS)	// get ideal processor no.
-				: 0;													// select 1st processor
+		if (fnGetCurrentProcessorNumber != NULL)								// running on Vista or later
+		{
+			dwProcessor = fnGetCurrentProcessorNumber();						// get current processor number
+		}
+		else
+		{
+			// SetThreadIdealProcessor() is available since Windows NT4.0
+			typedef const DWORD (WINAPI *LPFN_STIP)(HANDLE hThread,DWORD dwIdealProcessor);
+			LPFN_STIP fnSetThreadIdealProcessor = (LPFN_STIP) GetProcAddress(hmKernel32,"SetThreadIdealProcessor");
 
+			dwProcessor = (fnSetThreadIdealProcessor != NULL)					// running on NT4.0 or later
+						? fnSetThreadIdealProcessor(hThread,MAXIMUM_PROCESSORS)	// get ideal processor no.
+						: 0;													// select 1st processor
+		}
+	}
+
+	// bind Saturn CPU emulation thread to selected processor
 	// on multiprocessor machines for QueryPerformanceCounter()
 	VERIFY(SetThreadAffinityMask(hThread,(DWORD_PTR) (1 << dwProcessor)));
 	ResumeThread(hThread);					// start thread
diff --git a/app/src/main/cpp/core/Emu48.h b/app/src/main/cpp/core/Emu48.h
index 1a4287c..26eb81e 100644
--- a/app/src/main/cpp/core/Emu48.h
+++ b/app/src/main/cpp/core/Emu48.h
@@ -8,6 +8,8 @@
  */
 #include "types.h"
 
+#define	_KB(a)			((a)*2*1024)
+
 #define HARDWARE		"Yorke"				// emulator hardware
 #define MODELS			"26AEGPQSX"			// valid calculator models
 #define APPLEHARD		"2PQ"				// Apple platform calculator models
@@ -72,6 +74,9 @@ enum MMUMAP { M_IO, M_ROM, M_RAM, M_P1, M_P2, M_BS };
 // values for disassembler memory mapping modes
 enum MEM_MAPPING { MEM_MMU, MEM_NCE1, MEM_NCE2, MEM_CE1, MEM_CE2, MEM_NCE3 };
 
+// Kermit CRC calculation
+static __inline WORD UpCRC(WORD wCRC, BYTE nib) { return (wCRC >> 4) ^ (((wCRC ^ nib) & 0xf) * 0x1081); }
+
 // Emu48.c
 extern HPALETTE			hPalette;
 extern HPALETTE			hOldPalette;
@@ -254,6 +259,7 @@ extern DWORD   dwRomSize;
 extern LPBYTE  pbyRomDirtyPage;
 extern DWORD   dwRomDirtyPageSize;
 extern WORD    wRomCrc;
+extern BOOL    bRomCrcCorrection;
 extern LPBYTE  pbyPort2;
 extern BOOL    bPort2Writeable;
 extern BOOL    bPort2IsShared;
@@ -265,12 +271,12 @@ extern VOID    SetWindowLocation(HWND hWnd,INT nPosX,INT nPosY);
 extern DWORD   GetCutPathName(LPCTSTR szFileName,LPTSTR szBuffer,DWORD dwBufferLength,INT nCutLength);
 extern VOID    SetWindowPathTitle(LPCTSTR szFileName);
 extern BOOL    CheckForBeepPatch(VOID);
+extern BOOL    PatchNibble(DWORD dwAddress, BYTE byPatch);
 extern VOID    UpdatePatches(BOOL bPatch);
 extern BOOL    PatchRom(LPCTSTR szFilename);
 extern BOOL    CrcRom(WORD *pwChk);
 extern BOOL    MapRom(LPCTSTR szFilename);
 extern VOID    UnmapRom(VOID);
-extern BOOL    CrcPort2(WORD *pwCrc);
 extern BOOL    MapPort2(LPCTSTR szFilename);
 extern VOID    UnmapPort2(VOID);
 extern VOID    ResetDocument(VOID);
@@ -293,6 +299,9 @@ extern VOID    LoadIconDefault(VOID);
 extern HBITMAP LoadBitmapFile(LPCTSTR szFilename,BOOL bPalette);
 extern HRGN    CreateRgnFromBitmap(HBITMAP hBmp,COLORREF color,DWORD dwTol);
 
+// Romcrc.c
+extern VOID RebuildRomCrc(VOID);
+
 // Timer.c
 extern VOID  SetHP48Time(VOID);
 extern VOID  StartTimers(VOID);
diff --git a/app/src/main/cpp/core/apple.c b/app/src/main/cpp/core/apple.c
index 90da4d7..665f06e 100644
--- a/app/src/main/cpp/core/apple.c
+++ b/app/src/main/cpp/core/apple.c
@@ -16,8 +16,6 @@
 
 #define w Chipset
 
-#define _KB(s)	((s) * 1024 * 2)
-
 #pragma intrinsic(memset,memcpy)
 
 #include "Ops.h"
@@ -55,7 +53,7 @@ static CONST LPBYTE ppReg[] = { w.A, w.B, w.C, w.D };
 static QWORD DecodeReg64(LPBYTE R, BYTE byNF)
 {
 	QWORD qwVal = Npack64(R,16);			// generate 64bit number from register
-		
+
 	switch (byNF)							// field selector
 	{
 	case  0: return (qwVal >> (w.P*4)) & 0xf;			// P
@@ -324,7 +322,7 @@ _ASSERT(FALSE);								// not tested so far
 
 	// clear bank
 	EraseBlock(dwStart,dwStop-dwStart);
-		
+
 	w.carry = FALSE;						// no error
 	return;
 }
@@ -396,7 +394,7 @@ VOID o80BExt(LPBYTE I) // Saturnator extentions
 	case 0x0A: break; // KEYDN not implemented
 	case 0x0B: break; // no doslow implemented
 	case 0x10: // simulate off function
-		{					
+		{
 			BOOL bShutdn = TRUE;			// shut down
 
 			// only shut down when no timer wake up
diff --git a/app/src/main/cpp/core/disrpl.c b/app/src/main/cpp/core/disrpl.c
index 3120b53..494eae8 100644
--- a/app/src/main/cpp/core/disrpl.c
+++ b/app/src/main/cpp/core/disrpl.c
@@ -29,31 +29,36 @@ typedef struct
 
 static VOID PutSn(String *str, LPCTSTR szVal, DWORD dwLen)
 {
-	if (str != NULL)						// with output
+	if (str != NULL && dwLen > 0)			// with output and actual string length
 	{
-		if (str->dwSize == 0)				// no buffer allocated
+		// string buffer to small
+		if (str->dwPos + dwLen > str->dwSize)
 		{
-			str->dwSize = ALLOCSIZE;		// buffer size
-			VERIFY(str->szBuffer = (LPTSTR) malloc(str->dwSize * sizeof(TCHAR)));
-			str->dwPos = 0;
+			LPTSTR szNewBuffer;
+
+			DWORD dwMinSize;
+			dwMinSize = dwLen + str->dwSize - str->dwPos;
+			dwMinSize = (dwMinSize + ALLOCSIZE - 1) / ALLOCSIZE;
+			dwMinSize *= ALLOCSIZE;
+
+			str->dwSize += dwMinSize;		// new buffer size
+			VERIFY(szNewBuffer = (LPTSTR) realloc(str->szBuffer,str->dwSize * sizeof(TCHAR)));
+
+			if (szNewBuffer)				// new buffer allocated
+			{
+				str->szBuffer = szNewBuffer;
+			}
+			else							// allocation failed
+			{
+				str->dwSize = 0;			// size of buffer
+				free(str->szBuffer);		// buffer memory
+				str->szBuffer = NULL;
+				str->dwPos = 0;				// position inside buffer
+			}
 		}
 
-		_ASSERT(str->szBuffer != NULL);
-
-		if (dwLen > 0)						// actual string length
+		if (str->szBuffer)
 		{
-			// string buffer to small
-			if (str->dwPos + dwLen > str->dwSize)
-			{
-				DWORD dwMinSize;
-				dwMinSize = dwLen + str->dwSize - str->dwPos;
-				dwMinSize = (dwMinSize + ALLOCSIZE - 1) / ALLOCSIZE;
-				dwMinSize *= ALLOCSIZE;
-
-				str->dwSize += dwMinSize;	// new buffer size
-				VERIFY(str->szBuffer = (LPTSTR) realloc(str->szBuffer,str->dwSize * sizeof(TCHAR)));
-			}
-
 			CopyMemory(&str->szBuffer[str->dwPos],szVal,dwLen * sizeof(TCHAR));
 			str->dwPos += dwLen;
 		}
@@ -212,23 +217,24 @@ static BOOL BCDx(BYTE CONST *pbyNum,INT nMantLen,INT nExpLen,String *str)
 
 static BOOL BINx(DWORD *pdwAddr,INT nBinLen,String *str)
 {
-	LPBYTE pbyNumber;
-	INT    i;
-
-	VERIFY(pbyNumber = (LPBYTE) malloc(nBinLen));
-
-	for (i = 0; i < nBinLen; ++i)			// read data
-		pbyNumber[i] = RplReadNibble(pdwAddr);
-
-	// strip leading zeros
-	for (i = nBinLen - 1; pbyNumber[i] == 0 && i > 0; --i) { }
-
-	for (; i >= 0; --i)						// write rest of bin
+	LPBYTE pbyNumber = (LPBYTE) malloc(nBinLen);
+	if (pbyNumber != NULL)
 	{
-		PutC(str,cHex[pbyNumber[i]]);
-	}
+		INT i;
 
-	free(pbyNumber);
+		for (i = 0; i < nBinLen; ++i)		// read data
+			pbyNumber[i] = RplReadNibble(pdwAddr);
+
+		// strip leading zeros
+		for (i = nBinLen - 1; pbyNumber[i] == 0 && i > 0; --i) { }
+
+		for (; i >= 0; --i)					// write rest of bin
+		{
+			PutC(str,cHex[pbyNumber[i]]);
+		}
+
+		free(pbyNumber);
+	}
 	return FALSE;
 }
 
@@ -327,29 +333,31 @@ static BOOL DoIntStream(DWORD *pdwAddr,String *str,UINT *pnLevel)
 
 	dwLength -= 5;							// object length
 
-	VERIFY(pbyData = (LPBYTE) malloc(dwLength));
-
-	for (i = 0; i < dwLength; ++i)			// read data
-		pbyData[i] = RplReadNibble(pdwAddr);
-
-	if (dwLength <= 1)						// special implementation for zero
+	pbyData = (LPBYTE) malloc(dwLength);
+	if (pbyData != NULL)
 	{
-		_ASSERT(dwLength == 0 || (dwLength == 1 && pbyData[0] == 0));
-		PutC(str,_T('0'));
-	}
-	else
-	{
-		if (pbyData[--dwLength] == 9)		// negative number
-			PutC(str,_T('-'));
+		for (i = 0; i < dwLength; ++i)		// read data
+			pbyData[i] = RplReadNibble(pdwAddr);
 
-		while (dwLength > 0)				// write rest of zint
+		if (dwLength <= 1)					// special implementation for zero
 		{
-			// use only decimal part for translation
-			PutC(str,cHex[pbyData[--dwLength]]);
+			_ASSERT(dwLength == 0 || (dwLength == 1 && pbyData[0] == 0));
+			PutC(str,_T('0'));
 		}
-	}
+		else
+		{
+			if (pbyData[--dwLength] == 9)	// negative number
+				PutC(str,_T('-'));
 
-	free(pbyData);
+			while (dwLength > 0)			// write rest of zint
+			{
+				// use only decimal part for translation
+				PutC(str,cHex[pbyData[--dwLength]]);
+			}
+		}
+
+		free(pbyData);
+	}
 	return FALSE;
 	UNREFERENCED_PARAMETER(pnLevel);
 }
@@ -1291,9 +1299,9 @@ DWORD RplSkipObject(DWORD dwAddr)
 
 LPTSTR RplDecodeObject(DWORD dwAddr, DWORD *pdwNxtAddr)
 {
-	String	str = { 0 };
-	DWORD   dwNxtAddr;
-	UINT    nLevel = 0;						// don't nest DOCOL objects
+	String str = { 0, NULL, 0 };
+	DWORD  dwNxtAddr;
+	UINT   nLevel = 0;						// don't nest DOCOL objects
 
 	dwNxtAddr = dwAddr;						// init next address
 
@@ -1302,7 +1310,7 @@ LPTSTR RplDecodeObject(DWORD dwAddr, DWORD *pdwNxtAddr)
 
 	PutC(&str,0);							// set EOS
 
-	// release unnecessary allocated buffer memory
+	// release unnecessary allocated buffer memory (shrinking)
 	VERIFY(str.szBuffer = (LPTSTR) realloc(str.szBuffer,str.dwPos * sizeof(str.szBuffer[0])));
 
 	// return address of next object
@@ -1472,7 +1480,7 @@ static DWORD AssemblyOutput(DWORD dwAddr, DWORD dwEndAddr, DWORD dwLevel, String
 
 LPTSTR RplCreateObjView(DWORD dwStartAddr, DWORD dwEndAddr, BOOL bSingleObj)
 {
-	String	str = { 0 };
+	String  str = { 0, NULL, 0 };
 	LPCTSTR lpszName;
 	LPTSTR  lpszObject;
 	DWORD   dwLevel,dwAddr,dwNxtAddr;
@@ -1486,6 +1494,10 @@ LPTSTR RplCreateObjView(DWORD dwStartAddr, DWORD dwEndAddr, BOOL bSingleObj)
 	for (dwAddr = dwStartAddr;dwAddr < dwEndAddr; dwAddr = dwNxtAddr)
 	{
 		lpszObject = RplDecodeObject(dwAddr,&dwNxtAddr);
+		if (lpszObject == NULL)				// no memory
+		{
+			break;							// break decoding
+		}
 
 		if (dwLevel > 0 && lstrcmp(lpszObject,_T(";")) == 0)
 			--dwLevel;
@@ -1586,7 +1598,7 @@ LPTSTR RplCreateObjView(DWORD dwStartAddr, DWORD dwEndAddr, BOOL bSingleObj)
 
 	PutC(&str,0);							// set EOS
 
-	// release unnecessary allocated buffer memory
+	// release unnecessary allocated buffer memory (shrinking)
 	VERIFY(str.szBuffer = (LPTSTR) realloc(str.szBuffer,str.dwPos * sizeof(str.szBuffer[0])));
 	return str.szBuffer;
 }
diff --git a/app/src/main/cpp/core/emu48dll.c b/app/src/main/cpp/core/emu48dll.c
index 981b9f7..ac2edb4 100644
--- a/app/src/main/cpp/core/emu48dll.c
+++ b/app/src/main/cpp/core/emu48dll.c
@@ -78,15 +78,15 @@ BOOL WINAPI DllMain(HINSTANCE hinstDLL,DWORD fdwReason,LPVOID lpvReserved)
 //
 BOOL DLLCreateWnd(LPCTSTR lpszFilename, LPCTSTR lpszPort2Name)
 {
-	typedef DWORD (WINAPI *LPFN_STIP)(HANDLE hThread,DWORD dwIdealProcessor);
-
 	RECT rectWindow;
 	DWORD dwThreadId;
-	LPFN_STIP fnSetThreadIdealProcessor;
 	DWORD dwProcessor;
 
 	BOOL bFileExist = FALSE;				// state file don't exist
 
+	// module handle to kernel32
+	const HMODULE hmKernel32 = GetModuleHandle(_T("kernel32"));
+
 	hApp = GetModuleHandle(_T("EMU48.DLL"));
 	if (hApp == NULL) return TRUE;
 
@@ -113,6 +113,26 @@ BOOL DLLCreateWnd(LPCTSTR lpszFilename, LPCTSTR lpszPort2Name)
 	GetCurrentDirectory(ARRAYSIZEOF(szCurrentDirectory),szCurrentDirectory);
 	ReadSettings();
 
+	// disable TIMER_RESOLUTION throttling for Windows 11 and later
+	{
+		typedef const BOOL(WINAPI* LPFN_SPI)(HANDLE hProcess,INT ProcessInformationClass,LPVOID ProcessInformation,DWORD ProcessInformationSize);
+
+		// SetProcessInformation() is available since Windows 8, PROCESS_POWER_THROTTLING_IGNORE_TIMER_RESOLUTION since Windows 11
+		LPFN_SPI fnSetProcessInformation = (LPFN_SPI)GetProcAddress(hmKernel32, "SetProcessInformation");
+
+		if (fnSetProcessInformation != NULL)			// running on Windows 8 or later 
+		{
+			PROCESS_POWER_THROTTLING_STATE Ppts;
+
+			ZeroMemory(&Ppts,sizeof(Ppts));
+			Ppts.Version = PROCESS_POWER_THROTTLING_CURRENT_VERSION;
+			Ppts.ControlMask = PROCESS_POWER_THROTTLING_IGNORE_TIMER_RESOLUTION;
+
+			// don't check for success, success only on Windoes 11 and later
+			fnSetProcessInformation(GetCurrentProcess(),ProcessPowerThrottling,&Ppts,sizeof(Ppts));
+		}
+	}
+
 	// Create window
 	rectWindow.left   = 0;
 	rectWindow.top    = 0;
@@ -174,15 +194,29 @@ BOOL DLLCreateWnd(LPCTSTR lpszFilename, LPCTSTR lpszPort2Name)
 		return TRUE;
 	}
 
-	// SetThreadIdealProcessor() is available since Windows NT4.0
-	fnSetThreadIdealProcessor = (LPFN_STIP) GetProcAddress(GetModuleHandle(_T("kernel32")),
-														   "SetThreadIdealProcessor");
+	// get processor for Saturn CPU thread
+	{
+		// GetCurrentProcessorNumber() is available since Windows Vista
+		typedef const DWORD (WINAPI *LPFN_GCPN)(VOID);
+		LPFN_GCPN fnGetCurrentProcessorNumber = (LPFN_GCPN) GetProcAddress(hmKernel32,"GetCurrentProcessorNumber");
 
-	// bind Saturn CPU emulation thread to current ideal processor
-	dwProcessor = (fnSetThreadIdealProcessor != NULL)					// running on NT4.0 or later
-				? fnSetThreadIdealProcessor(hThread,MAXIMUM_PROCESSORS)	// get ideal processor no.
-				: 0;													// select 1st processor
+		if (fnGetCurrentProcessorNumber != NULL)								// running on Vista or later
+		{
+			dwProcessor = fnGetCurrentProcessorNumber();						// get current processor number
+		}
+		else
+		{
+			// SetThreadIdealProcessor() is available since Windows NT4.0
+			typedef const DWORD (WINAPI *LPFN_STIP)(HANDLE hThread,DWORD dwIdealProcessor);
+			LPFN_STIP fnSetThreadIdealProcessor = (LPFN_STIP) GetProcAddress(hmKernel32,"SetThreadIdealProcessor");
 
