Mallard Games Posted July 28, 2019 Share Posted July 28, 2019 Hi, Quick question, right now I have a 8k game using the standard F8 bankswitching scheme. Say I wanted to upgrade it to a 16k game via F6, how would I go about doing that? Do I just add the extra needed banks or is there a more precise procedure required? Quote Link to comment Share on other sites More sharing options...
easmith Posted July 28, 2019 Share Posted July 28, 2019 This should work as a template . I am sure there are other routines that are better but this works. *************************************************************** processor 6502 include "vcs.h" include "macro.h" seg.u Variables org $80 seg Code org $1000 CLEAN_START sei cld ldx #0 txa tay .CLEAR_STACK dex txs pha bne .CLEAR_STACK ; SP=$FF, X = A = Y = 0 Initialize ; initialize variables NextFrame ; start new frame sta WSYNC lda #2 ; start vsync sta VSYNC sta WSYNC sta WSYNC sta WSYNC ldx #49 stx TIM64T lda #0 ; end vsync sta VSYNC sta HMCLR VBLANKLOGIC ENDVBLANK sta WSYNC lda INTIM bne VertBlankreal lda #0 sta VBLANK KERNEL OverScan ;start Overscan lda #2 sta VBLANK lda #32 sta TIM64T OVERSCANLOGIC jsr CallBank2Subroutine jsr CallBank3Subroutine jsr CallBank4Subroutine OSwait lda INTIM bne OSwait ; check for end of overscan sta CXCLR jmp NextFrame org $1FC0 CallBank2Subroutine ldx $1FF7 ; switch to bank 2 nop ; 1FE3 jsr Bank2Subroutine nop ; . nop ; . nop ; 1FE6 lda $1FF8 (Switch back to bank 1) nop ; . nop ; . rts org $1FD0 CallBank3Subroutine ldx $1FF8 ; switch to bank 2 nop ; 1FE3 jsr Bank2Subroutine nop ; . nop ; . nop ; 1FE6 lda $1FF8 (Switch back to bank 1) nop ; . nop ; . rts org $1FE0 CallBank4Subroutine ldx $1FF9 ; switch to bank 2 nop ; 1FE3 jsr Bank2Subroutine nop ; . nop ; . nop ; 1FE6 lda $1FF8 (Switch back to bank 1) nop ; . nop ; . rts reset ORG $1FF4 JMP CLEAN_START .byte 0,0,0,0,0 .word $1FF4 .word 0 ;bank2 org $2000 rorg $1000 BANK2Graphics bank2logicHERE rts org $2FC3 rorg $1FC3 jsr bank2logic ldx $1FF6 ORG $2FF4 RORG $1FF4 JMP CLEAN_START .byte 0,0,0,0,0 .word $1FF4 .word 0 ; endbank2 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ;bank3 org $3000 rorg $1000 Bank3Graphics bank3logicHERE rts org $3FD3 rorg $1FD3 jsr bank3logic ldx $1FF6 ORG $3FF4 RORG $1FF4 JMP CLEAN_START .byte 0,0,0,0,0 .word $1FF4 .word 0 ; endbank3 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ;;;Bank4 org $4000 rorg $1000 Bank4Graphics Bank4logicHERE rts org $4fE3 rorg $1fE3 jsr Bank4logic ldx $1FF6 ORG $4FF4 RORG $1FF4 JMP CLEAN_START .byte 0,0,0,0,0 .word $1FF4 .word 0 Quote Link to comment Share on other sites More sharing options...
Mallard Games Posted July 29, 2019 Author Share Posted July 29, 2019 12 hours ago, easmith said: This should work as a template . I am sure there are other routines that are better but this works. *************************************************************** processor 6502 include "vcs.h" include "macro.h" seg.u Variables org $80 seg Code org $1000 CLEAN_START sei cld ldx #0 txa tay .CLEAR_STACK dex txs pha bne .CLEAR_STACK ; SP=$FF, X = A = Y = 0 Initialize ; initialize variables NextFrame ; start new frame sta WSYNC lda #2 ; start vsync sta VSYNC sta WSYNC sta WSYNC sta WSYNC ldx #49 stx TIM64T lda #0 ; end vsync sta VSYNC sta HMCLR VBLANKLOGIC ENDVBLANK sta WSYNC lda INTIM bne VertBlankreal lda #0 sta VBLANK KERNEL OverScan ;start Overscan lda #2 sta VBLANK lda #32 sta TIM64T OVERSCANLOGIC jsr CallBank2Subroutine jsr CallBank3Subroutine jsr CallBank4Subroutine OSwait lda INTIM bne OSwait ; check for end of overscan sta CXCLR jmp NextFrame org $1FC0 CallBank2Subroutine ldx $1FF7 ; switch to bank 2 nop ; 1FE3 jsr Bank2Subroutine nop ; . nop ; . nop ; 1FE6 lda $1FF8 (Switch back to bank 1) nop ; . nop ; . rts org $1FD0 CallBank3Subroutine ldx $1FF8 ; switch to bank 2 nop ; 1FE3 jsr Bank2Subroutine nop ; . nop ; . nop ; 1FE6 lda $1FF8 (Switch back to bank 1) nop ; . nop ; . rts org $1FE0 CallBank4Subroutine ldx $1FF9 ; switch to bank 2 nop ; 1FE3 jsr Bank2Subroutine nop ; . nop ; . nop ; 1FE6 lda $1FF8 (Switch back to bank 1) nop ; . nop ; . rts reset ORG $1FF4 JMP CLEAN_START .byte 0,0,0,0,0 .word $1FF4 .word 0 ;bank2 org $2000 rorg $1000 BANK2Graphics bank2logicHERE rts org $2FC3 rorg $1FC3 jsr bank2logic ldx $1FF6 ORG $2FF4 RORG $1FF4 JMP CLEAN_START .byte 0,0,0,0,0 .word $1FF4 .word 0 ; endbank2 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ;bank3 org $3000 rorg $1000 Bank3Graphics bank3logicHERE rts org $3FD3 rorg $1FD3 jsr bank3logic ldx $1FF6 ORG $3FF4 RORG $1FF4 JMP CLEAN_START .byte 0,0,0,0,0 .word $1FF4 .word 0 ; endbank3 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ;;;Bank4 org $4000 rorg $1000 Bank4Graphics Bank4logicHERE rts org $4fE3 rorg $1fE3 jsr Bank4logic ldx $1FF6 ORG $4FF4 RORG $1FF4 JMP CLEAN_START .byte 0,0,0,0,0 .word $1FF4 .word 0 It's not working for me, it gives me the error: Quote line 1102 source.asm Origin Reverse-indexed Source: https://www.dropbox.com/s/uifsayrasmyh5h3/source.asm?dl=1 Quote Link to comment Share on other sites More sharing options...
