updated sid tune

new sid tune is bigger than 4k, so charset had to be moved
now (part of) first half of the charset actually is used by the sid
and ignored by the VIC; chars had to be redefined

README.md

@@ -68,9 +68,10 @@ Address               | PRG   | Description
 #### Custom charset
 Index           | Description
 ----------------|-------------
-```$00 - $1F``` |   A-Z (space first)
-```$20 - $3F``` |   A-Z, reversed (space first)
-```$40 - $4F``` |   hex digits
-```$50 - $5F``` |   hex digits, reversed
-```$60 -    ``` |   game tiles
+```$00 - $7F``` |   unused (space for SID)
+```$80 - $9F``` |   A-Z (space first)
+```$A0 - $BF``` |   A-Z, reversed (space first)
+```$C0 - $CF``` |   hex digits
+```$D0 - $DF``` |   hex digits, reversed
+```$E0 -    ``` |   game tiles
 

src/initdata.asm

@@ -38,10 +38,10 @@ SCREEN_H    =   24
 
 ; Tiles
 ; -----
-EMPTY_TILE  =   $60
-SNAKE_TILE  =   $61
-FOOD_TILE   =   $62
-WALL_TILE   =   $63
+EMPTY_TILE  =   $e0
+SNAKE_TILE  =   $e1
+FOOD_TILE   =   $e2
+WALL_TILE   =   $e3
 
 ; Tiles colors
 ; Note: these colors will be picked by the level select routine

src/levels.asm

@@ -60,7 +60,7 @@ statusLevelLoad SUBROUTINE
     ; Upper bar -- fill with spaces, color yellow
     ldx #39
 .loop:
-    lda #$0
+    lda #$80
     sta $400,x
     lda #7
     sta $d800,x
@@ -139,9 +139,9 @@ writeLevelElement:
     lda levelT
     sta (levelVideoPointer),y
         ; tiles colors can be found in an array
-        ; position in array = tile value - $60
+        ; position in array = tile value - $e0
     sec
-    sbc #$60
+    sbc #$e0
     tax
     lda tilesColors,x
     sta (levelColorPointer),y

src/main.asm

@@ -25,15 +25,16 @@
     SEG sidSegment
     org $1000
 sidtune:
-    INCBIN "../res.bin/amour.sid"
+    INCBIN "../res.bin/amour2.sid"
 #if VERBOSE = 1
-    ECHO "End of SIDtune at ",.,"Space left:",($2000 - .)
+    ECHO "top $2000: End of SIDtune at ",.,"Space left:",($2000 - .)
+    ECHO "top $2400: End of SIDtune at ",.,"Space left:",($2400 - .)
 #endif
 
 ; Font Data
 ; ----------------------------------------------------------------------
     SEG fontSegment
-    org $2000
+    org $2400
 ; This binary data that defines the font is exactly 2kB long ($800)
     INCLUDE "font.asm"
 

src/program.asm

@@ -166,10 +166,10 @@ checkEndStatus:
 
     ; Play music
     jsr sidtune + 3
-    jsr sidtune + 3
-    jsr sidtune + 3
-    jsr sidtune + 3
-    jsr sidtune + 3
+;    jsr sidtune + 3
+;    jsr sidtune + 3
+;    jsr sidtune + 3
+;    jsr sidtune + 3
 
     ; Increase random value
     inc random

src/subroutines.asm

@@ -9,7 +9,7 @@ LASTINIT SET .
 clearScreen SUBROUTINE
     ldx #$ff
 .loop:
-    lda #$00
+    lda #$80
     sta $400,x
     sta $500,x
     sta $600,x
@@ -81,12 +81,12 @@ printByte SUBROUTINE
     lsr
     lsr
     lsr
-    ora #$40        ; add 64 (see font)
+    ora #$c0        ; add 192 (see font)
     sta $400,y      ; print msb char
 
     txa             ; Take least significant nibble (use previous copy)
     and #$0f
-    ora #$40        ; add 64 (see font)
+    ora #$c0        ; add 192 (see font)
     sta $401,y      ; print lsb char
 
     rts
@@ -104,22 +104,22 @@ printString SUBROUTINE
     beq .end                    ; if zero, then end (string must be null-terminated)
     cmp #$20                    ; is space?
     bne .checkP1
-    lda #$0
+    lda #$80
     jmp .print
 .checkP1:
     cmp #$28                    ; is char '(' ?
     bne .checkP2
-    lda #$1b
+    lda #$9b
     jmp .print
 .checkP2:
     cmp #$29                    ; is char ')' ?
     bne .checkP3
-    lda #$1c
+    lda #$9c
     jmp .print
 .checkP3
     cmp #$2e                    ; is char '.' ?
     bne .checkNumber
-    lda #$1d
+    lda #$9d
     jmp .print
 .checkNumber:                   ; is char a number?
     cmp #$2f
@@ -129,14 +129,14 @@ printString SUBROUTINE
     sec
     sbc #$30
     clc
-    adc #$40
+    adc #$c0
     jmp .print
 .nextCheck:
 
 .isLetter:
     ; defaults to an uppercase letter of ASCII set
-    sec
-    sbc #$40
+    clc
+    adc #$40
 .print:
     sta (dstScreenPointer),y    ; put screen code to screen
     iny                         ; next char in string

util/rlevel.cpp

@@ -7,11 +7,11 @@ void flush(char last, int count) {
     char tile, color;
     switch(last) {
         case 'x':
-            tile = (char)0x63; break;
+            tile = (char)0xe3; break;
         case 'f':
-            tile = (char)0x62; break;
+            tile = (char)0xe2; break;
         default:
-            tile = (char)0x60; break;
+            tile = (char)0xe0; break;
     }
     cout << tile << (char)count;
 }