+			dwProcessor = (fnSetThreadIdealProcessor != NULL)					// running on NT4.0 or later
+						? fnSetThreadIdealProcessor(hThread,MAXIMUM_PROCESSORS)	// get ideal processor no.
+						: 0;													// select 1st processor
+		}
+	}
+
+	// bind Saturn CPU emulation thread to selected processor
 	// on multiprocessor machines for QueryPerformanceCounter()
 	VERIFY(SetThreadAffinityMask(hThread,(DWORD_PTR) (1 << dwProcessor)));
 	ResumeThread(hThread);					// start thread
diff --git a/app/src/main/cpp/core/external.c b/app/src/main/cpp/core/external.c
new file mode 100644
index 0000000..e548b54
--- /dev/null
+++ b/app/src/main/cpp/core/external.c
@@ -0,0 +1,101 @@
+/*
+ *   external.c
+ *
+ *   This file is part of Emu48
+ *
+ *   Copyright (C) 1995 Sebastien Carlier
+ *
+ */
+#include "pch.h"
+#include "Emu48.h"
+#include "ops.h"
+
+#define SAMPLES_PER_SEC		44100			// sound sampling rate
+
+//| 38G  | 39G  | 40G  | 48SX | 48GX | 49G  | Name
+//#F0E4F #80F0F #80F0F #706D2 #80850 #80F0F =SFLAG53_56
+
+// memory address for flags -53 to -56
+ // CdB for HP: add apples beep management
+#define SFLAG53_56	(  (cCurrentRomType=='6')								\
+					 ? 0xE0E4F												\
+					 : (  (cCurrentRomType=='A')							\
+						? 0xF0E4F											\
+						: (  (cCurrentRomType!='E' && cCurrentRomType!='X' && cCurrentRomType!='P' && cCurrentRomType!='2' && cCurrentRomType!='Q')	\
+						   ? (  (cCurrentRomType=='S')						\
+							  ? 0x706D2										\
+							  : 0x80850										\
+							 )												\
+						   : 0x80F0F										\
+						  )													\
+					   )													\
+					)
+
+VOID External(CHIPSET* w)					// Beep patch
+{
+	BYTE  fbeep;
+	DWORD freq,dur;
+
+	freq = Npack(w->D,5);					// frequency in Hz
+	dur = Npack(w->C,5);					// duration in ms
+	Nread(&fbeep,SFLAG53_56,1);				// fetch system flags -53 to -56
+
+	w->carry = TRUE;						// setting of no beep
+	if (!(fbeep & 0x8) && freq)				// bit -56 clear and frequency > 0 Hz
+	{
+		if (freq > 4400) freq = 4400;		// high limit of HP (SX)
+
+		SoundBeep(freq,dur);				// beeping
+
+		// estimate cpu cycles for beeping time (2MHz / 4MHz)
+		w->cycles += dur * ((cCurrentRomType=='S') ? 2000 : 4000);
+
+		// original routine return with...
+		w->P = 0;							// P=0
+		w->intk = TRUE;						// INTON
+		w->carry = FALSE;					// RTNCC
+	}
+	w->pc = rstkpop();
+	return;
+}
+
+VOID RCKBp(CHIPSET* w)						// ROM Check Beep patch
+{
+	DWORD dw2F,dwCpuFreq;
+	DWORD freq,dur;
+	BYTE f,d;
+
+	f = w->C[1];							// f = freq ctl
+	d = w->C[0];							// d = duration ctl
+	
+	if (cCurrentRomType == 'S')				// Clarke chip with 48S ROM
+	{	
+		// CPU strobe frequency @ RATE 14 = 1.97MHz
+		dwCpuFreq = ((14 + 1) * 524288) >> 2;
+
+		dw2F = f * 126 + 262;				// F=f*63+131
+	}
+	else									// York chip with 48G and later ROM
+	{
+		// CPU strobe frequency @ RATE 27 = 3.67MHz
+		// CPU strobe frequency @ RATE 29 = 3.93MHz
+		dwCpuFreq = ((27 + 1) * 524288) >> 2;
+
+		dw2F = f * 180 + 367;				// F=f*90+183.5
+	}
+
+	freq = dwCpuFreq / dw2F;
+	dur = (dw2F * (256 - 16 * d)) * 1000 / 2 / dwCpuFreq;
+
+	if (freq > 4400) freq = 4400;			// high limit of HP
+
+	SoundBeep(freq,dur);					// beeping
+
+	// estimate cpu cycles for beeping time (2MHz / 4MHz)
+	w->cycles += dur * ((cCurrentRomType=='S') ? 2000 : 4000);           
+
+	w->P = 0;								// P=0
+	w->carry = FALSE;						// RTNCC
+	w->pc = rstkpop();
+	return;
+}
diff --git a/app/src/main/cpp/core/files.c b/app/src/main/cpp/core/files.c
index 79d630b..d7c2e5b 100644
--- a/app/src/main/cpp/core/files.c
+++ b/app/src/main/cpp/core/files.c
@@ -42,6 +42,7 @@ DWORD  dwRomSize = 0;
 LPBYTE pbyRomDirtyPage = NULL;
 DWORD  dwRomDirtyPageSize = 0;
 WORD   wRomCrc = 0;							// fingerprint of patched ROM
+BOOL   bRomCrcCorrection = FALSE;			// ROM CRC correction disabled
 
 LPBYTE pbyPort2 = NULL;
 BOOL   bPort2Writeable = FALSE;
@@ -53,18 +54,21 @@ WORD   wPort2Crc = 0;						// fingerprint of port2
 BOOL   bBackup = FALSE;
 
 static HANDLE hRomFile = NULL;
-static HANDLE hRomMap = NULL;
 static HANDLE hPort2File = NULL;
 static HANDLE hPort2Map = NULL;
-
-// document signatures
-static BYTE pbySignatureA[16] = "Emu38 Document\xFE";
-static BYTE pbySignatureB[16] = "Emu39 Document\xFE";
-static BYTE pbySignatureE[16] = "Emu48 Document\xFE";
-static BYTE pbySignatureW[16] = "Win48 Document\xFE";
-static BYTE pbySignatureV[16] = "Emu49 Document\xFE";
 static HANDLE hCurrentFile = NULL;
 
+// valid document signatures
+static CONST LPBYTE bySignature[] =
+{
+	(CONST LPBYTE) "Emu48 Document\xFE",
+	(CONST LPBYTE) "Emu38 Document\xFE",
+	(CONST LPBYTE) "Emu39 Document\xFE",
+	(CONST LPBYTE) "Emu49 Document\xFE",
+	(CONST LPBYTE) "Win48 Document\xFE",
+	(CONST LPBYTE) "Win48 Document\xFF"
+};
+
 static CHIPSET BackupChipset;
 static LPBYTE  BackupPort0;
 static LPBYTE  BackupPort1;
@@ -102,11 +106,11 @@ VOID SetWindowLocation(HWND hWnd,INT nPosX,INT nPosY)
 
 DWORD GetCutPathName(LPCTSTR szFileName, LPTSTR szBuffer, DWORD dwBufferLength, INT nCutLength)
 {
-	TCHAR  cPath[_MAX_PATH];				// full filename
-	TCHAR  cDrive[_MAX_DRIVE];
-	TCHAR  cDir[_MAX_DIR];
-	TCHAR  cFname[_MAX_FNAME];
-	TCHAR  cExt[_MAX_EXT];
+	TCHAR cPath[_MAX_PATH];					// full filename
+	TCHAR cDrive[_MAX_DRIVE];
+	TCHAR cDir[_MAX_DIR];
+	TCHAR cFname[_MAX_FNAME];
+	TCHAR cExt[_MAX_EXT];
 
 	_ASSERT(nCutLength >= 0);				// 0 = only drive and name
 
@@ -209,7 +213,7 @@ BOOL CheckForBeepPatch(VOID)
 	} BEEPPATCH, *PBEEPPATCH;
 
 	// known beep patches
-	const BEEPPATCH s38[] =	{ { 0x017D0, { 0x8, 0x1, 0xB, 0x1 } } };
+	const BEEPPATCH s38[] = { { 0x017D0, { 0x8, 0x1, 0xB, 0x1 } } };
 	const BEEPPATCH s39[] = { { 0x017BC, { 0x8, 0x1, 0xB, 0x1 } } };
 	const BEEPPATCH s48[] = { { 0x017A6, { 0x8, 0x1, 0xB, 0x1 } } };
 	const BEEPPATCH s49[] = { { 0x4157A, { 0x8, 0x1, 0xB, 0x1 } },		// 1.18/1.19-5/1.19-6
@@ -289,7 +293,7 @@ typedef struct tnode
 
 static TREENODE *nodePatch = NULL;
 
-static BOOL PatchNibble(DWORD dwAddress, BYTE byPatch)
+BOOL PatchNibble(DWORD dwAddress, BYTE byPatch)
 {
 	PTREENODE p;
 
@@ -446,6 +450,7 @@ BOOL PatchRom(LPCTSTR szFilename)
 				{
 					// patch ROM and save original nibble
 					PatchNibble(dwAddress, Asc2Nib(lpBuf[nPos]));
+					bRomCrcCorrection = TRUE;
 				}
 				++dwAddress;
 			}
@@ -480,7 +485,7 @@ BOOL CrcRom(WORD *pwChk)					// calculate fingerprint of ROM
 	// use checksum, because it's faster
 	while (dwSize-- > 0)
 	{
-		DWORD dwData = *pdwData++;
+		CONST DWORD dwData = *pdwData++;
 		if ((dwData & 0xF0F0F0F0) != 0)		// data packed?
 			return FALSE;
 		dwChk += dwData;
@@ -501,6 +506,7 @@ BOOL MapRom(LPCTSTR szFilename)
 	{
 		return FALSE;
 	}
+	bRomCrcCorrection = FALSE;				// ROM CRC correction disabled
 	SetCurrentDirectory((*szRomDirectory == 0) ? szEmuDirectory : szRomDirectory);
 	if (bRomRW)								// ROM writeable
 	{
@@ -597,12 +603,13 @@ BOOL MapRom(LPCTSTR szFilename)
 
 	if (bRomPacked)							// packed ROM image
 	{
-		dwSize = dwRomSize;					// destination start address
-		while (dwFileSize > 0)				// unpack source
+		LPBYTE pbySrc = pbyRom+dwFileSize;	// source start address
+		LPBYTE pbyDest = pbyRom+dwRomSize;	// destination start address
+		while (pbySrc != pbyDest)			// unpack source
 		{
-			BYTE byValue = pbyRom[--dwFileSize];
-			pbyRom[--dwSize] = byValue >> 4;
-			pbyRom[--dwSize] = byValue & 0xF;
+			CONST BYTE byValue = *(--pbySrc);
+			*(--pbyDest) = byValue >> 4;
+			*(--pbyDest) = byValue & 0xF;
 		}
 	}
 	return TRUE;
@@ -638,19 +645,19 @@ VOID UnmapRom(VOID)
 
 				if (bRomPacked)				// repack data
 				{
-					LPBYTE pbySrc,pbyDest;
-					DWORD  j;
+					LPBYTE pbySrc,pbyDest,pbyEnd;
 
 					dwSize /= 2;			// adjust no. of bytes to write
 					dwFilePos /= 2;			// linear pos in packed file
 
 					// pack data in page
 					pbySrc = pbyDest = &pbyRom[dwLinPos];
-					for (j = 0; j < dwSize; j++)
+					pbyEnd = pbyDest + dwSize;
+					while (pbyDest < pbyEnd)
 					{
 						*pbyDest =  *pbySrc++;
 						*pbyDest |= *pbySrc++ << 4;
-						pbyDest++;
+						++pbyDest;
 					}
 				}
 
@@ -670,6 +677,7 @@ VOID UnmapRom(VOID)
 	pbyRom = NULL;
 	dwRomSize = 0;
 	wRomCrc = 0;
+	bRomCrcCorrection = FALSE;				// ROM CRC correction disabled
 	return;
 }
 
@@ -681,25 +689,24 @@ VOID UnmapRom(VOID)
 //#
 //################
 
-BOOL CrcPort2(WORD *pwCrc)					// calculate fingerprint of port2
+static BOOL CrcPort2(WORD *pwCrc)			// calculate fingerprint of port2
 {
-	DWORD dwCount;
-	DWORD dwFileSize;
-
 	*pwCrc = 0;
 
-	// port2 CRC isn't available
-	if (pbyPort2 == NULL) return TRUE;
-
-	dwFileSize = GetFileSize(hPort2File, &dwCount); // get real filesize
-	_ASSERT(dwCount == 0);					// isn't created by MapPort2()
-
-	for (dwCount = 0;dwCount < dwFileSize; ++dwCount)
+	if (pbyPort2 != NULL)					// port2 CRC available
 	{
-		if ((pbyPort2[dwCount] & 0xF0) != 0) // data packed?
-			return FALSE;
+		LPBYTE pbyMem;
 
-		*pwCrc = (*pwCrc >> 4) ^ (((*pwCrc ^ ((WORD) pbyPort2[dwCount])) & 0xf) * 0x1081);
+		// get real filesize
+		DWORD dwFileSize = GetFileSize(hPort2File, NULL);
+
+		for (pbyMem = pbyPort2; dwFileSize > 0; --dwFileSize)
+		{
+			if ((*pbyMem & 0xF0) != 0)		// data packed?
+				return FALSE;
+
+			*pwCrc = UpCRC(*pwCrc,*pbyMem++);
+		}
 	}
 	return TRUE;
 }
@@ -836,7 +843,7 @@ VOID ResetDocument(VOID)
 		hCurrentFile = NULL;
 	}
 	szCurrentKml[0] = 0;
-	szCurrentFilename[0]=0;
+	szCurrentFilename[0] = 0;
 	if (Port0) { free(Port0); Port0 = NULL; }
 	if (Port1) { free(Port1); Port1 = NULL; }
 	if (Port2) { free(Port2); Port2 = NULL; } else UnmapPort2();
@@ -919,17 +926,17 @@ BOOL NewDocument(VOID)
 	if (Chipset.Port0Size)
 	{
 		Port0 = (LPBYTE) calloc(Chipset.Port0Size*2048,sizeof(*Port0));
-		_ASSERT(Port0 != NULL);
+		if (Port0 == NULL) goto restore;
 	}
 	if (Chipset.Port1Size)
 	{
 		Port1 = (LPBYTE) calloc(Chipset.Port1Size*2048,sizeof(*Port1));
-		_ASSERT(Port1 != NULL);
+		if (Port1 == NULL) goto restore;
 	}
 	if (Chipset.Port2Size)
 	{
-		Port2 = (LPBYTE) calloc(Chipset.Port2Size*2048,sizeof(*Port1));
-		_ASSERT(Port2 != NULL);
+		Port2 = (LPBYTE) calloc(Chipset.Port2Size*2048,sizeof(*Port2));
+		if (Port2 == NULL) goto restore;
 	}
 	LoadBreakpointList(NULL);				// clear debugger breakpoint list
 	RomSwitch(0);							// boot ROM view of HP49G and map memory
@@ -958,10 +965,9 @@ BOOL OpenDocument(LPCTSTR szFilename)
 
 	HANDLE  hFile = INVALID_HANDLE_VALUE;
 	DWORD   lBytesRead,lSizeofChipset;
-	BYTE    pbyFileSignature[16];
-	LPBYTE  pbySig;
-	UINT    ctBytesCompared;
-	UINT    nLength;
+	BYTE    byFileSignature[16];
+	BOOL    bMatch;
+	UINT    i,nLength;
 
 	// Open file
 	if (lstrcmpi(szCurrentFilename,szFilename) == 0)
@@ -981,38 +987,19 @@ BOOL OpenDocument(LPCTSTR szFilename)
 	}
 
 	// Read and Compare signature
-	ReadFile(hFile, pbyFileSignature, 16, &lBytesRead, NULL);
-	switch (pbyFileSignature[0])
+	ReadFile(hFile, byFileSignature, sizeof(byFileSignature), &lBytesRead, NULL);
+	// go through all valid document signatures
+	for (bMatch = FALSE, i = 0; !bMatch && i < ARRAYSIZEOF(bySignature); ++i)
 	{
-	case 'E':
-		pbySig = (pbyFileSignature[3] == '3')
-			   ? ((pbyFileSignature[4] == '8') ? pbySignatureA : pbySignatureB)
-			   : ((pbyFileSignature[4] == '8') ? pbySignatureE : pbySignatureV);
-		for (ctBytesCompared=0; ctBytesCompared<14; ctBytesCompared++)
-		{
-			if (pbyFileSignature[ctBytesCompared]!=pbySig[ctBytesCompared])
-			{
-				AbortMessage(_T("This file is not a valid Emu48 document."));
-				goto restore;
-			}
-		}
-		break;
-	case 'W':
-		for (ctBytesCompared=0; ctBytesCompared<14; ctBytesCompared++)
-		{
-			if (pbyFileSignature[ctBytesCompared]!=pbySignatureW[ctBytesCompared])
-			{
-				AbortMessage(_T("This file is not a valid Win48 document."));
-				goto restore;
-			}
-		}
-		break;
-	default:
-		AbortMessage(_T("This file is not a valid document."));
+		bMatch = (memcmp(byFileSignature, bySignature[i], sizeof(byFileSignature)) == 0);
+	}
+	if (!bMatch)							// no valid document signature found
+	{
+		AbortMessage(_T("This file is not a valid Emu48 document."));
 		goto restore;
 	}
 
-	switch (pbyFileSignature[14])
+	switch (byFileSignature[14])
 	{
 	case 0xFE: // Win48 2.1 / Emu4x 0.99.x format
 		// read length of KML script name
@@ -1051,8 +1038,7 @@ BOOL OpenDocument(LPCTSTR szFilename)
 	case 0xFF: // Win48 2.05 format
 		break;
 	default:
-		AbortMessage(_T("This file is for an unknown version of Emu48."));
-		goto restore;
+		_ASSERT(FALSE);
 	}
 
 	// read chipset size inside file
@@ -1087,9 +1073,7 @@ BOOL OpenDocument(LPCTSTR szFilename)
 	{
 		if (szCurrentKml[0])				// KML file name
 		{
-			BOOL bOK;
-
-			bOK = InitKML(szCurrentKml,FALSE);
+			BOOL bOK = InitKML(szCurrentKml,FALSE);
 			bOK = bOK && (cCurrentRomType == Chipset.type);
 			if (bOK) break;
 
@@ -1228,9 +1212,10 @@ BOOL SaveDocument(VOID)
 
 	SetFilePointer(hCurrentFile,0,NULL,FILE_BEGIN);
 
-	if (!WriteFile(hCurrentFile, pbySignatureE, sizeof(pbySignatureE), &lBytesWritten, NULL))
+	// write default "Emu48 Document\xFE" signature
+	if (!WriteFile(hCurrentFile, bySignature[0], 16, &lBytesWritten, NULL))
 	{
-		AbortMessage(_T("Could not write into file !"));
+		AbortMessage(_T("Could not write into document file!"));
 		return FALSE;
 	}
 
@@ -1304,6 +1289,8 @@ BOOL SaveBackup(VOID)
 {
 	WINDOWPLACEMENT wndpl;
 
+	BOOL bSucc = TRUE;
+
 	if (!bDocumentAvail) return FALSE;
 
 	_ASSERT(nState != SM_RUN);				// emulation engine is running
@@ -1324,27 +1311,41 @@ BOOL SaveBackup(VOID)
 	if (Port0 && Chipset.Port0Size)
 	{
 		BackupPort0 = (LPBYTE) malloc(Chipset.Port0Size*2048);
-		CopyMemory(BackupPort0,Port0,Chipset.Port0Size*2048);
+		if (BackupPort0)
+		{
+			CopyMemory(BackupPort0,Port0,Chipset.Port0Size*2048);
+		}
+		bSucc = bSucc && (BackupPort0 != NULL);
 	}
 	if (Port1 && Chipset.Port1Size)
 	{
 		BackupPort1 = (LPBYTE) malloc(Chipset.Port1Size*2048);
-		CopyMemory(BackupPort1,Port1,Chipset.Port1Size*2048);
+		if (BackupPort1)
+		{
+			CopyMemory(BackupPort1,Port1,Chipset.Port1Size*2048);
+		}
+		bSucc = bSucc && (BackupPort1 != NULL);
 	}
 	if (Port2 && Chipset.Port2Size)			// internal port2
 	{
 		BackupPort2 = (LPBYTE) malloc(Chipset.Port2Size*2048);
-		CopyMemory(BackupPort2,Port2,Chipset.Port2Size*2048);
+		if (BackupPort2)
+		{
+			CopyMemory(BackupPort2,Port2,Chipset.Port2Size*2048);
+		}
+		bSucc = bSucc && (BackupPort2 != NULL);
 	}
 	CreateBackupBreakpointList();
-	bBackup = TRUE;
-	return TRUE;
+	bBackup = bSucc;
+	return bSucc;
 }
 
 BOOL RestoreBackup(VOID)
 {
 	BOOL bDbgOpen;
 
