diff options
Diffstat (limited to 'bank7.s')
| -rw-r--r-- | bank7.s | 88 |
1 files changed, 70 insertions, 18 deletions
@@ -1,31 +1,57 @@ +; bank 7 of the cartridge image, to be built with -t none. +; this bank is the fixed bank, always mapped at $a000-$bfff, in +; the "left cartridge" area. + + .macpack atari ; for scrcode (screen code) macro + .include "atari.inc" -font = $9c00 -CCNTL = $d500 +; zero page temporaries destptr = FR0 srcptr = FR1 + +; where the romable_taimain code was org'ed. codedest = $0400 +; address of the font, which lives in bank 3 of the cart. +font = $9c00 + +; cc65's atari.inc fails to define this standard Atari label. +CCNTL = $d500 + +; cart_trailer is my name for what the OS calls CARTLOC. +; cc65's atari.inc doesn't define it either. cart_trailer = $bffa + .org $a000 ; left cartridge screendata: + ; uncompressed title screen bitmap, $1700 bytes .incbin "titledata.dat" .res $44, $ff ; fudge factor, keep the DL from crossing a 1K boundary + + ; newtitle.s is the display list and menu code. CART_TARGET is used + ; for conditional assembly (to make it work from ROM). CART_TARGET = 1 .include "newtitle.s" -; copy 7680 bytes from $8000-$9dff to (destptr). -; on exit, destptr points to the next 7680 byte chunk. -copy_30_pages: +; copy_31_pages: +; copy 7936 bytes from $8000-$9dff to (destptr). +; on exit, destptr points to the next 7936 byte chunk. + +; copy_x_pages: +; as above, but accepts number of pages to copy in X register. + +copy_31_pages: + ldx #$1f +copy_x_pages: lda #$0 tay sta srcptr lda #$80 sta srcptr+1 - ldx #$1e @copypage: lda (srcptr),y sta (destptr),y @@ -38,7 +64,27 @@ copy_30_pages: init: rts +mem_msg: + scrcode "Sorry, this game requires at least 32K" +mem_msg_len = * - mem_msg - 1 + +memory_error: + lda #$20 ; red BG + sta COLOR2 + ldy #mem_msg_len +@mloop: + lda mem_msg,y + sta (SAVMSC),y + dey + bpl @mloop +@hang: + bmi @hang + cartstart: + lda RAMTOP + cmp #$80 + bne memory_error + ; turn off ANTIC DMA to speed up copying to RAM lda #0 sta SDMCTL @@ -51,35 +97,41 @@ cartstart: sta destptr+1 lda #0 ; bank 0... sta CCNTL ; ...select it - jsr copy_30_pages + jsr copy_31_pages lda #1 ; bank 1... sta CCNTL ; ...select it - jsr copy_30_pages + jsr copy_31_pages lda #2 ; bank 2... sta CCNTL ; ...select it - jsr copy_30_pages + jsr copy_31_pages lda #3 ; bank 3... sta CCNTL ; ...select it - jsr copy_30_pages + ldx #(>BANK3SIZE)+1 ; BANK3SIZE defined on the command line + jsr copy_x_pages + + .out .sprintf("BANK3SIZE %x (%x pages)", BANK3SIZE, (>BANK3SIZE)+1) ; leave bank 3 enabled, as it has our custom font in it -; set up display list - ;lda #34 - ;sta SDMCTL - ;lda #>font - ;sta CHBAS lda #1 - sta COLDST ; System Reset = reboot - jsr start ; from newtitle.s - jsr $0400 ; run the game (romable_taimain) + sta COLDST ; System Reset = reboot + jsr start ; 'start' is from newtitle.s + jsr codedest ; run the game (romable_taimain) jmp cartstart ; redisplay title screen if "play again? N" .if * > cart_trailer .fatal "bank7 code too large" + .else + .out .sprintf("=> %d bytes free in bank 7", cart_trailer - *) .endif + ; fill with 1 bits until the cart trailer .res cart_trailer - *, $ff + + ; trailer (some docs called it a 'header' but, eh, it doesn't come at + ; the head of the cart...) + ; see Mapping the Atari's entry for 'Cartridge B' or the Tech Ref Manual + ; for a description of this. .word cartstart ; entry point .byte 0 ; 0 = cartridge present .byte 4 ; init and run the cart, don't boot the disk, non-diagnostic |