easmith Posted July 29, 2019 Share Posted July 29, 2019 well it looks like you are following a completely different scheme from what I suggested, but my guess on the error is that your bank 2 code is just too long and taking up too much space in one of the segments ( possibly the last segment before your rorg $1FF4) Quote Link to comment Share on other sites More sharing options...
Mallard Games Posted July 29, 2019 Author Share Posted July 29, 2019 25 minutes ago, easmith said: well it looks like you are following a completely different scheme from what I suggested, but my guess on the error is that your bank 2 code is just too long and taking up too much space in one of the segments ( possibly the last segment before your rorg $1FF4) Actually the only thing difference between your scheme and mine is the way I define the vectors compared to yours. Other that that the org, rorg memory locations are all largely the same. Quote Link to comment Share on other sites More sharing options...
Nukey Shay Posted July 29, 2019 Share Posted July 29, 2019 System vectors are in the wrong locations. EXAMPLE: 132 1ff4 org $1FF4 133 1ff4 ff ff .word.w $FFFF 134 1ff6 135 1ff6 ; *********************************************************************************** 136 1ff6 ; Bank 0 Interrupt Vectors 137 1ff6 ; *********************************************************************************** 138 1ff6 03 10 .word.w ResetBank0 ; NMI 139 1ff8 03 10 .word.w ResetBank0 ; RESET 140 1ffa 03 10 .word.w ResetBank0 ; IRQ NMI should be at $1FFA RESET should be at $1FFC IRQ should be at $1FFE And the game is never going to work correctly if you insist on calling GFX data from a different bank than the subroutine that reads them (explained in the previous thread). Tip: if you have Dasm build a list for you, this will reveal exactly precisely where stumbling occurs. Dasm source.asm -f3 -oduckgame.bin -lreport.txt ORG and RORG are using each other's addresses near the end of the third bank. 1100 3461 .rorg $3FF4 1101 1ff4 org $1FF4 C:\source.asm (1102): error: Origin Reverse-indexed. Aborting assembly Quote Link to comment Share on other sites More sharing options...
Mallard Games Posted August 1, 2019 Author Share Posted August 1, 2019 On 7/29/2019 at 7:12 AM, Nukey Shay said: System vectors are in the wrong locations. EXAMPLE: 132 1ff4 org $1FF4 133 1ff4 ff ff .word.w $FFFF 134 1ff6 135 1ff6 ; *********************************************************************************** 136 1ff6 ; Bank 0 Interrupt Vectors 137 1ff6 ; *********************************************************************************** 138 1ff6 03 10 .word.w ResetBank0 ; NMI 139 1ff8 03 10 .word.w ResetBank0 ; RESET 140 1ffa 03 10 .word.w ResetBank0 ; IRQ NMI should be at $1FFA RESET should be at $1FFC IRQ should be at $1FFE And the game is never going to work correctly if you insist on calling GFX data from a different bank than the subroutine that reads them (explained in the previous thread). Tip: if you have Dasm build a list for you, this will reveal exactly precisely where stumbling occurs. Dasm source.asm -f3 -oduckgame.bin -lreport.txt ORG and RORG are using each other's addresses near the end of the third bank. 1100 3461 .rorg $3FF4 1101 1ff4 org $1FF4 C:\source.asm (1102): error: Origin Reverse-indexed. Aborting assembly Fixed the origin being reverse indexed and the draw score routine being in the wrong bank. Now i'm greeted with a purple screen and nothing else. Scanlines are way off at 350, but that can't be right cause I've comment out the draw score routine in it's proper bank. Source: https://www.dropbox.com/s/uvbmq07rqallmtg/source.asm?dl=1 Binary: https://www.dropbox.com/s/treunfvfc0pdtl6/duckgame.bin?dl=1 Listing: https://www.dropbox.com/s/opvq2p7ag8i0v2u/duckgame.txt?dl=1 Quote Link to comment Share on other sites More sharing options...
Nukey Shay Posted August 2, 2019 Share Posted August 2, 2019 After you store Random, where to next? The program is executing empty Rom. Quote Link to comment Share on other sites More sharing options...
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