+	BOOL bSucc = TRUE;
+
 	if (!bBackup) return FALSE;
 
 	bDbgOpen = (nDbgState != DBG_OFF);		// debugger window open?
@@ -1371,17 +1372,29 @@ BOOL RestoreBackup(VOID)
 	if (BackupPort0 && Chipset.Port0Size)
 	{
 		Port0 = (LPBYTE) malloc(Chipset.Port0Size*2048);
-		CopyMemory(Port0,BackupPort0,Chipset.Port0Size*2048);
+		if (Port0)
+		{
+			CopyMemory(Port0,BackupPort0,Chipset.Port0Size*2048);
+		}
+		bSucc = bSucc && (Port0 != NULL);
 	}
 	if (BackupPort1 && Chipset.Port1Size)
 	{
 		Port1 = (LPBYTE) malloc(Chipset.Port1Size*2048);
-		CopyMemory(Port1,BackupPort1,Chipset.Port1Size*2048);
+		if (Port1)
+		{
+			CopyMemory(Port1,BackupPort1,Chipset.Port1Size*2048);
+		}
+		bSucc = bSucc && (Port1 != NULL);
 	}
 	if (BackupPort2 && Chipset.Port2Size)	// internal port2
 	{
 		Port2 = (LPBYTE) malloc(Chipset.Port2Size*2048);
-		CopyMemory(Port2,BackupPort2,Chipset.Port2Size*2048);
+		if (Port2)
+		{
+			CopyMemory(Port2,BackupPort2,Chipset.Port2Size*2048);
+		}
+		bSucc = bSucc && (Port2 != NULL);
 	}
 	// map port2
 	else
@@ -1397,8 +1410,12 @@ BOOL RestoreBackup(VOID)
 	SetWindowLocation(hWnd,Chipset.nPosX,Chipset.nPosY);
 	RestoreBackupBreakpointList();			// restore the debugger breakpoint list
 	if (bDbgOpen) OnToolDebug();			// reopen the debugger
-	bDocumentAvail = TRUE;					// document available
-	return TRUE;
+	if (!bSucc)								// restore not successful (memory allocation errors)
+	{
+		ResetDocument();					// cleanup remainders
+	}
+	bDocumentAvail = bSucc;					// document available
+	return bSucc;
 }
 
 BOOL ResetBackup(VOID)
@@ -2610,7 +2627,6 @@ HRGN CreateRgnFromBitmap(HBITMAP hBmp,COLORREF color,DWORD dwTol)
 	BOOL (*fnColorCmp)(DWORD dwColor1,DWORD dwColor2,DWORD dwTol);
 
 	DWORD dwRed,dwGreen,dwBlue;
-	HRGN hRgn;
 	LPRGNDATA pRgnData;
 	LPBITMAPINFO bi;
 	LPBYTE pbyBits;
@@ -2622,6 +2638,8 @@ HRGN CreateRgnFromBitmap(HBITMAP hBmp,COLORREF color,DWORD dwTol)
 	BOOL bFoundLeft;
 	BOOL bIsMask;
 
+	HRGN hRgn = NULL;						// no region defined
+
 	if (dwTol >= 1000)						// use CIE L*a*b compare
 	{
 		fnColorCmp = LabColorCmp;
@@ -2633,7 +2651,10 @@ HRGN CreateRgnFromBitmap(HBITMAP hBmp,COLORREF color,DWORD dwTol)
 	}
 
 	// allocate memory for extended image information incl. RGBQUAD color table
-	bi = (LPBITMAPINFO) calloc(1,sizeof(BITMAPINFOHEADER) + 256 * sizeof(RGBQUAD));
+	if ((bi = (LPBITMAPINFO) calloc(1,sizeof(BITMAPINFOHEADER) + 256 * sizeof(RGBQUAD))) == NULL)
+	{
+		return hRgn;						// no region
+	}
 	bi->bmiHeader.biSize = sizeof(bi->bmiHeader);
 	_ASSERT(bi->bmiHeader.biBitCount == 0); // for query without color table
 
@@ -2652,7 +2673,11 @@ HRGN CreateRgnFromBitmap(HBITMAP hBmp,COLORREF color,DWORD dwTol)
 	}
 
 	// allocate memory for image data (colors)
-	pbyBits = (LPBYTE) malloc(bi->bmiHeader.biSizeImage);
+	if ((pbyBits = (LPBYTE) malloc(bi->bmiHeader.biSizeImage)) == NULL)
+	{
+		free(bi);							// free bitmap info
+		return hRgn;						// no region
+	}
 
 	// fill bits buffer
 	GetDIBits(hWindowDC,hBmp,0,bi->bmiHeader.biHeight,pbyBits,bi,DIB_RGB_COLORS);
@@ -2697,18 +2722,20 @@ HRGN CreateRgnFromBitmap(HBITMAP hBmp,COLORREF color,DWORD dwTol)
 
 	// allocate memory for region data
 	pRgnData = (PRGNDATA) malloc(sizeof(RGNDATAHEADER) + dwRectsCount * sizeof(RECT));
+	if (pRgnData)
+	{
+		// fill it by default
+		ZeroMemory(&pRgnData->rdh,sizeof(pRgnData->rdh));
+		pRgnData->rdh.dwSize = sizeof(pRgnData->rdh);
+		pRgnData->rdh.iType = RDH_RECTANGLES;
+		SetRect(&pRgnData->rdh.rcBound,MAXLONG,MAXLONG,0,0);
+	}
 
-	// fill it by default
-	ZeroMemory(&pRgnData->rdh,sizeof(pRgnData->rdh));
-	pRgnData->rdh.dwSize = sizeof(pRgnData->rdh);
-	pRgnData->rdh.iType	 = RDH_RECTANGLES;
-	SetRect(&pRgnData->rdh.rcBound,MAXLONG,MAXLONG,0,0);
-
-	for (y = 0; y < bi->bmiHeader.biHeight; ++y)
+	for (y = 0; pRgnData && y < bi->bmiHeader.biHeight; ++y)
 	{
 		LPBYTE pbyLineStart = pbyColor;
 
-		for (x = 0; x < bi->bmiHeader.biWidth; ++x)
+		for (x = 0; pRgnData && x < bi->bmiHeader.biWidth; ++x)
 		{
 			// get color
 			switch (bi->bmiHeader.biBitCount)
@@ -2765,9 +2792,19 @@ HRGN CreateRgnFromBitmap(HBITMAP hBmp,COLORREF color,DWORD dwTol)
 					// if buffer full reallocate it with more room
 					if (pRgnData->rdh.nCount >= dwRectsCount)
 					{
-						dwRectsCount += ADD_RECTS_COUNT;
+						LPRGNDATA pNewRgnData;
 
-						pRgnData = (LPRGNDATA) realloc(pRgnData,sizeof(RGNDATAHEADER) + dwRectsCount * sizeof(RECT));
+						dwRectsCount += ADD_RECTS_COUNT;
+						pNewRgnData = (LPRGNDATA) realloc(pRgnData,sizeof(RGNDATAHEADER) + dwRectsCount * sizeof(RECT));
+						if (pNewRgnData)
+						{
+							pRgnData = pNewRgnData;
+						}
+						else
+						{
+							free(pRgnData);
+							pRgnData = NULL;
+						}
 					}
 
 					bFoundLeft = FALSE;
@@ -2782,10 +2819,11 @@ HRGN CreateRgnFromBitmap(HBITMAP hBmp,COLORREF color,DWORD dwTol)
 	free(pbyBits);
 	free(bi);
 
-	// create region
-	hRgn = ExtCreateRegion(NULL,sizeof(RGNDATAHEADER) + pRgnData->rdh.nCount * sizeof(RECT),pRgnData);
-
-	free(pRgnData);
+	if (pRgnData)							// has region data, create region
+	{
+		hRgn = ExtCreateRegion(NULL,sizeof(RGNDATAHEADER) + pRgnData->rdh.nCount * sizeof(RECT),pRgnData);
+		free(pRgnData);
+	}
 	return hRgn;
 	#undef ADD_RECTS_COUNT
 }
diff --git a/app/src/main/cpp/core/kml.c b/app/src/main/cpp/core/kml.c
index b8c3c5a..7e3ebbe 100644
--- a/app/src/main/cpp/core/kml.c
+++ b/app/src/main/cpp/core/kml.c
@@ -165,30 +165,23 @@ static VOID ClearLog()
 
 static VOID AddToLog(LPCTSTR szString)
 {
+	LPTSTR szLogTmp;
+
 	UINT nLength = lstrlen(szString) + 2;	// CR+LF
-	if (szLog == NULL)
+	if (szLog == NULL)						// no log
 	{
-		nLogLength = nLength + 1;			// \0
-		szLog = (LPTSTR) malloc(nLogLength*sizeof(szLog[0]));
-		if (szLog==NULL)
-		{
-			nLogLength = 0;
-			return;
-		}
-		lstrcpy(szLog,szString);
+		nLogLength = 1;						// room for \0
 	}
-	else
+
+	szLogTmp = (LPTSTR) realloc(szLog,(nLogLength+nLength)*sizeof(szLog[0]));
+	if (szLogTmp == NULL)
 	{
-		LPTSTR szLogTmp = (LPTSTR) realloc(szLog,(nLogLength+nLength)*sizeof(szLog[0]));
-		if (szLogTmp == NULL)
-		{
-			ClearLog();
-			return;
-		}
-		szLog = szLogTmp;
-		lstrcpy(&szLog[nLogLength-1],szString);
-		nLogLength += nLength;
+		ClearLog();
+		return;
 	}
+	szLog = szLogTmp;
+	lstrcpy(&szLog[nLogLength-1],szString);
+	nLogLength += nLength;
 	szLog[nLogLength-3] = _T('\r');
 	szLog[nLogLength-2] = _T('\n');
 	szLog[nLogLength-1] = 0;
@@ -274,11 +267,9 @@ static CHAR cKmlType;
 
 static VOID DestroyKmlList(VOID)
 {
-	KmlScript* pList;
-
 	while (pKmlList)
 	{
-		pList = pKmlList->pNext;
+		KmlScript* pList = pKmlList->pNext;
 		free(pKmlList->szFilename);
 		free(pKmlList->szTitle);
 		free(pKmlList);
@@ -304,36 +295,45 @@ static VOID CreateKmlList(VOID)
 		KmlScript* pScript;
 		KmlBlock*  pBlock;
 		LPCTSTR szTitle;
+		BOOL bInvalidPlatform;
 
 		pBlock = LoadKMLGlobal(pFindFileData.cFileName);
 		if (pBlock == NULL) continue;
 		// check for correct KML script platform
 		szTitle = GetStringParam(pBlock,TOK_GLOBAL,TOK_HARDWARE,0);
-		if (szTitle && lstrcmpi(_T(HARDWARE),szTitle) != 0)
-		{
-			FreeBlocks(pBlock);
-			continue;
-		}
+		bInvalidPlatform = (szTitle && lstrcmpi(_T(HARDWARE),szTitle) != 0);
 		// check for supported Model
 		szTitle = GetStringParam(pBlock,TOK_GLOBAL,TOK_MODEL,0);
-		// skip all scripts with invalid or different Model statement
-		if (   (szTitle == NULL)
+		// skip all scripts with invalid platform and invalid or different Model statement
+		if (   bInvalidPlatform
+			|| (szTitle == NULL)
 			|| (cKmlType && szTitle[0] != cKmlType)
 			|| !isModelValid(szTitle[0]))
 		{
 			FreeBlocks(pBlock);
 			continue;
 		}
-		VERIFY(pScript = (KmlScript*) malloc(sizeof(KmlScript)));
-		pScript->szFilename = DuplicateString(pFindFileData.cFileName);
-		szTitle = GetStringParam(pBlock,TOK_GLOBAL,TOK_TITLE,0);
-		if (szTitle == NULL) szTitle = pScript->szFilename;
-		pScript->szTitle = DuplicateString(szTitle);
+		pScript = (KmlScript*) malloc(sizeof(KmlScript));
+		if (pScript)						// script node allocated
+		{
+			pScript->szFilename = DuplicateString(pFindFileData.cFileName);
+			szTitle = GetStringParam(pBlock,TOK_GLOBAL,TOK_TITLE,0);
+			if (szTitle == NULL) szTitle = pScript->szFilename;
+			pScript->szTitle = DuplicateString(szTitle);
+			if (pScript->szFilename == NULL || pScript->szTitle == NULL)
+			{
+				free(pScript->szFilename);
+				free(pScript->szTitle);
+				free(pScript);
+				FreeBlocks(pBlock);
+				continue;
+			}
+			pScript->nId = nKmlFiles;
+			pScript->pNext = pKmlList;
+			pKmlList = pScript;
+			nKmlFiles++;
+		}
 		FreeBlocks(pBlock);
-		pScript->nId = nKmlFiles;
-		pScript->pNext = pKmlList;
-		pKmlList = pScript;
-		nKmlFiles++;
 	} while (FindNextFile(hFindFile,&pFindFileData));
 	FindClose(hFindFile);
 	return;
@@ -677,20 +677,29 @@ static DWORD ParseInteger(VOID)
 
 static LPTSTR ParseString(VOID)
 {
-	LPTSTR lpszString;
-	UINT   nLength;
-	UINT   nBlock;
+	LPTSTR lpszString = NULL;				// no mem allocated
+	UINT   nBlock = 0;
+	UINT   nLength = 0;
+
+	LPTSTR lpszAllocString;
 
 	szText++;								// skip leading '"'
-	nLength = 0;
-	nBlock = 256;
-	lpszString = (LPTSTR) malloc(nBlock * sizeof(lpszString[0]));
+
 	while (*szText != _T('"'))
 	{
-		if (nLength == nBlock - 1)			// ran out of buffer space
+		if (nLength >= nBlock)				// ran out of buffer space
 		{
 			nBlock += 256;
-			lpszString = (LPTSTR) realloc(lpszString,nBlock * sizeof(lpszString[0]));
+			lpszAllocString = (LPTSTR) realloc(lpszString,nBlock * sizeof(lpszString[0]));
+			if (lpszAllocString)
+			{
+				lpszString = lpszAllocString;
+			}
+			else
+			{
+				free(lpszString);			// cleanup allocation failture
+				return NULL;
+			}
 		}
 
 		if (*szText == _T('\\'))			// escape char
@@ -716,10 +725,17 @@ static LPTSTR ParseString(VOID)
 		lpszString[nLength++] = *szText++;	// save char
 	}
 	szText++;								// skip ending '"'
-	lpszString[nLength] = 0;				// set EOS
 
-	// release unnecessary allocated bytes
-	return (LPTSTR) realloc(lpszString,(nLength+1) * sizeof(lpszString[0]));
+	// release unnecessary allocated bytes or allocate byte for EOS
+	if ((lpszAllocString = (LPTSTR) realloc(lpszString,(nLength+1) * sizeof(lpszString[0]))))
+	{
+		lpszAllocString[nLength] = 0;		// set EOS
+	}
+	else
+	{
+		free(lpszString);					// cleanup allocation failture
+	}
+	return lpszAllocString;
 }
 
 static TokenId Lex(UINT nMode)
@@ -767,7 +783,9 @@ static KmlLine* ParseLine(TokenId eCommand)
 	}
 	if (pLexToken[i].nLen == 0) return NULL;
 
-	pLine = (KmlLine*) calloc(1,sizeof(KmlLine));
+	if ((pLine = (KmlLine*) calloc(1,sizeof(KmlLine))) == NULL)
+		return NULL;
+
 	pLine->eCommand = eCommand;
 
 	for (j = 0, nParams = pLexToken[i].nParams; TRUE; nParams >>= 3)
@@ -946,7 +964,10 @@ static KmlLine* ParseLines(BOOL bInclude)
 				if (pFirst == NULL)			// regular exit with empty block
 				{
 					// create an empty line
-					pLine = pFirst = (KmlLine*) calloc(1,sizeof(KmlLine));
+					if ((pFirst = (KmlLine*) calloc(1,sizeof(KmlLine))) == NULL)
+						goto abort;
+
+					pLine = pFirst;
 					pLine->eCommand = TOK_NONE;
 				}
 				if (pLine) pLine->pNext = NULL;
@@ -985,7 +1006,9 @@ static KmlBlock* ParseBlock(BOOL bInclude, TokenId eType)
 
 	nLinesIncludeLevel = 0;
 
-	VERIFY(pBlock = (KmlBlock *) calloc(1,sizeof(KmlBlock)));
+	if ((pBlock = (KmlBlock *) calloc(1,sizeof(KmlBlock))) == NULL)
+		return NULL;
+
 	pBlock->eType = eType;
 
 	for (i = 0; pLexToken[i].nLen; ++i)		// search for token
@@ -1829,7 +1852,7 @@ static VOID AdjustPixel(LPBYTE pbyPixel, BYTE byOffset)
 {
 	INT i = 3;								// BGR colors
 
-	while (--i >= 0)					
+	while (--i >= 0)
 	{
 		WORD wColor = (WORD) *pbyPixel + byOffset;
 		// jumpless saturation to 0xFF
@@ -2618,6 +2641,11 @@ BOOL InitKML(LPCTSTR szFilename, BOOL bNoLog)
 		AddToLog(_T("This KML Script doesn't specify the ROM to use, or the ROM could not be loaded."));
 		goto quit;
 	}
+	if (bRomCrcCorrection)					// ROM CRC correction enabled
+	{
+		AddToLog(_T("Rebuild the ROM CRC."));
+		RebuildRomCrc();					// rebuild the ROM CRC's
+	}
 	if (hMainDC == NULL)
 	{
 		AddToLog(_T("This KML Script doesn't specify the background bitmap, or bitmap could not be loaded."));
diff --git a/app/src/main/cpp/core/lodepng.c b/app/src/main/cpp/core/lodepng.c
index 9d82e29..2c807ef 100644
--- a/app/src/main/cpp/core/lodepng.c
+++ b/app/src/main/cpp/core/lodepng.c
@@ -1,7 +1,7 @@
 /*
-LodePNG version 20220717
+LodePNG version 20230410
 
-Copyright (c) 2005-2022 Lode Vandevenne
+Copyright (c) 2005-2023 Lode Vandevenne
 
 This software is provided 'as-is', without any express or implied
 warranty. In no event will the authors be held liable for any damages
@@ -44,7 +44,7 @@ Rename this file to lodepng.cpp to use it for C++, or to lodepng.c to use it for
 #pragma warning( disable : 4996 ) /*VS does not like fopen, but fopen_s is not standard C so unusable here*/
 #endif /*_MSC_VER */
 
-const char* LODEPNG_VERSION_STRING = "20220717";
+const char* LODEPNG_VERSION_STRING = "20230410";
 
 /*
 This source file is divided into the following large parts. The code sections
@@ -140,7 +140,6 @@ static size_t lodepng_strlen(const char* a) {
 
 #define LODEPNG_MAX(a, b) (((a) > (b)) ? (a) : (b))
 #define LODEPNG_MIN(a, b) (((a) < (b)) ? (a) : (b))
-#define LODEPNG_ABS(x) ((x) < 0 ? -(x) : (x))
 
 #if defined(LODEPNG_COMPILE_PNG) || defined(LODEPNG_COMPILE_DECODER)
 /* Safely check if adding two integers will overflow (no undefined
@@ -2374,54 +2373,328 @@ const LodePNGDecompressSettings lodepng_default_decompress_settings = {0, 0, 0,
 
