diff --git a/src/mame/etc/jalmah.x68 b/src/mame/etc/jalmah.x68
index 9a77df83024..3615bf9bbf8 100644
--- a/src/mame/etc/jalmah.x68
+++ b/src/mame/etc/jalmah.x68
@@ -14,64 +14,61 @@
 START:
     ORG    $0                       ; palette code snippet (test mode & gameplay)
     move.w #$1, $80016.l            ; set priority number (for urashima)
-    move.w #$f, D0
+    move.w #$f, D0                  ; set loop 1
 FetchNewPalette:
-    move.l A0, $100400.l
-    movea.l (A0), A0
-    move.w #$f, D1
-    bsr    UploadPaletteChunk
-    movea.l $100400.l, A0
+    move.l A0, $100400.l            ; save address to our local buffer (address currently points to an index of actual palette to transfer)
+    movea.l (A0), A0                ; read ROM location for the actual palette source
+    move.w #$f, D1                  ; set loop 2 variable
+    bsr    UploadPaletteChunk       ; jump to uploading routine
+    movea.l $100400.l, A0           ; restore address index, increment by next address
     adda.w #$4, A0
     dbra  D0, FetchNewPalette
     rts
 
 UploadPaletteChunk:
-    move.w (A0)+, (A1)+
+    move.w (A0)+, (A1)+             ; copy palette source in ROM to palette RAM
     dbra  D1, UploadPaletteChunk
     rts
 
     ORG    $0800                    ; sound code snippet
-;    move.w #$0, $8001a.l
-;    move.w $f0b80.l, $80018.l
-;    move.w $100ffc.l, $80018.l
-;    move.w $100ffe.l, $8001a.l
-    movem.l D1, -(A7)
-    move.w D0, D1
-    ror.w  #$8, D1
-    and.w  #$f, D1
+    movem.l D1, -(A7)               
+    move.w D0, D1                   ; D0 is raw sound command, low byte is command number, everything else is banking and probably voice channel (unhandled)
+    ror.w  #$8, D1                  
+    and.w  #$f, D1                  ; take D1 as raw banking number
     bsr    CheckSoundZA
     bsr    CheckSoundBank
-    move.w #$8, $80040.l
+    move.w #$8, $80040.l            ; clear channel
     bsr    SoundStatus
-    andi.w #$3f, D0
+    andi.w #$3f, D0                 ; take command number and write it to OKI port
     ori.w  #$80, D0
     move.w D0, $80040.l
     bsr    SoundStatus
-    move.w #$10, $80040.l
+    move.w #$10, $80040.l           ; play channel
     movem.l (A7)+, D1
     rts
 SoundStatus:
-    movem.l D0, -(A7)
+    movem.l D0, -(A7)               
 ReadStatus:
-    move.w $80040.l, D0
+    move.w $80040.l, D0             ; check OKI voice status
     andi.w #$1,D0
     bne  ReadStatus
     movem.l (A7)+, D0
     rts
 ; guess: special bits set in register D0 affect banking (oki can play up to 64 samples so bits 6 and 7 cannot be used)
+; we simulate "ZA" writing but use the other bank register (jalmah can do both, cfr. ports $80018 and $8001a
 CheckSoundZA:
-    btst  #$6, D0 ;urashima BGM at start of game
+    btst  #$6, D0                    ; urashima BGM at start of game
     beq   NoZA1
-    ror.w #$1, D1
+    ror.w #$1, D1                    ; shift one down
     rts
 NoZA1:
-    btst  #$07, D0 ;mjzoomin BGM at start of game
+    btst  #$07, D0                   ; mjzoomin BGM at start of game
     beq   NoZA2
-    move.w #$8, D1
+    move.w #$8, D1                   ; hardcode to bank 3
 NoZA2:
     rts
 CheckSoundBank:
-    cmpi.w #$1, D1
+    cmpi.w #$1, D1                   ; verify our raw D1 and set base bank accordingly
     beq   SetBank0
     cmpi.w #$2, D1
     beq   SetBank1
@@ -91,29 +88,29 @@ SetBank2:
 
     ORG    $1000                    ; tile upload snippet
 TileUploadStart:
-    move.w (A2)+, (A1)+
+    move.w (A2)+, (A1)+             ; just take A2 source (tiles) to A1 destination VRAM
     dbra   D0, TileUploadStart
     rts
 
     ORG    $1800                    ; (another) palette code snippet
     movem.l D0-D7/A1-A6, -(A7)      ; save stack (A0 intentionally updated by this snippet)
-    move.w #$f, D0
+    move.w #$f, D0                  ; what's the difference here? Same as above but no hardcoded priority?
     bsr   FetchNewPalette
     movem.l (A7)+, D0-D7/A1-A6
     rts
 
     ORG    $2000                    ; daireikai RNG snippet (guess)
     move.w D5, $100400.l
-    move.w $f000c.l, D5
-    add.l  D6, D5
+    move.w $f000c.l, D5             ; take current RNG number
+    add.l  D6, D5                   ; add D6
     andi.w #$3f, D5
-    move.w D5, $f000c.l
+    move.w D5, $f000c.l             ; round it
     move.w $100400.l, D5
     rts
     ORG    $2800                    ; daireikai layer clearances
     movem.l D0-D7/A0-A6, -(A7)
-    lea    $90000.l, A6
-    move.w #$1fff, D1
+    lea    $90000.l, A6             ; layer 0
+    move.w #$1fff, D1               
     move.w #$00ff, D0
     bsr    ClearLayer
     movem.l (A7)+, D0-D7/A0-A6
@@ -124,7 +121,7 @@ ClearLayer:
     rts
     ORG    $2880
     movem.l D0-D7/A0-A6, -(A7)
-    lea    $94000.l, A6
+    lea    $94000.l, A6              ; layer 1
     move.w #$1fff, D1
     move.w #$00ff, D0
     bsr ClearLayer
@@ -132,7 +129,7 @@ ClearLayer:
     rts
     ORG    $2900
     movem.l D0-D7/A0-A6, -(A7)
-    lea    $98000.l, A6
+    lea    $98000.l, A6              ; layer 2
     move.w #$1fff, D1
     move.w #$f0ff, D0
     bsr ClearLayer
@@ -143,6 +140,7 @@ ClearLayer:
     dc.w   $ffff
     END START
 
+
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