Prepare README for release

README.md

@@ -1,7 +1,24 @@
 # Emulator of the HP 48GX, HP 49, and HP 40
 
+**This is a fork of saturn v4.1.1.1 originally by Ivan Cibrario Bertolotti.**
+
+Original source are available at https://www.hpcalc.org/details/4382
+
+The GUI has been replaced by a new one (taken from x48ng) in SDL2 and/or ncurses.
+
+The main binary is `dist/saturn` with helpers/wrappers scripts available per model as:
+* `dist/saturn48gx`
+* `dist/saturn48sx`
+* `dist/saturn49g` (not really functional (yet))
+* `dist/saturn40g` (not really functional (yet))
+
 ## Building
 
+Dependencies:
+- SDL2
+- ncursesw
+
+
 ``` shell
 make
 ```
@@ -12,41 +29,9 @@ make install DESTDIR=/
 ```
 
 ## Using
+Use the wrappers scripts.
 
-### locally
+The local data are stored under $XDG_CONFIG_HOME/saturn<model>/
-``` shell
-./dist/saturn48gx
-```
-or
-``` shell
-./dist/saturn48sx
-```
-or
-``` shell
-./dist/saturn49g
-```
-or
-``` shell
-./dist/saturn40g
-```
-
-### when installed
-``` shell
-saturn48gx
-```
-or
-``` shell
-saturn48sx
-```
-or
-``` shell
-saturn49g
-```
-or
-``` shell
-saturn40g
-```
-
 
 ## Post-fork changelog
 - replaced the build system with a basic Makefile
@@ -57,10 +42,3 @@ saturn40g
 
 ## Known bugs
 - I could get neither the 49 nor the 40 ROM running yet.
-
-
-**This is a fork of saturn v4.1.1.1 originally by Ivan Cibrario Bertolotti.**
-
-Original source are available at https://www.hpcalc.org/details/4382
-
-Original documentation are kept in ./docs-4.1.1.1/ and ./manual/