 
 #ifdef LODEPNG_COMPILE_CRC
-/* CRC polynomial: 0xedb88320 */
-static unsigned lodepng_crc32_table[256] = {
-           0u, 1996959894u, 3993919788u, 2567524794u,  124634137u, 1886057615u, 3915621685u, 2657392035u,
-   249268274u, 2044508324u, 3772115230u, 2547177864u,  162941995u, 2125561021u, 3887607047u, 2428444049u,
-   498536548u, 1789927666u, 4089016648u, 2227061214u,  450548861u, 1843258603u, 4107580753u, 2211677639u,
-   325883990u, 1684777152u, 4251122042u, 2321926636u,  335633487u, 1661365465u, 4195302755u, 2366115317u,
-   997073096u, 1281953886u, 3579855332u, 2724688242u, 1006888145u, 1258607687u, 3524101629u, 2768942443u,
-   901097722u, 1119000684u, 3686517206u, 2898065728u,  853044451u, 1172266101u, 3705015759u, 2882616665u,
-   651767980u, 1373503546u, 3369554304u, 3218104598u,  565507253u, 1454621731u, 3485111705u, 3099436303u,
-   671266974u, 1594198024u, 3322730930u, 2970347812u,  795835527u, 1483230225u, 3244367275u, 3060149565u,
-  1994146192u,   31158534u, 2563907772u, 4023717930u, 1907459465u,  112637215u, 2680153253u, 3904427059u,
-  2013776290u,  251722036u, 2517215374u, 3775830040u, 2137656763u,  141376813u, 2439277719u, 3865271297u,
-  1802195444u,  476864866u, 2238001368u, 4066508878u, 1812370925u,  453092731u, 2181625025u, 4111451223u,
-  1706088902u,  314042704u, 2344532202u, 4240017532u, 1658658271u,  366619977u, 2362670323u, 4224994405u,
-  1303535960u,  984961486u, 2747007092u, 3569037538u, 1256170817u, 1037604311u, 2765210733u, 3554079995u,
-  1131014506u,  879679996u, 2909243462u, 3663771856u, 1141124467u,  855842277u, 2852801631u, 3708648649u,
-  1342533948u,  654459306u, 3188396048u, 3373015174u, 1466479909u,  544179635u, 3110523913u, 3462522015u,
-  1591671054u,  702138776u, 2966460450u, 3352799412u, 1504918807u,  783551873u, 3082640443u, 3233442989u,
-  3988292384u, 2596254646u,   62317068u, 1957810842u, 3939845945u, 2647816111u,   81470997u, 1943803523u,
-  3814918930u, 2489596804u,  225274430u, 2053790376u, 3826175755u, 2466906013u,  167816743u, 2097651377u,
-  4027552580u, 2265490386u,  503444072u, 1762050814u, 4150417245u, 2154129355u,  426522225u, 1852507879u,
-  4275313526u, 2312317920u,  282753626u, 1742555852u, 4189708143u, 2394877945u,  397917763u, 1622183637u,
-  3604390888u, 2714866558u,  953729732u, 1340076626u, 3518719985u, 2797360999u, 1068828381u, 1219638859u,
-  3624741850u, 2936675148u,  906185462u, 1090812512u, 3747672003u, 2825379669u,  829329135u, 1181335161u,
-  3412177804u, 3160834842u,  628085408u, 1382605366u, 3423369109u, 3138078467u,  570562233u, 1426400815u,
-  3317316542u, 2998733608u,  733239954u, 1555261956u, 3268935591u, 3050360625u,  752459403u, 1541320221u,
-  2607071920u, 3965973030u, 1969922972u,   40735498u, 2617837225u, 3943577151u, 1913087877u,   83908371u,
-  2512341634u, 3803740692u, 2075208622u,  213261112u, 2463272603u, 3855990285u, 2094854071u,  198958881u,
-  2262029012u, 4057260610u, 1759359992u,  534414190u, 2176718541u, 4139329115u, 1873836001u,  414664567u,
-  2282248934u, 4279200368u, 1711684554u,  285281116u, 2405801727u, 4167216745u, 1634467795u,  376229701u,
-  2685067896u, 3608007406u, 1308918612u,  956543938u, 2808555105u, 3495958263u, 1231636301u, 1047427035u,
-  2932959818u, 3654703836u, 1088359270u,  936918000u, 2847714899u, 3736837829u, 1202900863u,  817233897u,
-  3183342108u, 3401237130u, 1404277552u,  615818150u, 3134207493u, 3453421203u, 1423857449u,  601450431u,
-  3009837614u, 3294710456u, 1567103746u,  711928724u, 3020668471u, 3272380065u, 1510334235u,  755167117u
+
+static const unsigned lodepng_crc32_table0[256] = {
+  0x00000000u, 0x77073096u, 0xee0e612cu, 0x990951bau, 0x076dc419u, 0x706af48fu, 0xe963a535u, 0x9e6495a3u,
+  0x0edb8832u, 0x79dcb8a4u, 0xe0d5e91eu, 0x97d2d988u, 0x09b64c2bu, 0x7eb17cbdu, 0xe7b82d07u, 0x90bf1d91u,
+  0x1db71064u, 0x6ab020f2u, 0xf3b97148u, 0x84be41deu, 0x1adad47du, 0x6ddde4ebu, 0xf4d4b551u, 0x83d385c7u,
+  0x136c9856u, 0x646ba8c0u, 0xfd62f97au, 0x8a65c9ecu, 0x14015c4fu, 0x63066cd9u, 0xfa0f3d63u, 0x8d080df5u,
+  0x3b6e20c8u, 0x4c69105eu, 0xd56041e4u, 0xa2677172u, 0x3c03e4d1u, 0x4b04d447u, 0xd20d85fdu, 0xa50ab56bu,
+  0x35b5a8fau, 0x42b2986cu, 0xdbbbc9d6u, 0xacbcf940u, 0x32d86ce3u, 0x45df5c75u, 0xdcd60dcfu, 0xabd13d59u,
+  0x26d930acu, 0x51de003au, 0xc8d75180u, 0xbfd06116u, 0x21b4f4b5u, 0x56b3c423u, 0xcfba9599u, 0xb8bda50fu,
+  0x2802b89eu, 0x5f058808u, 0xc60cd9b2u, 0xb10be924u, 0x2f6f7c87u, 0x58684c11u, 0xc1611dabu, 0xb6662d3du,
+  0x76dc4190u, 0x01db7106u, 0x98d220bcu, 0xefd5102au, 0x71b18589u, 0x06b6b51fu, 0x9fbfe4a5u, 0xe8b8d433u,
+  0x7807c9a2u, 0x0f00f934u, 0x9609a88eu, 0xe10e9818u, 0x7f6a0dbbu, 0x086d3d2du, 0x91646c97u, 0xe6635c01u,
+  0x6b6b51f4u, 0x1c6c6162u, 0x856530d8u, 0xf262004eu, 0x6c0695edu, 0x1b01a57bu, 0x8208f4c1u, 0xf50fc457u,
+  0x65b0d9c6u, 0x12b7e950u, 0x8bbeb8eau, 0xfcb9887cu, 0x62dd1ddfu, 0x15da2d49u, 0x8cd37cf3u, 0xfbd44c65u,
+  0x4db26158u, 0x3ab551ceu, 0xa3bc0074u, 0xd4bb30e2u, 0x4adfa541u, 0x3dd895d7u, 0xa4d1c46du, 0xd3d6f4fbu,
+  0x4369e96au, 0x346ed9fcu, 0xad678846u, 0xda60b8d0u, 0x44042d73u, 0x33031de5u, 0xaa0a4c5fu, 0xdd0d7cc9u,
+  0x5005713cu, 0x270241aau, 0xbe0b1010u, 0xc90c2086u, 0x5768b525u, 0x206f85b3u, 0xb966d409u, 0xce61e49fu,
+  0x5edef90eu, 0x29d9c998u, 0xb0d09822u, 0xc7d7a8b4u, 0x59b33d17u, 0x2eb40d81u, 0xb7bd5c3bu, 0xc0ba6cadu,
+  0xedb88320u, 0x9abfb3b6u, 0x03b6e20cu, 0x74b1d29au, 0xead54739u, 0x9dd277afu, 0x04db2615u, 0x73dc1683u,
+  0xe3630b12u, 0x94643b84u, 0x0d6d6a3eu, 0x7a6a5aa8u, 0xe40ecf0bu, 0x9309ff9du, 0x0a00ae27u, 0x7d079eb1u,
+  0xf00f9344u, 0x8708a3d2u, 0x1e01f268u, 0x6906c2feu, 0xf762575du, 0x806567cbu, 0x196c3671u, 0x6e6b06e7u,
+  0xfed41b76u, 0x89d32be0u, 0x10da7a5au, 0x67dd4accu, 0xf9b9df6fu, 0x8ebeeff9u, 0x17b7be43u, 0x60b08ed5u,
+  0xd6d6a3e8u, 0xa1d1937eu, 0x38d8c2c4u, 0x4fdff252u, 0xd1bb67f1u, 0xa6bc5767u, 0x3fb506ddu, 0x48b2364bu,
+  0xd80d2bdau, 0xaf0a1b4cu, 0x36034af6u, 0x41047a60u, 0xdf60efc3u, 0xa867df55u, 0x316e8eefu, 0x4669be79u,
+  0xcb61b38cu, 0xbc66831au, 0x256fd2a0u, 0x5268e236u, 0xcc0c7795u, 0xbb0b4703u, 0x220216b9u, 0x5505262fu,
+  0xc5ba3bbeu, 0xb2bd0b28u, 0x2bb45a92u, 0x5cb36a04u, 0xc2d7ffa7u, 0xb5d0cf31u, 0x2cd99e8bu, 0x5bdeae1du,
+  0x9b64c2b0u, 0xec63f226u, 0x756aa39cu, 0x026d930au, 0x9c0906a9u, 0xeb0e363fu, 0x72076785u, 0x05005713u,
+  0x95bf4a82u, 0xe2b87a14u, 0x7bb12baeu, 0x0cb61b38u, 0x92d28e9bu, 0xe5d5be0du, 0x7cdcefb7u, 0x0bdbdf21u,
+  0x86d3d2d4u, 0xf1d4e242u, 0x68ddb3f8u, 0x1fda836eu, 0x81be16cdu, 0xf6b9265bu, 0x6fb077e1u, 0x18b74777u,
+  0x88085ae6u, 0xff0f6a70u, 0x66063bcau, 0x11010b5cu, 0x8f659effu, 0xf862ae69u, 0x616bffd3u, 0x166ccf45u,
+  0xa00ae278u, 0xd70dd2eeu, 0x4e048354u, 0x3903b3c2u, 0xa7672661u, 0xd06016f7u, 0x4969474du, 0x3e6e77dbu,
+  0xaed16a4au, 0xd9d65adcu, 0x40df0b66u, 0x37d83bf0u, 0xa9bcae53u, 0xdebb9ec5u, 0x47b2cf7fu, 0x30b5ffe9u,
+  0xbdbdf21cu, 0xcabac28au, 0x53b39330u, 0x24b4a3a6u, 0xbad03605u, 0xcdd70693u, 0x54de5729u, 0x23d967bfu,
+  0xb3667a2eu, 0xc4614ab8u, 0x5d681b02u, 0x2a6f2b94u, 0xb40bbe37u, 0xc30c8ea1u, 0x5a05df1bu, 0x2d02ef8du
 };
 
-/*Return the CRC of the bytes buf[0..len-1].*/
+static const unsigned lodepng_crc32_table1[256] = {
+  0x00000000u, 0x191b3141u, 0x32366282u, 0x2b2d53c3u, 0x646cc504u, 0x7d77f445u, 0x565aa786u, 0x4f4196c7u,
+  0xc8d98a08u, 0xd1c2bb49u, 0xfaefe88au, 0xe3f4d9cbu, 0xacb54f0cu, 0xb5ae7e4du, 0x9e832d8eu, 0x87981ccfu,
+  0x4ac21251u, 0x53d92310u, 0x78f470d3u, 0x61ef4192u, 0x2eaed755u, 0x37b5e614u, 0x1c98b5d7u, 0x05838496u,
+  0x821b9859u, 0x9b00a918u, 0xb02dfadbu, 0xa936cb9au, 0xe6775d5du, 0xff6c6c1cu, 0xd4413fdfu, 0xcd5a0e9eu,
+  0x958424a2u, 0x8c9f15e3u, 0xa7b24620u, 0xbea97761u, 0xf1e8e1a6u, 0xe8f3d0e7u, 0xc3de8324u, 0xdac5b265u,
+  0x5d5daeaau, 0x44469febu, 0x6f6bcc28u, 0x7670fd69u, 0x39316baeu, 0x202a5aefu, 0x0b07092cu, 0x121c386du,
+  0xdf4636f3u, 0xc65d07b2u, 0xed705471u, 0xf46b6530u, 0xbb2af3f7u, 0xa231c2b6u, 0x891c9175u, 0x9007a034u,
+  0x179fbcfbu, 0x0e848dbau, 0x25a9de79u, 0x3cb2ef38u, 0x73f379ffu, 0x6ae848beu, 0x41c51b7du, 0x58de2a3cu,
+  0xf0794f05u, 0xe9627e44u, 0xc24f2d87u, 0xdb541cc6u, 0x94158a01u, 0x8d0ebb40u, 0xa623e883u, 0xbf38d9c2u,
+  0x38a0c50du, 0x21bbf44cu, 0x0a96a78fu, 0x138d96ceu, 0x5ccc0009u, 0x45d73148u, 0x6efa628bu, 0x77e153cau,
+  0xbabb5d54u, 0xa3a06c15u, 0x888d3fd6u, 0x91960e97u, 0xded79850u, 0xc7cca911u, 0xece1fad2u, 0xf5facb93u,
+  0x7262d75cu, 0x6b79e61du, 0x4054b5deu, 0x594f849fu, 0x160e1258u, 0x0f152319u, 0x243870dau, 0x3d23419bu,
+  0x65fd6ba7u, 0x7ce65ae6u, 0x57cb0925u, 0x4ed03864u, 0x0191aea3u, 0x188a9fe2u, 0x33a7cc21u, 0x2abcfd60u,
+  0xad24e1afu, 0xb43fd0eeu, 0x9f12832du, 0x8609b26cu, 0xc94824abu, 0xd05315eau, 0xfb7e4629u, 0xe2657768u,
+  0x2f3f79f6u, 0x362448b7u, 0x1d091b74u, 0x04122a35u, 0x4b53bcf2u, 0x52488db3u, 0x7965de70u, 0x607eef31u,
+  0xe7e6f3feu, 0xfefdc2bfu, 0xd5d0917cu, 0xcccba03du, 0x838a36fau, 0x9a9107bbu, 0xb1bc5478u, 0xa8a76539u,
+  0x3b83984bu, 0x2298a90au, 0x09b5fac9u, 0x10aecb88u, 0x5fef5d4fu, 0x46f46c0eu, 0x6dd93fcdu, 0x74c20e8cu,
+  0xf35a1243u, 0xea412302u, 0xc16c70c1u, 0xd8774180u, 0x9736d747u, 0x8e2de606u, 0xa500b5c5u, 0xbc1b8484u,
+  0x71418a1au, 0x685abb5bu, 0x4377e898u, 0x5a6cd9d9u, 0x152d4f1eu, 0x0c367e5fu, 0x271b2d9cu, 0x3e001cddu,
+  0xb9980012u, 0xa0833153u, 0x8bae6290u, 0x92b553d1u, 0xddf4c516u, 0xc4eff457u, 0xefc2a794u, 0xf6d996d5u,
+  0xae07bce9u, 0xb71c8da8u, 0x9c31de6bu, 0x852aef2au, 0xca6b79edu, 0xd37048acu, 0xf85d1b6fu, 0xe1462a2eu,
+  0x66de36e1u, 0x7fc507a0u, 0x54e85463u, 0x4df36522u, 0x02b2f3e5u, 0x1ba9c2a4u, 0x30849167u, 0x299fa026u,
+  0xe4c5aeb8u, 0xfdde9ff9u, 0xd6f3cc3au, 0xcfe8fd7bu, 0x80a96bbcu, 0x99b25afdu, 0xb29f093eu, 0xab84387fu,
+  0x2c1c24b0u, 0x350715f1u, 0x1e2a4632u, 0x07317773u, 0x4870e1b4u, 0x516bd0f5u, 0x7a468336u, 0x635db277u,
+  0xcbfad74eu, 0xd2e1e60fu, 0xf9ccb5ccu, 0xe0d7848du, 0xaf96124au, 0xb68d230bu, 0x9da070c8u, 0x84bb4189u,
+  0x03235d46u, 0x1a386c07u, 0x31153fc4u, 0x280e0e85u, 0x674f9842u, 0x7e54a903u, 0x5579fac0u, 0x4c62cb81u,
+  0x8138c51fu, 0x9823f45eu, 0xb30ea79du, 0xaa1596dcu, 0xe554001bu, 0xfc4f315au, 0xd7626299u, 0xce7953d8u,
+  0x49e14f17u, 0x50fa7e56u, 0x7bd72d95u, 0x62cc1cd4u, 0x2d8d8a13u, 0x3496bb52u, 0x1fbbe891u, 0x06a0d9d0u,
+  0x5e7ef3ecu, 0x4765c2adu, 0x6c48916eu, 0x7553a02fu, 0x3a1236e8u, 0x230907a9u, 0x0824546au, 0x113f652bu,
+  0x96a779e4u, 0x8fbc48a5u, 0xa4911b66u, 0xbd8a2a27u, 0xf2cbbce0u, 0xebd08da1u, 0xc0fdde62u, 0xd9e6ef23u,
+  0x14bce1bdu, 0x0da7d0fcu, 0x268a833fu, 0x3f91b27eu, 0x70d024b9u, 0x69cb15f8u, 0x42e6463bu, 0x5bfd777au,
+  0xdc656bb5u, 0xc57e5af4u, 0xee530937u, 0xf7483876u, 0xb809aeb1u, 0xa1129ff0u, 0x8a3fcc33u, 0x9324fd72u
+};
+
+static const unsigned lodepng_crc32_table2[256] = {
+  0x00000000u, 0x01c26a37u, 0x0384d46eu, 0x0246be59u, 0x0709a8dcu, 0x06cbc2ebu, 0x048d7cb2u, 0x054f1685u,
+  0x0e1351b8u, 0x0fd13b8fu, 0x0d9785d6u, 0x0c55efe1u, 0x091af964u, 0x08d89353u, 0x0a9e2d0au, 0x0b5c473du,
+  0x1c26a370u, 0x1de4c947u, 0x1fa2771eu, 0x1e601d29u, 0x1b2f0bacu, 0x1aed619bu, 0x18abdfc2u, 0x1969b5f5u,
+  0x1235f2c8u, 0x13f798ffu, 0x11b126a6u, 0x10734c91u, 0x153c5a14u, 0x14fe3023u, 0x16b88e7au, 0x177ae44du,
+  0x384d46e0u, 0x398f2cd7u, 0x3bc9928eu, 0x3a0bf8b9u, 0x3f44ee3cu, 0x3e86840bu, 0x3cc03a52u, 0x3d025065u,
+  0x365e1758u, 0x379c7d6fu, 0x35dac336u, 0x3418a901u, 0x3157bf84u, 0x3095d5b3u, 0x32d36beau, 0x331101ddu,
+  0x246be590u, 0x25a98fa7u, 0x27ef31feu, 0x262d5bc9u, 0x23624d4cu, 0x22a0277bu, 0x20e69922u, 0x2124f315u,
+  0x2a78b428u, 0x2bbade1fu, 0x29fc6046u, 0x283e0a71u, 0x2d711cf4u, 0x2cb376c3u, 0x2ef5c89au, 0x2f37a2adu,
+  0x709a8dc0u, 0x7158e7f7u, 0x731e59aeu, 0x72dc3399u, 0x7793251cu, 0x76514f2bu, 0x7417f172u, 0x75d59b45u,
+  0x7e89dc78u, 0x7f4bb64fu, 0x7d0d0816u, 0x7ccf6221u, 0x798074a4u, 0x78421e93u, 0x7a04a0cau, 0x7bc6cafdu,
+  0x6cbc2eb0u, 0x6d7e4487u, 0x6f38fadeu, 0x6efa90e9u, 0x6bb5866cu, 0x6a77ec5bu, 0x68315202u, 0x69f33835u,
+  0x62af7f08u, 0x636d153fu, 0x612bab66u, 0x60e9c151u, 0x65a6d7d4u, 0x6464bde3u, 0x662203bau, 0x67e0698du,
+  0x48d7cb20u, 0x4915a117u, 0x4b531f4eu, 0x4a917579u, 0x4fde63fcu, 0x4e1c09cbu, 0x4c5ab792u, 0x4d98dda5u,
+  0x46c49a98u, 0x4706f0afu, 0x45404ef6u, 0x448224c1u, 0x41cd3244u, 0x400f5873u, 0x4249e62au, 0x438b8c1du,
+  0x54f16850u, 0x55330267u, 0x5775bc3eu, 0x56b7d609u, 0x53f8c08cu, 0x523aaabbu, 0x507c14e2u, 0x51be7ed5u,
+  0x5ae239e8u, 0x5b2053dfu, 0x5966ed86u, 0x58a487b1u, 0x5deb9134u, 0x5c29fb03u, 0x5e6f455au, 0x5fad2f6du,
+  0xe1351b80u, 0xe0f771b7u, 0xe2b1cfeeu, 0xe373a5d9u, 0xe63cb35cu, 0xe7fed96bu, 0xe5b86732u, 0xe47a0d05u,
+  0xef264a38u, 0xeee4200fu, 0xeca29e56u, 0xed60f461u, 0xe82fe2e4u, 0xe9ed88d3u, 0xebab368au, 0xea695cbdu,
+  0xfd13b8f0u, 0xfcd1d2c7u, 0xfe976c9eu, 0xff5506a9u, 0xfa1a102cu, 0xfbd87a1bu, 0xf99ec442u, 0xf85cae75u,
+  0xf300e948u, 0xf2c2837fu, 0xf0843d26u, 0xf1465711u, 0xf4094194u, 0xf5cb2ba3u, 0xf78d95fau, 0xf64fffcdu,
+  0xd9785d60u, 0xd8ba3757u, 0xdafc890eu, 0xdb3ee339u, 0xde71f5bcu, 0xdfb39f8bu, 0xddf521d2u, 0xdc374be5u,
+  0xd76b0cd8u, 0xd6a966efu, 0xd4efd8b6u, 0xd52db281u, 0xd062a404u, 0xd1a0ce33u, 0xd3e6706au, 0xd2241a5du,
+  0xc55efe10u, 0xc49c9427u, 0xc6da2a7eu, 0xc7184049u, 0xc25756ccu, 0xc3953cfbu, 0xc1d382a2u, 0xc011e895u,
+  0xcb4dafa8u, 0xca8fc59fu, 0xc8c97bc6u, 0xc90b11f1u, 0xcc440774u, 0xcd866d43u, 0xcfc0d31au, 0xce02b92du,
+  0x91af9640u, 0x906dfc77u, 0x922b422eu, 0x93e92819u, 0x96a63e9cu, 0x976454abu, 0x9522eaf2u, 0x94e080c5u,
+  0x9fbcc7f8u, 0x9e7eadcfu, 0x9c381396u, 0x9dfa79a1u, 0x98b56f24u, 0x99770513u, 0x9b31bb4au, 0x9af3d17du,
+  0x8d893530u, 0x8c4b5f07u, 0x8e0de15eu, 0x8fcf8b69u, 0x8a809decu, 0x8b42f7dbu, 0x89044982u, 0x88c623b5u,
+  0x839a6488u, 0x82580ebfu, 0x801eb0e6u, 0x81dcdad1u, 0x8493cc54u, 0x8551a663u, 0x8717183au, 0x86d5720du,
+  0xa9e2d0a0u, 0xa820ba97u, 0xaa6604ceu, 0xaba46ef9u, 0xaeeb787cu, 0xaf29124bu, 0xad6fac12u, 0xacadc625u,
+  0xa7f18118u, 0xa633eb2fu, 0xa4755576u, 0xa5b73f41u, 0xa0f829c4u, 0xa13a43f3u, 0xa37cfdaau, 0xa2be979du,
+  0xb5c473d0u, 0xb40619e7u, 0xb640a7beu, 0xb782cd89u, 0xb2cddb0cu, 0xb30fb13bu, 0xb1490f62u, 0xb08b6555u,
+  0xbbd72268u, 0xba15485fu, 0xb853f606u, 0xb9919c31u, 0xbcde8ab4u, 0xbd1ce083u, 0xbf5a5edau, 0xbe9834edu
+};
+
+static const unsigned lodepng_crc32_table3[256] = {
+  0x00000000u, 0xb8bc6765u, 0xaa09c88bu, 0x12b5afeeu, 0x8f629757u, 0x37def032u, 0x256b5fdcu, 0x9dd738b9u,
+  0xc5b428efu, 0x7d084f8au, 0x6fbde064u, 0xd7018701u, 0x4ad6bfb8u, 0xf26ad8ddu, 0xe0df7733u, 0x58631056u,
+  0x5019579fu, 0xe8a530fau, 0xfa109f14u, 0x42acf871u, 0xdf7bc0c8u, 0x67c7a7adu, 0x75720843u, 0xcdce6f26u,
+  0x95ad7f70u, 0x2d111815u, 0x3fa4b7fbu, 0x8718d09eu, 0x1acfe827u, 0xa2738f42u, 0xb0c620acu, 0x087a47c9u,
+  0xa032af3eu, 0x188ec85bu, 0x0a3b67b5u, 0xb28700d0u, 0x2f503869u, 0x97ec5f0cu, 0x8559f0e2u, 0x3de59787u,
+  0x658687d1u, 0xdd3ae0b4u, 0xcf8f4f5au, 0x7733283fu, 0xeae41086u, 0x525877e3u, 0x40edd80du, 0xf851bf68u,
+  0xf02bf8a1u, 0x48979fc4u, 0x5a22302au, 0xe29e574fu, 0x7f496ff6u, 0xc7f50893u, 0xd540a77du, 0x6dfcc018u,
+  0x359fd04eu, 0x8d23b72bu, 0x9f9618c5u, 0x272a7fa0u, 0xbafd4719u, 0x0241207cu, 0x10f48f92u, 0xa848e8f7u,
+  0x9b14583du, 0x23a83f58u, 0x311d90b6u, 0x89a1f7d3u, 0x1476cf6au, 0xaccaa80fu, 0xbe7f07e1u, 0x06c36084u,
+  0x5ea070d2u, 0xe61c17b7u, 0xf4a9b859u, 0x4c15df3cu, 0xd1c2e785u, 0x697e80e0u, 0x7bcb2f0eu, 0xc377486bu,
+  0xcb0d0fa2u, 0x73b168c7u, 0x6104c729u, 0xd9b8a04cu, 0x446f98f5u, 0xfcd3ff90u, 0xee66507eu, 0x56da371bu,
+  0x0eb9274du, 0xb6054028u, 0xa4b0efc6u, 0x1c0c88a3u, 0x81dbb01au, 0x3967d77fu, 0x2bd27891u, 0x936e1ff4u,
+  0x3b26f703u, 0x839a9066u, 0x912f3f88u, 0x299358edu, 0xb4446054u, 0x0cf80731u, 0x1e4da8dfu, 0xa6f1cfbau,
+  0xfe92dfecu, 0x462eb889u, 0x549b1767u, 0xec277002u, 0x71f048bbu, 0xc94c2fdeu, 0xdbf98030u, 0x6345e755u,
+  0x6b3fa09cu, 0xd383c7f9u, 0xc1366817u, 0x798a0f72u, 0xe45d37cbu, 0x5ce150aeu, 0x4e54ff40u, 0xf6e89825u,
+  0xae8b8873u, 0x1637ef16u, 0x048240f8u, 0xbc3e279du, 0x21e91f24u, 0x99557841u, 0x8be0d7afu, 0x335cb0cau,
+  0xed59b63bu, 0x55e5d15eu, 0x47507eb0u, 0xffec19d5u, 0x623b216cu, 0xda874609u, 0xc832e9e7u, 0x708e8e82u,
+  0x28ed9ed4u, 0x9051f9b1u, 0x82e4565fu, 0x3a58313au, 0xa78f0983u, 0x1f336ee6u, 0x0d86c108u, 0xb53aa66du,
+  0xbd40e1a4u, 0x05fc86c1u, 0x1749292fu, 0xaff54e4au, 0x322276f3u, 0x8a9e1196u, 0x982bbe78u, 0x2097d91du,
+  0x78f4c94bu, 0xc048ae2eu, 0xd2fd01c0u, 0x6a4166a5u, 0xf7965e1cu, 0x4f2a3979u, 0x5d9f9697u, 0xe523f1f2u,
+  0x4d6b1905u, 0xf5d77e60u, 0xe762d18eu, 0x5fdeb6ebu, 0xc2098e52u, 0x7ab5e937u, 0x680046d9u, 0xd0bc21bcu,
+  0x88df31eau, 0x3063568fu, 0x22d6f961u, 0x9a6a9e04u, 0x07bda6bdu, 0xbf01c1d8u, 0xadb46e36u, 0x15080953u,
+  0x1d724e9au, 0xa5ce29ffu, 0xb77b8611u, 0x0fc7e174u, 0x9210d9cdu, 0x2aacbea8u, 0x38191146u, 0x80a57623u,
+  0xd8c66675u, 0x607a0110u, 0x72cfaefeu, 0xca73c99bu, 0x57a4f122u, 0xef189647u, 0xfdad39a9u, 0x45115eccu,
+  0x764dee06u, 0xcef18963u, 0xdc44268du, 0x64f841e8u, 0xf92f7951u, 0x41931e34u, 0x5326b1dau, 0xeb9ad6bfu,
+  0xb3f9c6e9u, 0x0b45a18cu, 0x19f00e62u, 0xa14c6907u, 0x3c9b51beu, 0x842736dbu, 0x96929935u, 0x2e2efe50u,
+  0x2654b999u, 0x9ee8defcu, 0x8c5d7112u, 0x34e11677u, 0xa9362eceu, 0x118a49abu, 0x033fe645u, 0xbb838120u,
+  0xe3e09176u, 0x5b5cf613u, 0x49e959fdu, 0xf1553e98u, 0x6c820621u, 0xd43e6144u, 0xc68bceaau, 0x7e37a9cfu,
+  0xd67f4138u, 0x6ec3265du, 0x7c7689b3u, 0xc4caeed6u, 0x591dd66fu, 0xe1a1b10au, 0xf3141ee4u, 0x4ba87981u,
+  0x13cb69d7u, 0xab770eb2u, 0xb9c2a15cu, 0x017ec639u, 0x9ca9fe80u, 0x241599e5u, 0x36a0360bu, 0x8e1c516eu,
+  0x866616a7u, 0x3eda71c2u, 0x2c6fde2cu, 0x94d3b949u, 0x090481f0u, 0xb1b8e695u, 0xa30d497bu, 0x1bb12e1eu,
+  0x43d23e48u, 0xfb6e592du, 0xe9dbf6c3u, 0x516791a6u, 0xccb0a91fu, 0x740cce7au, 0x66b96194u, 0xde0506f1u
+};
+
+static const unsigned lodepng_crc32_table4[256] = {
+  0x00000000u, 0x3d6029b0u, 0x7ac05360u, 0x47a07ad0u, 0xf580a6c0u, 0xc8e08f70u, 0x8f40f5a0u, 0xb220dc10u,
+  0x30704bc1u, 0x0d106271u, 0x4ab018a1u, 0x77d03111u, 0xc5f0ed01u, 0xf890c4b1u, 0xbf30be61u, 0x825097d1u,
+  0x60e09782u, 0x5d80be32u, 0x1a20c4e2u, 0x2740ed52u, 0x95603142u, 0xa80018f2u, 0xefa06222u, 0xd2c04b92u,
+  0x5090dc43u, 0x6df0f5f3u, 0x2a508f23u, 0x1730a693u, 0xa5107a83u, 0x98705333u, 0xdfd029e3u, 0xe2b00053u,
+  0xc1c12f04u, 0xfca106b4u, 0xbb017c64u, 0x866155d4u, 0x344189c4u, 0x0921a074u, 0x4e81daa4u, 0x73e1f314u,
+  0xf1b164c5u, 0xccd14d75u, 0x8b7137a5u, 0xb6111e15u, 0x0431c205u, 0x3951ebb5u, 0x7ef19165u, 0x4391b8d5u,
+  0xa121b886u, 0x9c419136u, 0xdbe1ebe6u, 0xe681c256u, 0x54a11e46u, 0x69c137f6u, 0x2e614d26u, 0x13016496u,
+  0x9151f347u, 0xac31daf7u, 0xeb91a027u, 0xd6f18997u, 0x64d15587u, 0x59b17c37u, 0x1e1106e7u, 0x23712f57u,
+  0x58f35849u, 0x659371f9u, 0x22330b29u, 0x1f532299u, 0xad73fe89u, 0x9013d739u, 0xd7b3ade9u, 0xead38459u,
+  0x68831388u, 0x55e33a38u, 0x124340e8u, 0x2f236958u, 0x9d03b548u, 0xa0639cf8u, 0xe7c3e628u, 0xdaa3cf98u,
+  0x3813cfcbu, 0x0573e67bu, 0x42d39cabu, 0x7fb3b51bu, 0xcd93690bu, 0xf0f340bbu, 0xb7533a6bu, 0x8a3313dbu,
+  0x0863840au, 0x3503adbau, 0x72a3d76au, 0x4fc3fedau, 0xfde322cau, 0xc0830b7au, 0x872371aau, 0xba43581au,
+  0x9932774du, 0xa4525efdu, 0xe3f2242du, 0xde920d9du, 0x6cb2d18du, 0x51d2f83du, 0x167282edu, 0x2b12ab5du,
+  0xa9423c8cu, 0x9422153cu, 0xd3826fecu, 0xeee2465cu, 0x5cc29a4cu, 0x61a2b3fcu, 0x2602c92cu, 0x1b62e09cu,
+  0xf9d2e0cfu, 0xc4b2c97fu, 0x8312b3afu, 0xbe729a1fu, 0x0c52460fu, 0x31326fbfu, 0x7692156fu, 0x4bf23cdfu,
+  0xc9a2ab0eu, 0xf4c282beu, 0xb362f86eu, 0x8e02d1deu, 0x3c220dceu, 0x0142247eu, 0x46e25eaeu, 0x7b82771eu,
+  0xb1e6b092u, 0x8c869922u, 0xcb26e3f2u, 0xf646ca42u, 0x44661652u, 0x79063fe2u, 0x3ea64532u, 0x03c66c82u,
+  0x8196fb53u, 0xbcf6d2e3u, 0xfb56a833u, 0xc6368183u, 0x74165d93u, 0x49767423u, 0x0ed60ef3u, 0x33b62743u,
+  0xd1062710u, 0xec660ea0u, 0xabc67470u, 0x96a65dc0u, 0x248681d0u, 0x19e6a860u, 0x5e46d2b0u, 0x6326fb00u,
+  0xe1766cd1u, 0xdc164561u, 0x9bb63fb1u, 0xa6d61601u, 0x14f6ca11u, 0x2996e3a1u, 0x6e369971u, 0x5356b0c1u,
+  0x70279f96u, 0x4d47b626u, 0x0ae7ccf6u, 0x3787e546u, 0x85a73956u, 0xb8c710e6u, 0xff676a36u, 0xc2074386u,
+  0x4057d457u, 0x7d37fde7u, 0x3a978737u, 0x07f7ae87u, 0xb5d77297u, 0x88b75b27u, 0xcf1721f7u, 0xf2770847u,
+  0x10c70814u, 0x2da721a4u, 0x6a075b74u, 0x576772c4u, 0xe547aed4u, 0xd8278764u, 0x9f87fdb4u, 0xa2e7d404u,
+  0x20b743d5u, 0x1dd76a65u, 0x5a7710b5u, 0x67173905u, 0xd537e515u, 0xe857cca5u, 0xaff7b675u, 0x92979fc5u,
+  0xe915e8dbu, 0xd475c16bu, 0x93d5bbbbu, 0xaeb5920bu, 0x1c954e1bu, 0x21f567abu, 0x66551d7bu, 0x5b3534cbu,
+  0xd965a31au, 0xe4058aaau, 0xa3a5f07au, 0x9ec5d9cau, 0x2ce505dau, 0x11852c6au, 0x562556bau, 0x6b457f0au,
+  0x89f57f59u, 0xb49556e9u, 0xf3352c39u, 0xce550589u, 0x7c75d999u, 0x4115f029u, 0x06b58af9u, 0x3bd5a349u,
+  0xb9853498u, 0x84e51d28u, 0xc34567f8u, 0xfe254e48u, 0x4c059258u, 0x7165bbe8u, 0x36c5c138u, 0x0ba5e888u,
+  0x28d4c7dfu, 0x15b4ee6fu, 0x521494bfu, 0x6f74bd0fu, 0xdd54611fu, 0xe03448afu, 0xa794327fu, 0x9af41bcfu,
+  0x18a48c1eu, 0x25c4a5aeu, 0x6264df7eu, 0x5f04f6ceu, 0xed242adeu, 0xd044036eu, 0x97e479beu, 0xaa84500eu,
+  0x4834505du, 0x755479edu, 0x32f4033du, 0x0f942a8du, 0xbdb4f69du, 0x80d4df2du, 0xc774a5fdu, 0xfa148c4du,
+  0x78441b9cu, 0x4524322cu, 0x028448fcu, 0x3fe4614cu, 0x8dc4bd5cu, 0xb0a494ecu, 0xf704ee3cu, 0xca64c78cu
+};
+
+static const unsigned lodepng_crc32_table5[256] = {
+  0x00000000u, 0xcb5cd3a5u, 0x4dc8a10bu, 0x869472aeu, 0x9b914216u, 0x50cd91b3u, 0xd659e31du, 0x1d0530b8u,
+  0xec53826du, 0x270f51c8u, 0xa19b2366u, 0x6ac7f0c3u, 0x77c2c07bu, 0xbc9e13deu, 0x3a0a6170u, 0xf156b2d5u,
+  0x03d6029bu, 0xc88ad13eu, 0x4e1ea390u, 0x85427035u, 0x9847408du, 0x531b9328u, 0xd58fe186u, 0x1ed33223u,
+  0xef8580f6u, 0x24d95353u, 0xa24d21fdu, 0x6911f258u, 0x7414c2e0u, 0xbf481145u, 0x39dc63ebu, 0xf280b04eu,
+  0x07ac0536u, 0xccf0d693u, 0x4a64a43du, 0x81387798u, 0x9c3d4720u, 0x57619485u, 0xd1f5e62bu, 0x1aa9358eu,
+  0xebff875bu, 0x20a354feu, 0xa6372650u, 0x6d6bf5f5u, 0x706ec54du, 0xbb3216e8u, 0x3da66446u, 0xf6fab7e3u,
+  0x047a07adu, 0xcf26d408u, 0x49b2a6a6u, 0x82ee7503u, 0x9feb45bbu, 0x54b7961eu, 0xd223e4b0u, 0x197f3715u,
+  0xe82985c0u, 0x23755665u, 0xa5e124cbu, 0x6ebdf76eu, 0x73b8c7d6u, 0xb8e41473u, 0x3e7066ddu, 0xf52cb578u,
+  0x0f580a6cu, 0xc404d9c9u, 0x4290ab67u, 0x89cc78c2u, 0x94c9487au, 0x5f959bdfu, 0xd901e971u, 0x125d3ad4u,
+  0xe30b8801u, 0x28575ba4u, 0xaec3290au, 0x659ffaafu, 0x789aca17u, 0xb3c619b2u, 0x35526b1cu, 0xfe0eb8b9u,
+  0x0c8e08f7u, 0xc7d2db52u, 0x4146a9fcu, 0x8a1a7a59u, 0x971f4ae1u, 0x5c439944u, 0xdad7ebeau, 0x118b384fu,
+  0xe0dd8a9au, 0x2b81593fu, 0xad152b91u, 0x6649f834u, 0x7b4cc88cu, 0xb0101b29u, 0x36846987u, 0xfdd8ba22u,
+  0x08f40f5au, 0xc3a8dcffu, 0x453cae51u, 0x8e607df4u, 0x93654d4cu, 0x58399ee9u, 0xdeadec47u, 0x15f13fe2u,
+  0xe4a78d37u, 0x2ffb5e92u, 0xa96f2c3cu, 0x6233ff99u, 0x7f36cf21u, 0xb46a1c84u, 0x32fe6e2au, 0xf9a2bd8fu,
+  0x0b220dc1u, 0xc07ede64u, 0x46eaaccau, 0x8db67f6fu, 0x90b34fd7u, 0x5bef9c72u, 0xdd7beedcu, 0x16273d79u,
+  0xe7718facu, 0x2c2d5c09u, 0xaab92ea7u, 0x61e5fd02u, 0x7ce0cdbau, 0xb7bc1e1fu, 0x31286cb1u, 0xfa74bf14u,
+  0x1eb014d8u, 0xd5ecc77du, 0x5378b5d3u, 0x98246676u, 0x852156ceu, 0x4e7d856bu, 0xc8e9f7c5u, 0x03b52460u,
+  0xf2e396b5u, 0x39bf4510u, 0xbf2b37beu, 0x7477e41bu, 0x6972d4a3u, 0xa22e0706u, 0x24ba75a8u, 0xefe6a60du,
+  0x1d661643u, 0xd63ac5e6u, 0x50aeb748u, 0x9bf264edu, 0x86f75455u, 0x4dab87f0u, 0xcb3ff55eu, 0x006326fbu,
+  0xf135942eu, 0x3a69478bu, 0xbcfd3525u, 0x77a1e680u, 0x6aa4d638u, 0xa1f8059du, 0x276c7733u, 0xec30a496u,
+  0x191c11eeu, 0xd240c24bu, 0x54d4b0e5u, 0x9f886340u, 0x828d53f8u, 0x49d1805du, 0xcf45f2f3u, 0x04192156u,
+  0xf54f9383u, 0x3e134026u, 0xb8873288u, 0x73dbe12du, 0x6eded195u, 0xa5820230u, 0x2316709eu, 0xe84aa33bu,
+  0x1aca1375u, 0xd196c0d0u, 0x5702b27eu, 0x9c5e61dbu, 0x815b5163u, 0x4a0782c6u, 0xcc93f068u, 0x07cf23cdu,
+  0xf6999118u, 0x3dc542bdu, 0xbb513013u, 0x700de3b6u, 0x6d08d30eu, 0xa65400abu, 0x20c07205u, 0xeb9ca1a0u,
+  0x11e81eb4u, 0xdab4cd11u, 0x5c20bfbfu, 0x977c6c1au, 0x8a795ca2u, 0x41258f07u, 0xc7b1fda9u, 0x0ced2e0cu,
+  0xfdbb9cd9u, 0x36e74f7cu, 0xb0733dd2u, 0x7b2fee77u, 0x662adecfu, 0xad760d6au, 0x2be27fc4u, 0xe0beac61u,
+  0x123e1c2fu, 0xd962cf8au, 0x5ff6bd24u, 0x94aa6e81u, 0x89af5e39u, 0x42f38d9cu, 0xc467ff32u, 0x0f3b2c97u,
+  0xfe6d9e42u, 0x35314de7u, 0xb3a53f49u, 0x78f9ececu, 0x65fcdc54u, 0xaea00ff1u, 0x28347d5fu, 0xe368aefau,
+  0x16441b82u, 0xdd18c827u, 0x5b8cba89u, 0x90d0692cu, 0x8dd55994u, 0x46898a31u, 0xc01df89fu, 0x0b412b3au,
+  0xfa1799efu, 0x314b4a4au, 0xb7df38e4u, 0x7c83eb41u, 0x6186dbf9u, 0xaada085cu, 0x2c4e7af2u, 0xe712a957u,
+  0x15921919u, 0xdececabcu, 0x585ab812u, 0x93066bb7u, 0x8e035b0fu, 0x455f88aau, 0xc3cbfa04u, 0x089729a1u,
+  0xf9c19b74u, 0x329d48d1u, 0xb4093a7fu, 0x7f55e9dau, 0x6250d962u, 0xa90c0ac7u, 0x2f987869u, 0xe4c4abccu
+};
+
+static const unsigned lodepng_crc32_table6[256] = {
+  0x00000000u, 0xa6770bb4u, 0x979f1129u, 0x31e81a9du, 0xf44f2413u, 0x52382fa7u, 0x63d0353au, 0xc5a73e8eu,
+  0x33ef4e67u, 0x959845d3u, 0xa4705f4eu, 0x020754fau, 0xc7a06a74u, 0x61d761c0u, 0x503f7b5du, 0xf64870e9u,
+  0x67de9cceu, 0xc1a9977au, 0xf0418de7u, 0x56368653u, 0x9391b8ddu, 0x35e6b369u, 0x040ea9f4u, 0xa279a240u,
+  0x5431d2a9u, 0xf246d91du, 0xc3aec380u, 0x65d9c834u, 0xa07ef6bau, 0x0609fd0eu, 0x37e1e793u, 0x9196ec27u,
+  0xcfbd399cu, 0x69ca3228u, 0x582228b5u, 0xfe552301u, 0x3bf21d8fu, 0x9d85163bu, 0xac6d0ca6u, 0x0a1a0712u,
+  0xfc5277fbu, 0x5a257c4fu, 0x6bcd66d2u, 0xcdba6d66u, 0x081d53e8u, 0xae6a585cu, 0x9f8242c1u, 0x39f54975u,
+  0xa863a552u, 0x0e14aee6u, 0x3ffcb47bu, 0x998bbfcfu, 0x5c2c8141u, 0xfa5b8af5u, 0xcbb39068u, 0x6dc49bdcu,
+  0x9b8ceb35u, 0x3dfbe081u, 0x0c13fa1cu, 0xaa64f1a8u, 0x6fc3cf26u, 0xc9b4c492u, 0xf85cde0fu, 0x5e2bd5bbu,
+  0x440b7579u, 0xe27c7ecdu, 0xd3946450u, 0x75e36fe4u, 0xb044516au, 0x16335adeu, 0x27db4043u, 0x81ac4bf7u,
+  0x77e43b1eu, 0xd19330aau, 0xe07b2a37u, 0x460c2183u, 0x83ab1f0du, 0x25dc14b9u, 0x14340e24u, 0xb2430590u,
+  0x23d5e9b7u, 0x85a2e203u, 0xb44af89eu, 0x123df32au, 0xd79acda4u, 0x71edc610u, 0x4005dc8du, 0xe672d739u,
+  0x103aa7d0u, 0xb64dac64u, 0x87a5b6f9u, 0x21d2bd4du, 0xe47583c3u, 0x42028877u, 0x73ea92eau, 0xd59d995eu,
+  0x8bb64ce5u, 0x2dc14751u, 0x1c295dccu, 0xba5e5678u, 0x7ff968f6u, 0xd98e6342u, 0xe86679dfu, 0x4e11726bu,
+  0xb8590282u, 0x1e2e0936u, 0x2fc613abu, 0x89b1181fu, 0x4c162691u, 0xea612d25u, 0xdb8937b8u, 0x7dfe3c0cu,
+  0xec68d02bu, 0x4a1fdb9fu, 0x7bf7c102u, 0xdd80cab6u, 0x1827f438u, 0xbe50ff8cu, 0x8fb8e511u, 0x29cfeea5u,
+  0xdf879e4cu, 0x79f095f8u, 0x48188f65u, 0xee6f84d1u, 0x2bc8ba5fu, 0x8dbfb1ebu, 0xbc57ab76u, 0x1a20a0c2u,
+  0x8816eaf2u, 0x2e61e146u, 0x1f89fbdbu, 0xb9fef06fu, 0x7c59cee1u, 0xda2ec555u, 0xebc6dfc8u, 0x4db1d47cu,
+  0xbbf9a495u, 0x1d8eaf21u, 0x2c66b5bcu, 0x8a11be08u, 0x4fb68086u, 0xe9c18b32u, 0xd82991afu, 0x7e5e9a1bu,
+  0xefc8763cu, 0x49bf7d88u, 0x78576715u, 0xde206ca1u, 0x1b87522fu, 0xbdf0599bu, 0x8c184306u, 0x2a6f48b2u,
+  0xdc27385bu, 0x7a5033efu, 0x4bb82972u, 0xedcf22c6u, 0x28681c48u, 0x8e1f17fcu, 0xbff70d61u, 0x198006d5u,
+  0x47abd36eu, 0xe1dcd8dau, 0xd034c247u, 0x7643c9f3u, 0xb3e4f77du, 0x1593fcc9u, 0x247be654u, 0x820cede0u,
+  0x74449d09u, 0xd23396bdu, 0xe3db8c20u, 0x45ac8794u, 0x800bb91au, 0x267cb2aeu, 0x1794a833u, 0xb1e3a387u,
+  0x20754fa0u, 0x86024414u, 0xb7ea5e89u, 0x119d553du, 0xd43a6bb3u, 0x724d6007u, 0x43a57a9au, 0xe5d2712eu,
+  0x139a01c7u, 0xb5ed0a73u, 0x840510eeu, 0x22721b5au, 0xe7d525d4u, 0x41a22e60u, 0x704a34fdu, 0xd63d3f49u,
+  0xcc1d9f8bu, 0x6a6a943fu, 0x5b828ea2u, 0xfdf58516u, 0x3852bb98u, 0x9e25b02cu, 0xafcdaab1u, 0x09baa105u,
+  0xfff2d1ecu, 0x5985da58u, 0x686dc0c5u, 0xce1acb71u, 0x0bbdf5ffu, 0xadcafe4bu, 0x9c22e4d6u, 0x3a55ef62u,
+  0xabc30345u, 0x0db408f1u, 0x3c5c126cu, 0x9a2b19d8u, 0x5f8c2756u, 0xf9fb2ce2u, 0xc813367fu, 0x6e643dcbu,
+  0x982c4d22u, 0x3e5b4696u, 0x0fb35c0bu, 0xa9c457bfu, 0x6c636931u, 0xca146285u, 0xfbfc7818u, 0x5d8b73acu,
+  0x03a0a617u, 0xa5d7ada3u, 0x943fb73eu, 0x3248bc8au, 0xf7ef8204u, 0x519889b0u, 0x6070932du, 0xc6079899u,
+  0x304fe870u, 0x9638e3c4u, 0xa7d0f959u, 0x01a7f2edu, 0xc400cc63u, 0x6277c7d7u, 0x539fdd4au, 0xf5e8d6feu,
+  0x647e3ad9u, 0xc209316du, 0xf3e12bf0u, 0x55962044u, 0x90311ecau, 0x3646157eu, 0x07ae0fe3u, 0xa1d90457u,
+  0x579174beu, 0xf1e67f0au, 0xc00e6597u, 0x66796e23u, 0xa3de50adu, 0x05a95b19u, 0x34414184u, 0x92364a30u
+};
+
+static const unsigned lodepng_crc32_table7[256] = {
+  0x00000000u, 0xccaa009eu, 0x4225077du, 0x8e8f07e3u, 0x844a0efau, 0x48e00e64u, 0xc66f0987u, 0x0ac50919u,
+  0xd3e51bb5u, 0x1f4f1b2bu, 0x91c01cc8u, 0x5d6a1c56u, 0x57af154fu, 0x9b0515d1u, 0x158a1232u, 0xd92012acu,
+  0x7cbb312bu, 0xb01131b5u, 0x3e9e3656u, 0xf23436c8u, 0xf8f13fd1u, 0x345b3f4fu, 0xbad438acu, 0x767e3832u,
+  0xaf5e2a9eu, 0x63f42a00u, 0xed7b2de3u, 0x21d12d7du, 0x2b142464u, 0xe7be24fau, 0x69312319u, 0xa59b2387u,
+  0xf9766256u, 0x35dc62c8u, 0xbb53652bu, 0x77f965b5u, 0x7d3c6cacu, 0xb1966c32u, 0x3f196bd1u, 0xf3b36b4fu,
+  0x2a9379e3u, 0xe639797du, 0x68b67e9eu, 0xa41c7e00u, 0xaed97719u, 0x62737787u, 0xecfc7064u, 0x205670fau,
+  0x85cd537du, 0x496753e3u, 0xc7e85400u, 0x0b42549eu, 0x01875d87u, 0xcd2d5d19u, 0x43a25afau, 0x8f085a64u,
+  0x562848c8u, 0x9a824856u, 0x140d4fb5u, 0xd8a74f2bu, 0xd2624632u, 0x1ec846acu, 0x9047414fu, 0x5ced41d1u,
+  0x299dc2edu, 0xe537c273u, 0x6bb8c590u, 0xa712c50eu, 0xadd7cc17u, 0x617dcc89u, 0xeff2cb6au, 0x2358cbf4u,
+  0xfa78d958u, 0x36d2d9c6u, 0xb85dde25u, 0x74f7debbu, 0x7e32d7a2u, 0xb298d73cu, 0x3c17d0dfu, 0xf0bdd041u,
+  0x5526f3c6u, 0x998cf358u, 0x1703f4bbu, 0xdba9f425u, 0xd16cfd3cu, 0x1dc6fda2u, 0x9349fa41u, 0x5fe3fadfu,
+  0x86c3e873u, 0x4a69e8edu, 0xc4e6ef0eu, 0x084cef90u, 0x0289e689u, 0xce23e617u, 0x40ace1f4u, 0x8c06e16au,
+  0xd0eba0bbu, 0x1c41a025u, 0x92cea7c6u, 0x5e64a758u, 0x54a1ae41u, 0x980baedfu, 0x1684a93cu, 0xda2ea9a2u,
+  0x030ebb0eu, 0xcfa4bb90u, 0x412bbc73u, 0x8d81bcedu, 0x8744b5f4u, 0x4beeb56au, 0xc561b289u, 0x09cbb217u,
+  0xac509190u, 0x60fa910eu, 0xee7596edu, 0x22df9673u, 0x281a9f6au, 0xe4b09ff4u, 0x6a3f9817u, 0xa6959889u,
+  0x7fb58a25u, 0xb31f8abbu, 0x3d908d58u, 0xf13a8dc6u, 0xfbff84dfu, 0x37558441u, 0xb9da83a2u, 0x7570833cu,
+  0x533b85dau, 0x9f918544u, 0x111e82a7u, 0xddb48239u, 0xd7718b20u, 0x1bdb8bbeu, 0x95548c5du, 0x59fe8cc3u,
+  0x80de9e6fu, 0x4c749ef1u, 0xc2fb9912u, 0x0e51998cu, 0x04949095u, 0xc83e900bu, 0x46b197e8u, 0x8a1b9776u,
+  0x2f80b4f1u, 0xe32ab46fu, 0x6da5b38cu, 0xa10fb312u, 0xabcaba0bu, 0x6760ba95u, 0xe9efbd76u, 0x2545bde8u,
+  0xfc65af44u, 0x30cfafdau, 0xbe40a839u, 0x72eaa8a7u, 0x782fa1beu, 0xb485a120u, 0x3a0aa6c3u, 0xf6a0a65du,
+  0xaa4de78cu, 0x66e7e712u, 0xe868e0f1u, 0x24c2e06fu, 0x2e07e976u, 0xe2ade9e8u, 0x6c22ee0bu, 0xa088ee95u,
+  0x79a8fc39u, 0xb502fca7u, 0x3b8dfb44u, 0xf727fbdau, 0xfde2f2c3u, 0x3148f25du, 0xbfc7f5beu, 0x736df520u,
+  0xd6f6d6a7u, 0x1a5cd639u, 0x94d3d1dau, 0x5879d144u, 0x52bcd85du, 0x9e16d8c3u, 0x1099df20u, 0xdc33dfbeu,
+  0x0513cd12u, 0xc9b9cd8cu, 0x4736ca6fu, 0x8b9ccaf1u, 0x8159c3e8u, 0x4df3c376u, 0xc37cc495u, 0x0fd6c40bu,
+  0x7aa64737u, 0xb60c47a9u, 0x3883404au, 0xf42940d4u, 0xfeec49cdu, 0x32464953u, 0xbcc94eb0u, 0x70634e2eu,
+  0xa9435c82u, 0x65e95c1cu, 0xeb665bffu, 0x27cc5b61u, 0x2d095278u, 0xe1a352e6u, 0x6f2c5505u, 0xa386559bu,
+  0x061d761cu, 0xcab77682u, 0x44387161u, 0x889271ffu, 0x825778e6u, 0x4efd7878u, 0xc0727f9bu, 0x0cd87f05u,
+  0xd5f86da9u, 0x19526d37u, 0x97dd6ad4u, 0x5b776a4au, 0x51b26353u, 0x9d1863cdu, 0x1397642eu, 0xdf3d64b0u,
+  0x83d02561u, 0x4f7a25ffu, 0xc1f5221cu, 0x0d5f2282u, 0x079a2b9bu, 0xcb302b05u, 0x45bf2ce6u, 0x89152c78u,
+  0x50353ed4u, 0x9c9f3e4au, 0x121039a9u, 0xdeba3937u, 0xd47f302eu, 0x18d530b0u, 0x965a3753u, 0x5af037cdu,
+  0xff6b144au, 0x33c114d4u, 0xbd4e1337u, 0x71e413a9u, 0x7b211ab0u, 0xb78b1a2eu, 0x39041dcdu, 0xf5ae1d53u,
+  0x2c8e0fffu, 0xe0240f61u, 0x6eab0882u, 0xa201081cu, 0xa8c40105u, 0x646e019bu, 0xeae10678u, 0x264b06e6u
+};
+
+/* Computes the cyclic redundancy check as used by PNG chunks*/
 unsigned lodepng_crc32(const unsigned char* data, size_t length) {
+  /*Using the Slicing by Eight algorithm*/
   unsigned r = 0xffffffffu;
-  size_t i;
-  for(i = 0; i < length; ++i) {
-    r = lodepng_crc32_table[(r ^ data[i]) & 0xffu] ^ (r >> 8u);
+  while(length >= 8) {
+    r = lodepng_crc32_table7[(data[0] ^ (r & 0xffu))] ^
+        lodepng_crc32_table6[(data[1] ^ ((r >> 8) & 0xffu))] ^
+        lodepng_crc32_table5[(data[2] ^ ((r >> 16) & 0xffu))] ^
+        lodepng_crc32_table4[(data[3] ^ ((r >> 24) & 0xffu))] ^
+        lodepng_crc32_table3[data[4]] ^
+        lodepng_crc32_table2[data[5]] ^
+        lodepng_crc32_table1[data[6]] ^
+        lodepng_crc32_table0[data[7]];
+    data += 8;
+    length -= 8;
+  }
+  while(length--) {
+    r = lodepng_crc32_table0[(r ^ *data++) & 0xffu] ^ (r >> 8);
   }
   return r ^ 0xffffffffu;
 }
 #else /* LODEPNG_COMPILE_CRC */
 /*in this case, the function is only declared here, and must be defined externally
-so that it will be linked in*/
+so that it will be linked in.
+
+Example implementation that uses a much smaller lookup table for memory constrained cases:
+
+unsigned lodepng_crc32(const unsigned char* data, size_t length) {
+  unsigned r = 0xffffffffu;
+  static const unsigned table[16] = {
+    0x00000000, 0x1db71064, 0x3b6e20c8, 0x26d930ac, 0x76dc4190, 0x6b6b51f4, 0x4db26158, 0x5005713c,
+    0xedb88320, 0xf00f9344, 0xd6d6a3e8, 0xcb61b38c, 0x9b64c2b0, 0x86d3d2d4, 0xa00ae278, 0xbdbdf21c
+  };
+  while(length--) {
+    r = table[(r ^ *data) & 0xf] ^ (r >> 4);
+    r = table[(r ^ (*data >> 4)) & 0xf] ^ (r >> 4);
+    data++;
+  }
+  return r ^ 0xffffffffu;
+}
+*/
 unsigned lodepng_crc32(const unsigned char* data, size_t length);
 #endif /* LODEPNG_COMPILE_CRC */
 
@@ -3964,15 +4237,14 @@ static unsigned auto_choose_color(LodePNGColorMode* mode_out,
 
 #endif /* #ifdef LODEPNG_COMPILE_ENCODER */
 
-/*
-Paeth predictor, used by PNG filter type 4
-The parameters are of type short, but should come from unsigned chars, the shorts
-are only needed to make the paeth calculation correct.
-*/
-static unsigned char paethPredictor(short a, short b, short c) {
-  short pa = LODEPNG_ABS(b - c);
-  short pb = LODEPNG_ABS(a - c);
-  short pc = LODEPNG_ABS(a + b - c - c);
+/*Paeth predictor, used by PNG filter type 4*/
+static unsigned char paethPredictor(unsigned char a, unsigned char b, unsigned char c) {
+  /* the subtractions of unsigned char cast it to a signed type.
+  With gcc, short is faster than int, with clang int is as fast (as of april 2023)*/
+  short pa = (b - c) < 0 ? -(b - c) : (b - c);
+  short pb = (a - c) < 0 ? -(a - c) : (a - c);
+  /* writing it out like this compiles to something faster than introducing a temp variable*/
+  short pc = (a + b - c - c) < 0 ? -(a + b - c - c) : (a + b - c - c);
   /* return input value associated with smallest of pa, pb, pc (with certain priority if equal) */
   if(pb < pa) { a = b; pa = pb; }
   return (pc < pa) ? c : a;
@@ -4168,47 +4440,108 @@ static unsigned unfilterScanline(unsigned char* recon, const unsigned char* scan
       break;
     case 4:
       if(precon) {
-        size_t j = 0;
-        for(i = 0; i != bytewidth; ++i) {
-          recon[i] = (scanline[i] + precon[i]); /*paethPredictor(0, precon[i], 0) is always precon[i]*/
-        }
-
-        /* Unroll independent paths of the paeth predictor. A 6x and 8x version is also possible but that
-        adds too much code. Whether this speeds up anything depends on compiler and settings. */
-        if(bytewidth >= 4) {
-          for(; i + 3 < length; i += 4, j += 4) {
-            unsigned char s0 = scanline[i + 0], s1 = scanline[i + 1], s2 = scanline[i + 2], s3 = scanline[i + 3];
-            unsigned char r0 = recon[j + 0], r1 = recon[j + 1], r2 = recon[j + 2], r3 = recon[j + 3];
-            unsigned char p0 = precon[i + 0], p1 = precon[i + 1], p2 = precon[i + 2], p3 = precon[i + 3];
-            unsigned char q0 = precon[j + 0], q1 = precon[j + 1], q2 = precon[j + 2], q3 = precon[j + 3];
-            recon[i + 0] = s0 + paethPredictor(r0, p0, q0);
-            recon[i + 1] = s1 + paethPredictor(r1, p1, q1);
-            recon[i + 2] = s2 + paethPredictor(r2, p2, q2);
-            recon[i + 3] = s3 + paethPredictor(r3, p3, q3);
+        /* Unroll independent paths of this predictor. Whether this speeds up
+        anything depends on compiler and settings. */
+        if(bytewidth == 8) {
+          unsigned char a0, b0 = 0, c0, d0 = 0, a1, b1 = 0, c1, d1 = 0;
+          unsigned char a2, b2 = 0, c2, d2 = 0, a3, b3 = 0, c3, d3 = 0;
+          unsigned char a4, b4 = 0, c4, d4 = 0, a5, b5 = 0, c5, d5 = 0;
+          unsigned char a6, b6 = 0, c6, d6 = 0, a7, b7 = 0, c7, d7 = 0;
+          for(i = 0; i + 7 < length; i += 8) {
+            c0 = b0; c1 = b1; c2 = b2; c3 = b3;
+            c4 = b4; c5 = b5; c6 = b6; c7 = b7;
+            b0 = precon[i + 0]; b1 = precon[i + 1]; b2 = precon[i + 2]; b3 = precon[i + 3];
+            b4 = precon[i + 4]; b5 = precon[i + 5]; b6 = precon[i + 6]; b7 = precon[i + 7];
+            a0 = d0; a1 = d1; a2 = d2; a3 = d3;
+            a4 = d4; a5 = d5; a6 = d6; a7 = d7;
+            d0 = scanline[i + 0] + paethPredictor(a0, b0, c0);
+            d1 = scanline[i + 1] + paethPredictor(a1, b1, c1);
+            d2 = scanline[i + 2] + paethPredictor(a2, b2, c2);
+            d3 = scanline[i + 3] + paethPredictor(a3, b3, c3);
+            d4 = scanline[i + 4] + paethPredictor(a4, b4, c4);
+            d5 = scanline[i + 5] + paethPredictor(a5, b5, c5);
+            d6 = scanline[i + 6] + paethPredictor(a6, b6, c6);
+            d7 = scanline[i + 7] + paethPredictor(a7, b7, c7);
+            recon[i + 0] = d0; recon[i + 1] = d1; recon[i + 2] = d2; recon[i + 3] = d3;
+            recon[i + 4] = d4; recon[i + 5] = d5; recon[i + 6] = d6; recon[i + 7] = d7;
           }
-        } else if(bytewidth >= 3) {
-          for(; i + 2 < length; i += 3, j += 3) {
-            unsigned char s0 = scanline[i + 0], s1 = scanline[i + 1], s2 = scanline[i + 2];
-            unsigned char r0 = recon[j + 0], r1 = recon[j + 1], r2 = recon[j + 2];
-            unsigned char p0 = precon[i + 0], p1 = precon[i + 1], p2 = precon[i + 2];
-            unsigned char q0 = precon[j + 0], q1 = precon[j + 1], q2 = precon[j + 2];
-            recon[i + 0] = s0 + paethPredictor(r0, p0, q0);
-            recon[i + 1] = s1 + paethPredictor(r1, p1, q1);
-            recon[i + 2] = s2 + paethPredictor(r2, p2, q2);
+        } else if(bytewidth == 6) {
+          unsigned char a0, b0 = 0, c0, d0 = 0, a1, b1 = 0, c1, d1 = 0;
+          unsigned char a2, b2 = 0, c2, d2 = 0, a3, b3 = 0, c3, d3 = 0;
+          unsigned char a4, b4 = 0, c4, d4 = 0, a5, b5 = 0, c5, d5 = 0;
+          for(i = 0; i + 5 < length; i += 6) {
+            c0 = b0; c1 = b1; c2 = b2;
+            c3 = b3; c4 = b4; c5 = b5;
+            b0 = precon[i + 0]; b1 = precon[i + 1]; b2 = precon[i + 2];
+            b3 = precon[i + 3]; b4 = precon[i + 4]; b5 = precon[i + 5];
+            a0 = d0; a1 = d1; a2 = d2;
+            a3 = d3; a4 = d4; a5 = d5;
+            d0 = scanline[i + 0] + paethPredictor(a0, b0, c0);
+            d1 = scanline[i + 1] + paethPredictor(a1, b1, c1);
+            d2 = scanline[i + 2] + paethPredictor(a2, b2, c2);
+            d3 = scanline[i + 3] + paethPredictor(a3, b3, c3);
+            d4 = scanline[i + 4] + paethPredictor(a4, b4, c4);
+            d5 = scanline[i + 5] + paethPredictor(a5, b5, c5);
+            recon[i + 0] = d0; recon[i + 1] = d1; recon[i + 2] = d2;
+            recon[i + 3] = d3; recon[i + 4] = d4; recon[i + 5] = d5;
           }
-        } else if(bytewidth >= 2) {
-          for(; i + 1 < length; i += 2, j += 2) {
-            unsigned char s0 = scanline[i + 0], s1 = scanline[i + 1];
-            unsigned char r0 = recon[j + 0], r1 = recon[j + 1];
-            unsigned char p0 = precon[i + 0], p1 = precon[i + 1];
-            unsigned char q0 = precon[j + 0], q1 = precon[j + 1];
-            recon[i + 0] = s0 + paethPredictor(r0, p0, q0);
-            recon[i + 1] = s1 + paethPredictor(r1, p1, q1);
+        } else if(bytewidth == 4) {
+          unsigned char a0, b0 = 0, c0, d0 = 0, a1, b1 = 0, c1, d1 = 0;
+          unsigned char a2, b2 = 0, c2, d2 = 0, a3, b3 = 0, c3, d3 = 0;
+          for(i = 0; i + 3 < length; i += 4) {
+            c0 = b0; c1 = b1; c2 = b2; c3 = b3;
+            b0 = precon[i + 0]; b1 = precon[i + 1]; b2 = precon[i + 2]; b3 = precon[i + 3];
+            a0 = d0; a1 = d1; a2 = d2; a3 = d3;
+            d0 = scanline[i + 0] + paethPredictor(a0, b0, c0);
+            d1 = scanline[i + 1] + paethPredictor(a1, b1, c1);
+            d2 = scanline[i + 2] + paethPredictor(a2, b2, c2);
+            d3 = scanline[i + 3] + paethPredictor(a3, b3, c3);
+            recon[i + 0] = d0; recon[i + 1] = d1; recon[i + 2] = d2; recon[i + 3] = d3;
+          }
+        } else if(bytewidth == 3) {
+          unsigned char a0, b0 = 0, c0, d0 = 0;
+          unsigned char a1, b1 = 0, c1, d1 = 0;
+          unsigned char a2, b2 = 0, c2, d2 = 0;
+          for(i = 0; i + 2 < length; i += 3) {
+            c0 = b0; c1 = b1; c2 = b2;
+            b0 = precon[i + 0]; b1 = precon[i + 1]; b2 = precon[i + 2];
+            a0 = d0; a1 = d1; a2 = d2;
+            d0 = scanline[i + 0] + paethPredictor(a0, b0, c0);
+            d1 = scanline[i + 1] + paethPredictor(a1, b1, c1);
+            d2 = scanline[i + 2] + paethPredictor(a2, b2, c2);
+            recon[i + 0] = d0; recon[i + 1] = d1; recon[i + 2] = d2;
+          }
+        } else if(bytewidth == 2) {
+          unsigned char a0, b0 = 0, c0, d0 = 0;
+          unsigned char a1, b1 = 0, c1, d1 = 0;
+          for(i = 0; i + 1 < length; i += 2) {
+            c0 = b0; c1 = b1;
+            b0 = precon[i + 0];
+            b1 = precon[i + 1];
+            a0 = d0; a1 = d1;
+            d0 = scanline[i + 0] + paethPredictor(a0, b0, c0);
+            d1 = scanline[i + 1] + paethPredictor(a1, b1, c1);
+            recon[i + 0] = d0;
+            recon[i + 1] = d1;
+          }
+        } else if(bytewidth == 1) {
+          unsigned char a, b = 0, c, d = 0;
+          for(i = 0; i != length; ++i) {
+            c = b;
+            b = precon[i];
+            a = d;
+            d = scanline[i] + paethPredictor(a, b, c);
+            recon[i] = d;
+          }
+        } else {
+          /* Normally not a possible case, but this would handle it correctly */
+          for(i = 0; i != bytewidth; ++i) {
+            recon[i] = (scanline[i] + precon[i]); /*paethPredictor(0, precon[i], 0) is always precon[i]*/
           }
         }
-
-        for(; i != length; ++i, ++j) {
-          recon[i] = (scanline[i] + paethPredictor(recon[i - bytewidth], precon[i], precon[j]));
+        /* finish any remaining bytes */
+        for(; i != length; ++i) {
+          recon[i] = (scanline[i] + paethPredictor(recon[i - bytewidth], precon[i], precon[i - bytewidth]));
         }
       } else {
         size_t j = 0;
diff --git a/app/src/main/cpp/core/lodepng.h b/app/src/main/cpp/core/lodepng.h
index fdafc77..81d4985 100644
--- a/app/src/main/cpp/core/lodepng.h
+++ b/app/src/main/cpp/core/lodepng.h
@@ -1,7 +1,7 @@
 /*
-LodePNG version 20220717
+LodePNG version 20230410
 
-Copyright (c) 2005-2022 Lode Vandevenne
+Copyright (c) 2005-2023 Lode Vandevenne
 
 This software is provided 'as-is', without any express or implied
 warranty. In no event will the authors be held liable for any damages
@@ -92,7 +92,10 @@ or comment out LODEPNG_COMPILE_ALLOCATORS below*/
 #endif
 
 /*Disable built-in CRC function, in that case a custom implementation of
-lodepng_crc32 must be defined externally so that it can be linked in.*/
+lodepng_crc32 must be defined externally so that it can be linked in.
+The default built-in CRC code comes with 8KB of lookup tables, so for memory constrained environment you may want it
+disabled and provide a much smaller implementation externally as said above. You can find such an example implementation
+in a comment in the lodepng.c(pp) file in the 'else' case of the searchable LODEPNG_COMPILE_CRC section.*/
 #ifndef LODEPNG_NO_COMPILE_CRC
 /*pass -DLODEPNG_NO_COMPILE_CRC to the compiler to disable the built-in one,
 or comment out LODEPNG_COMPILE_CRC below*/
@@ -1909,6 +1912,7 @@ symbol.
 Not all changes are listed here, the commit history in github lists more:
 https://github.com/lvandeve/lodepng
 
+*) 10 apr 2023: faster CRC32 implementation, but with larger lookup table.
 *) 13 jun 2022: added support for the sBIT chunk.
 *) 09 jan 2022: minor decoder speed improvements.
 *) 27 jun 2021: added warnings that file reading/writing functions don't support
diff --git a/app/src/main/cpp/core/mops.c b/app/src/main/cpp/core/mops.c
index 8bf460f..dfbb2e0 100644
--- a/app/src/main/cpp/core/mops.c
+++ b/app/src/main/cpp/core/mops.c
@@ -33,17 +33,6 @@ BYTE disp = 0;								// flag for update display area
 
 static LPBYTE pbyRomView[2] = {NULL, NULL};	// HP49G ROM views
 
-// CRC calculation
-static WORD crc_table[] =
-{
-	0x0000, 0x1081, 0x2102, 0x3183, 0x4204, 0x5285, 0x6306, 0x7387,
-	0x8408, 0x9489, 0xA50A, 0xB58B, 0xC60C, 0xD68D, 0xE70E, 0xF78F
-};
-static __inline VOID UpCRC(BYTE nib)
-{
-	Chipset.crc = (WORD)((Chipset.crc>>4)^crc_table[(Chipset.crc^nib)&0xf]);
-}
-
 static __inline UINT MIN(UINT a, UINT b)
 {
 	return (a<b)?a:b;
@@ -783,7 +772,11 @@ VOID Nread(BYTE *a, DWORD d, UINT s)
 			ReadIO(a,v,c,TRUE);
 
 			// reading MSB of timer2 update the CRC register
-			if (v+c == 0x40) UpCRC(a[c-1]);	// timer2 MSB touched, update the CRC register
+			if (v+c == 0x40)				// timer2 MSB touched
+			{
+				// update the CRC register
+				Chipset.crc = UpCRC(Chipset.crc,a[c-1]);
+			}
 		}
 		else
 		{
@@ -849,7 +842,7 @@ VOID Nread(BYTE *a, DWORD d, UINT s)
 			}
 
 			for (u=0; u<c; u++)				// update CRC
-				UpCRC(a[u]);
+				Chipset.crc = UpCRC(Chipset.crc,a[u]);
 		}
 		a+=c;
 		d=(d+c)&0xFFFFF;
@@ -1145,6 +1138,22 @@ VOID ReadIO(BYTE *a, DWORD d, DWORD s, BOOL bUpdate)
 			break;
 		case 0x12: // TCS
 			*a = Chipset.IORam[d];			// return TCS value
+
+			if ((*a & TBF))					// Transmit buffer full
+			{
+				// the G-series XModem implementation has a timeout loop counter
+				// waiting for transmit buffer empty, so on fast hosts with
+				// CPU running with max. speed we may get a timeout overflow
+				// -> to avoid this slow down CPU speed on transmit buffer full
+
+				InitAdjustSpeed();			// init variables if necessary
+				EnterCriticalSection(&csSlowLock);
+				{
+					nOpcSlow = 10;			// slow down next 10 opcodes
+				}
+				LeaveCriticalSection(&csSlowLock);
+			}
+
 			#if defined DEBUG_SERIAL
 			if (bUpdate)
 			{
diff --git a/app/src/main/cpp/core/pch.h b/app/src/main/cpp/core/pch.h
index a905b1c..555374a 100644
--- a/app/src/main/cpp/core/pch.h
+++ b/app/src/main/cpp/core/pch.h
@@ -61,6 +61,24 @@ typedef ULONG  ULONG_PTR, *PULONG_PTR;
 typedef LONG   LONG_PTR,  *PLONG_PTR;
 #endif
 
+#if !defined PROCESS_POWER_THROTTLING_CURRENT_VERSION
+#define PROCESS_POWER_THROTTLING_CURRENT_VERSION 1
+#endif
+
+#if !defined PROCESS_POWER_THROTTLING_IGNORE_TIMER_RESOLUTION
+#define PROCESS_POWER_THROTTLING_IGNORE_TIMER_RESOLUTION 0x04
+#endif
+
+#if _MSC_VER <= 1900  // add until VS2015 from processthreadsapi.h
+enum { ProcessPowerThrottling = 4 };
+
+typedef struct _PROCESS_POWER_THROTTLING_STATE {
+    ULONG Version;
+    ULONG ControlMask;
+    ULONG StateMask;
+} PROCESS_POWER_THROTTLING_STATE, * PPROCESS_POWER_THROTTLING_STATE;
+#endif
+
 #if _MSC_VER >= 1400 // valid for VS2005 and later
 #if defined _M_IX86
 #pragma comment(linker,"/manifestdependency:\" \
diff --git a/app/src/main/cpp/core/pngcrc.c b/app/src/main/cpp/core/pngcrc.c
new file mode 100644
index 0000000..9922bc4
--- /dev/null
+++ b/app/src/main/cpp/core/pngcrc.c
@@ -0,0 +1,57 @@
+/*
+ *   pngcrc.c
+ *
+ *   This file is part of Emu48
+ *
+ *   Copyright (C) 2023 Christoph Gießelink
+ *
+ */
+#include "pch.h"
+
+/* CRC polynomial: 0xedb88320 */
+static const unsigned lodepng_crc32_table[256] =
+{
+	0x00000000, 0x77073096, 0xEE0E612C, 0x990951BA, 0x076DC419, 0x706AF48F, 0xE963A535, 0x9E6495A3,
+	0x0EDB8832, 0x79DCB8A4, 0xE0D5E91E, 0x97D2D988, 0x09B64C2B, 0x7EB17CBD, 0xE7B82D07, 0x90BF1D91,
+	0x1DB71064, 0x6AB020F2, 0xF3B97148, 0x84BE41DE, 0x1ADAD47D, 0x6DDDE4EB, 0xF4D4B551, 0x83D385C7,
+	0x136C9856, 0x646BA8C0, 0xFD62F97A, 0x8A65C9EC, 0x14015C4F, 0x63066CD9, 0xFA0F3D63, 0x8D080DF5,
+	0x3B6E20C8, 0x4C69105E, 0xD56041E4, 0xA2677172, 0x3C03E4D1, 0x4B04D447, 0xD20D85FD, 0xA50AB56B,
+	0x35B5A8FA, 0x42B2986C, 0xDBBBC9D6, 0xACBCF940, 0x32D86CE3, 0x45DF5C75, 0xDCD60DCF, 0xABD13D59,
+	0x26D930AC, 0x51DE003A, 0xC8D75180, 0xBFD06116, 0x21B4F4B5, 0x56B3C423, 0xCFBA9599, 0xB8BDA50F,
+	0x2802B89E, 0x5F058808, 0xC60CD9B2, 0xB10BE924, 0x2F6F7C87, 0x58684C11, 0xC1611DAB, 0xB6662D3D,
+	0x76DC4190, 0x01DB7106, 0x98D220BC, 0xEFD5102A, 0x71B18589, 0x06B6B51F, 0x9FBFE4A5, 0xE8B8D433,
+	0x7807C9A2, 0x0F00F934, 0x9609A88E, 0xE10E9818, 0x7F6A0DBB, 0x086D3D2D, 0x91646C97, 0xE6635C01,
+	0x6B6B51F4, 0x1C6C6162, 0x856530D8, 0xF262004E, 0x6C0695ED, 0x1B01A57B, 0x8208F4C1, 0xF50FC457,
+	0x65B0D9C6, 0x12B7E950, 0x8BBEB8EA, 0xFCB9887C, 0x62DD1DDF, 0x15DA2D49, 0x8CD37CF3, 0xFBD44C65,
+	0x4DB26158, 0x3AB551CE, 0xA3BC0074, 0xD4BB30E2, 0x4ADFA541, 0x3DD895D7, 0xA4D1C46D, 0xD3D6F4FB,
+	0x4369E96A, 0x346ED9FC, 0xAD678846, 0xDA60B8D0, 0x44042D73, 0x33031DE5, 0xAA0A4C5F, 0xDD0D7CC9,
+	0x5005713C, 0x270241AA, 0xBE0B1010, 0xC90C2086, 0x5768B525, 0x206F85B3, 0xB966D409, 0xCE61E49F,
+	0x5EDEF90E, 0x29D9C998, 0xB0D09822, 0xC7D7A8B4, 0x59B33D17, 0x2EB40D81, 0xB7BD5C3B, 0xC0BA6CAD,
+	0xEDB88320, 0x9ABFB3B6, 0x03B6E20C, 0x74B1D29A, 0xEAD54739, 0x9DD277AF, 0x04DB2615, 0x73DC1683,
+	0xE3630B12, 0x94643B84, 0x0D6D6A3E, 0x7A6A5AA8, 0xE40ECF0B, 0x9309FF9D, 0x0A00AE27, 0x7D079EB1,
+	0xF00F9344, 0x8708A3D2, 0x1E01F268, 0x6906C2FE, 0xF762575D, 0x806567CB, 0x196C3671, 0x6E6B06E7,
+	0xFED41B76, 0x89D32BE0, 0x10DA7A5A, 0x67DD4ACC, 0xF9B9DF6F, 0x8EBEEFF9, 0x17B7BE43, 0x60B08ED5,
+	0xD6D6A3E8, 0xA1D1937E, 0x38D8C2C4, 0x4FDFF252, 0xD1BB67F1, 0xA6BC5767, 0x3FB506DD, 0x48B2364B,
+	0xD80D2BDA, 0xAF0A1B4C, 0x36034AF6, 0x41047A60, 0xDF60EFC3, 0xA867DF55, 0x316E8EEF, 0x4669BE79,
+	0xCB61B38C, 0xBC66831A, 0x256FD2A0, 0x5268E236, 0xCC0C7795, 0xBB0B4703, 0x220216B9, 0x5505262F,
+	0xC5BA3BBE, 0xB2BD0B28, 0x2BB45A92, 0x5CB36A04, 0xC2D7FFA7, 0xB5D0CF31, 0x2CD99E8B, 0x5BDEAE1D,
+	0x9B64C2B0, 0xEC63F226, 0x756AA39C, 0x026D930A, 0x9C0906A9, 0xEB0E363F, 0x72076785, 0x05005713,
+	0x95BF4A82, 0xE2B87A14, 0x7BB12BAE, 0x0CB61B38, 0x92D28E9B, 0xE5D5BE0D, 0x7CDCEFB7, 0x0BDBDF21,
+	0x86D3D2D4, 0xF1D4E242, 0x68DDB3F8, 0x1FDA836E, 0x81BE16CD, 0xF6B9265B, 0x6FB077E1, 0x18B74777,
+	0x88085AE6, 0xFF0F6A70, 0x66063BCA, 0x11010B5C, 0x8F659EFF, 0xF862AE69, 0x616BFFD3, 0x166CCF45,
+	0xA00AE278, 0xD70DD2EE, 0x4E048354, 0x3903B3C2, 0xA7672661, 0xD06016F7, 0x4969474D, 0x3E6E77DB,
+	0xAED16A4A, 0xD9D65ADC, 0x40DF0B66, 0x37D83BF0, 0xA9BCAE53, 0xDEBB9EC5, 0x47B2CF7F, 0x30B5FFE9,
+	0xBDBDF21C, 0xCABAC28A, 0x53B39330, 0x24B4A3A6, 0xBAD03605, 0xCDD70693, 0x54DE5729, 0x23D967BF,
+	0xB3667A2E, 0xC4614AB8, 0x5D681B02, 0x2A6F2B94, 0xB40BBE37, 0xC30C8EA1, 0x5A05DF1B, 0x2D02EF8D
+};
+
+/*Return the CRC of the bytes buf[0..len-1].*/
+unsigned lodepng_crc32(const unsigned char* data, size_t length)
+{
+	unsigned r = 0xffffffffu;
+	while (length--)
+	{
+		r = lodepng_crc32_table[(r ^ *data++) & 0xffu] ^ (r >> 8u);
+	}
+	return ~r;
+}
diff --git a/app/src/main/cpp/core/romcrc.c b/app/src/main/cpp/core/romcrc.c
new file mode 100644
index 0000000..fd0c172
--- /dev/null
+++ b/app/src/main/cpp/core/romcrc.c
@@ -0,0 +1,250 @@
+/*
+ *   romcrc.c
+ *
+ *   This file is part of Emu48
+ *
+ *   Copyright (C) 2022 Christoph Gießelink
+ *
+ */
+#include "pch.h"
+#include "Emu48.h"
+#include "ops.h"
+
+// flash page types
+#define BOOT	0x86
+#define FS		0x18
+#define SYSTEM	0x32
+#define ROM		0x0F
+#define RAM		0xF0
+
+//################
+//#
+//#    Restore HP38G/HP48GX/SX ROM CRC
+//#
+//################
+
+// Clarke/Yorke CRC for HP38G and HP48GX/SX
+#define a0	0x0								// Start Address
+#define d0	(n0*16)							// Address offset
+#define n0	0x4000							// Reads/Half-Sector
+#define s0	1								// #Sectors (Sector Size=2*d)
+
+// rebuild of the calculator =CHECKSUM function for the Clarke and the Yorke chip ROM
+static WORD Checksum(LPBYTE pbyROM, DWORD dwStart, DWORD dwOffset, INT nReads, INT nSector)
+{
+	int i,j;
+
+	WORD wCrc = 0;
+
+	for (;nSector > 0; --nSector)			// evaluate each sector
+	{
+		LPBYTE pbyAddr1 = pbyROM + dwStart;
+		LPBYTE pbyAddr2 = pbyAddr1 + dwOffset;
+
+		for (i = 0; i < nReads; ++i)		// no. of reads in sector
+		{
+			for (j = 0; j < 16; ++j) wCrc = UpCRC(wCrc,*pbyAddr1++);
+			for (j = 0; j < 16; ++j) wCrc = UpCRC(wCrc,*pbyAddr2++);
+		}
+
+		dwStart += 2 * dwOffset;			// next start page
+	}
+	return wCrc;
+}
+
+// calculate proper checksum to produce final CRC of FFFF
+static __inline WORD CalcChksum(WORD wCrc, WORD wChksum)
+{
+	WORD q, r = wCrc, s = wChksum;
+
+	// first take the last 4-nib back out of the CRC
+	r = (((r >> 12) * 0x811) ^ (r << 4) ^ (s & 0xf));
+	s >>= 4;
+	r = (((r >> 12) * 0x811) ^ (r << 4) ^ (s & 0xf));
+	s >>= 4;
+	r = (((r >> 12) * 0x811) ^ (r << 4) ^ (s & 0xf));
+	s >>= 4;
+	r = (((r >> 12) * 0x811) ^ (r << 4) ^ (s & 0xf));
+
+	// calculate new checksum to correct the CRC
+	s = 0xf831;								// required MSNs to make goal
+	q = (q<<4) | ((r ^ s) & 0xf);			// get 1st (least sig) nib
+	r = (r>>4) ^ ((s & 0xf) * 0x1081);
+	s >>= 4;
+	q = (q<<4) | ((r ^ s) & 0xf);
+	r = (r>>4) ^ ((s & 0xf) * 0x1081);
+	s >>= 4;
+	q = (q<<4) | ((r ^ s) & 0xf);
+	r = (r>>4) ^ ((s & 0xf) * 0x1081);
+	s >>= 4;
+	q = (q<<4) | ((r ^ s) & 0xf);
+	return q;
+}
+
+static VOID CorrectCrc(DWORD dwAddrCrc, WORD wCrc)
+{
+	if (wCrc != 0xFFFF)						// wrong crc result
+	{
+		INT s;
+
+		// get actual crc correction value
+		const WORD wChkAct =   (pbyRom[dwAddrCrc+0] << 12)
+							 | (pbyRom[dwAddrCrc+1] << 8)
+							 | (pbyRom[dwAddrCrc+2] << 4)
+							 | (pbyRom[dwAddrCrc+3]);
+
+		wCrc = CalcChksum(wCrc,wChkAct);	// calculate new checksum
+
+		for (s = 3; s >= 0; --s)			// write new checksum
+		{
+			PatchNibble(dwAddrCrc + s,(BYTE) (wCrc & 0xf));
+			wCrc >>= 4;
+		}
+	}
+	return;
+}
+
+
+//################
+//#
+//#    Restore HP49G ROM CRC
+//#
+//################
+
+static VOID CorrectFlashCrc(LPBYTE pbyMem, DWORD dwSize, DWORD dwOffset, DWORD dwLength)
+{
+	// address overflow (data length + 4 nibble CRC)
+	if (dwOffset + dwLength + 4 <= dwSize)
+	{
+		WORD wRefCrc,wCrc = 0;
+
+		pbyMem += dwOffset;						// start address
+
+		for (; dwLength > 0; --dwLength)		// update CRC
+		{
+			wCrc = UpCRC(wCrc,*pbyMem++);
+		}
+
+		wRefCrc = (WORD) Npack(pbyMem,4);		// read reference CRC
+
+		if(wRefCrc != wCrc)						// wrong page CRC
+		{
+			INT s;
+
+			// linear CRC address in ROM
+			DWORD dwAddrCrc = (DWORD) (pbyMem - pbyRom);
+
+			wRefCrc = wCrc;						// working copy of CRC
+			for (s = 0; s < 4; ++s)				// write new checksum
+			{
+				PatchNibble(dwAddrCrc++,(BYTE) (wRefCrc & 0xf));
+				wRefCrc >>= 4;
+			}
+
+			_ASSERT(wCrc == (WORD) Npack(pbyMem,4));
+		}
+	}
+	return;
+}
+
+static __inline VOID CorrectFlashRom(LPBYTE pbyMem, DWORD dwSize)
+{
+	CorrectFlashCrc(pbyMem,dwSize,0x20A,Npack(pbyMem+0x20A,5));
+	return;
+}
+
+static __inline VOID CorrectFlashSystem(LPBYTE pbyMem, DWORD dwSize)
+{
+	CorrectFlashCrc(pbyMem,dwSize,0x20A,Npack(pbyMem+0x100,5));
+	return;
+}
+
+static __inline VOID CorrectFlashPage(LPBYTE pbyMem, DWORD dwSize, DWORD dwPage)
+{
+	_ASSERT(dwPage >= 0 && dwPage < 16);
+
+	dwPage *= _KB(128);						// convert page no. to data offset
+	if (dwPage + _KB(128) <= dwSize)		// page inside flash chip
+	{
+		BYTE byType;
+
+		pbyMem += dwPage;					// page address
+		dwPage = _KB(128);					// page size
+
+		// get bank type
+		byType = (BYTE) Npack(pbyMem+0x200,2);
+		if (byType == BOOT)					// 1st half of page is the boot bank
+		{
+			pbyMem += _KB(64);				// 2nd half of page
+			dwPage = _KB(64);				// page size
+
+			// get bank type
+			byType = (BYTE) Npack(pbyMem+0x200,2);
+		}
+
+		_ASSERT(dwPage == _KB(64) || dwPage == _KB(128));
+
+		switch (byType)
+		{
+		case FS:  // FRBankFileSystem
+		case ROM: // FRBankRom
+			CorrectFlashRom(pbyMem,dwPage);
+			break;
+		case SYSTEM: // FRBankSystem
+			CorrectFlashSystem(pbyMem,dwPage);
+			break;
+		case RAM: // FRBankRam
+		default: // illegal bank identifier
+			break;
+		}
+	}
+	return;
+}
+
+static __inline VOID CorrectAllFlashPages(VOID)
+{
+	DWORD dwPage;
+
+	// check CRC of all pages
+	CONST DWORD dwLastPage = dwRomSize / _KB(128);
+	for (dwPage = 0; dwPage < dwLastPage; ++dwPage)
+	{
+		// correct CRC of page
+		CorrectFlashPage(pbyRom,dwRomSize,dwPage);
+	}
+	return;
+}
+
+
+//################
+//#
+//#    Restore ROM CRC
+//#
+//################
+
+VOID RebuildRomCrc(VOID)
+{
+	// HP38G, HP48GX, HP48SX
+	if ((strchr("6AGS",cCurrentRomType)) && dwRomSize >= _KB(256))
+	{
+		// first 256KB
+		CorrectCrc(0x7FFFC,Checksum(pbyRom,a0,d0,n0,s0));
+	}
+	// HP38G, HP48GX
+	if ((strchr("6AG",cCurrentRomType)) && dwRomSize == _KB(512))
+	{
+		// second 256KB
+		CorrectCrc(0xFFFFC,Checksum(pbyRom,a0+_KB(256),d0,n0,s0));
+	}
+	// HP39G/40G
+	if (cCurrentRomType == 'E')
+	{
+		// has no Crc
+	}
+	// HP49G
+	if (cCurrentRomType == 'X' && dwRomSize == _KB(2048))
+	{
+		CorrectAllFlashPages();				// go through all pages
+	}
+	return;
+}
diff --git a/app/src/main/cpp/core/serial.c b/app/src/main/cpp/core/serial.c
index 81f59a3..0433a06 100644
--- a/app/src/main/cpp/core/serial.c
+++ b/app/src/main/cpp/core/serial.c
@@ -107,6 +107,8 @@ BOOL CommOpen(LPTSTR strWirePort,LPTSTR strIrPort)
 	_ASSERT(Chipset.IORam[IOC] & SON);		// UART on
 	CommClose();							// close port if already open
 
+	dwBytesRead = 0L;						// no bytes received
+
 	if (lstrcmp(strPort, _T(NO_SERIAL)))	// port defined
 	{
 		TCHAR szDevice[256] = _T("\\\\.\\");
@@ -130,7 +132,6 @@ BOOL CommOpen(LPTSTR strWirePort,LPTSTR strIrPort)
 			DWORD dwThreadId;
 
 			nRp = 0;						// reset receiver state
-			dwBytesRead = 0L;
 
 			SetCommTimeouts(hComm,&CommTimeouts);
 			CommSetBaud();
@@ -157,7 +158,9 @@ BOOL CommOpen(LPTSTR strWirePort,LPTSTR strIrPort)
 			while (!bReading) Sleep(0);		// wait for SerialThread started
 		}
 		else
+		{
 			hComm = NULL;
+		}
 	}
 
 	#if defined DEBUG_SERIAL
@@ -356,12 +359,23 @@ VOID CommReceive(VOID)
 			break;
 
 		// reject reading if com port is closed and not whole operation
-		if (hComm && dwBytesRead == 0L)		// com port open and buffer empty
+		if (hComm)							// com port open
 		{
-			if (ReadFile(hComm,cBuffer,sizeof(cBuffer),&dwBytesRead,&os) == FALSE)
-				dwBytesRead = 0L;
-			else							// bytes received
-				nRp = 0;					// reset read pointer
+			UINT uCnt = 0;					// retry counter
+
+			while (dwBytesRead == 0L)		// buffer empty
+			{
+				if (ReadFile(hComm,cBuffer,sizeof(cBuffer),&dwBytesRead,&os) == FALSE)
+					dwBytesRead = 0L;
+				else						// bytes received
+					nRp = 0;				// reset read pointer
+
+				// something received or passed 1st retry
+				if (dwBytesRead != 0L || ++uCnt > 1)
+					break;					// quit
+
+				Sleep(1);					// workaround, retry 1ms later
+			}
 		}
 
 		if (dwBytesRead == 0L)				// receive buffer empty
diff --git a/app/src/main/cpp/core/udp.c b/app/src/main/cpp/core/udp.c
index e404943..7e20930 100644
--- a/app/src/main/cpp/core/udp.c
+++ b/app/src/main/cpp/core/udp.c
@@ -10,27 +10,27 @@
 #include "Emu48.h"
 
 TCHAR szUdpServer[1024] = _T("localhost");
-WORD  wUdpPort = 5025;						// scpi-raw  
+WORD  wUdpPort = 5025;						// scpi-raw
 
-static IN_ADDR ip_addr = { 255, 255, 255, 255 };
+static SOCKADDR_IN sServer = { AF_INET, 0, { 255, 255, 255, 255 } };
 
 VOID ResetUdp(VOID)
 {
-	ip_addr.s_addr = INADDR_NONE;			// invalidate saved UDP address
+	sServer.sin_addr.s_addr = INADDR_NONE;	// invalidate saved UDP address
 	return;
 }
 
 BOOL SendByteUdp(BYTE byData)
 {
-	WSADATA     wsd;
-	SOCKET      sClient;
-	SOCKADDR_IN sServer;
+	WSADATA wsd;
+	SOCKET  sClient;
 
 	BOOL bErr = TRUE;
 
 	VERIFY(WSAStartup(MAKEWORD(1,1),&wsd) == 0);
 
-	if (ip_addr.s_addr == INADDR_NONE)		// IP address not specified
+	// IP address not specified
+	if (sServer.sin_addr.s_addr == INADDR_NONE)
 	{
 		LPSTR lpszIpAddr;
 
@@ -38,7 +38,7 @@ BOOL SendByteUdp(BYTE byData)
 			DWORD dwLength = lstrlen(szUdpServer) + 1;
 
 			if ((lpszIpAddr = (LPSTR) _alloca(dwLength)) == NULL)
-				return TRUE;				// server not found
+				return TRUE;				// server ip address not found
 
 			WideCharToMultiByte(CP_ACP, WC_COMPOSITECHECK,
 								szUdpServer, dwLength,
@@ -47,27 +47,26 @@ BOOL SendByteUdp(BYTE byData)
 			lpszIpAddr = szUdpServer;
 		#endif
 
-		ip_addr.s_addr = inet_addr(lpszIpAddr);
+		// try to interpret string as IPv4 address
+		sServer.sin_addr.s_addr = inet_addr(lpszIpAddr);
 
 		// not a valid ip address -> try to get ip address from name server
-		if (ip_addr.s_addr == INADDR_NONE)
+		if (sServer.sin_addr.s_addr == INADDR_NONE)
 		{
 			PHOSTENT host = gethostbyname(lpszIpAddr);
 			if (host == NULL)
 			{
-				return TRUE;				// server not found
+				return TRUE;				// server ip address not found
 			}
 
-			ip_addr.s_addr = ((PIN_ADDR) host->h_addr_list[0])->s_addr;
+			sServer.sin_addr.s_addr = ((PIN_ADDR) host->h_addr_list[0])->s_addr;
 		}
 	}
 
 	// create UDP socket
 	if ((sClient = socket(AF_INET, SOCK_DGRAM, 0)) != INVALID_SOCKET)
 	{
-		sServer.sin_family = AF_INET;
 		sServer.sin_port = htons(wUdpPort);
-		sServer.sin_addr.s_addr = ip_addr.s_addr;
 
 		// transmit data byte
 		bErr = sendto(sClient, (LPCCH) &byData, sizeof(byData), 0, (LPSOCKADDR) &sServer, sizeof(sServer)) == SOCKET_ERROR;