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Use correct VRAM transfer mode for savestates #203

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8 changes: 4 additions & 4 deletions src/save.asm
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Original file line number Diff line number Diff line change
Expand Up @@ -234,17 +234,17 @@ save_write_table:
dw $1000|$420B, $02 ; Trigger DMA on channel 1
; Address pair, B bus -> A bus. B address = VRAM read ($2139).
dw $0000|$4310, $3981 ; direction = B->A, word reg, B addr = $2139
dw $1000|$2115, $0000 ; VRAM address increment mode.
dw $1000|$2115, $0080 ; VRAM address increment mode.
; Copy VRAM 0000-7FFF to SRAM 750000-757FFF.
dw $0000|$2116, $0000 ; VRAM address >> 1.
dw $9000|$2139, $0000 ; VRAM dummy read.
dw $9000|$213A, $0000 ; VRAM dummy read.
dw $0000|$4312, $0000 ; A addr = $xx0000
dw $0000|$4314, $0075 ; A addr = $75xxxx, size = $xx00
dw $0000|$4316, $0080 ; size = $80xx ($0000), unused bank reg = $00.
dw $1000|$420B, $02 ; Trigger DMA on channel 1
; Copy VRAM 8000-7FFF to SRAM 760000-767FFF.
dw $0000|$2116, $4000 ; VRAM address >> 1.
dw $9000|$2139, $0000 ; VRAM dummy read.
dw $9000|$213A, $0000 ; VRAM dummy read.
dw $0000|$4312, $0000 ; A addr = $xx0000
dw $0000|$4314, $0076 ; A addr = $76xxxx, size = $xx00
dw $0000|$4316, $0080 ; size = $80xx ($0000), unused bank reg = $00.
Expand Down Expand Up @@ -326,7 +326,7 @@ load_write_table:
dw $1000|$420B, $02 ; Trigger DMA on channel 1
; Address pair, A bus -> B bus. B address = VRAM write ($2118).
dw $0000|$4310, $1801 ; direction = A->B, B addr = $2118
dw $1000|$2115, $0000 ; VRAM address increment mode.
dw $1000|$2115, $0080 ; VRAM address increment mode.
; Copy SRAM 750000-757FFF to VRAM 0000-7FFF.
dw $0000|$2116, $0000 ; VRAM address >> 1.
dw $0000|$4312, $0000 ; A addr = $xx0000
Expand Down
6 changes: 3 additions & 3 deletions src/tinystates.asm
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Expand Up @@ -264,7 +264,7 @@ endmacro

macro vram_to_sram(vram_addr, size, sram_addr)
dw $0000|$2116, <vram_addr>&$FFFF ; VRAM address >> 1.
dw $9000|$2139, $0000 ; VRAM dummy read.
dw $9000|$213A, $0000 ; VRAM dummy read.
dw $0000|$4312, <sram_addr>&$FFFF ; A addr = $xx0000
dw $0000|$4314, ((<sram_addr>>>16)&$FF)|((<size>&$FF)<<8) ; A addr = $75xxxx, size = $xx00
dw $0000|$4316, (<size>>>8)&$FF ; size = $80xx ($0000), unused bank reg = $00.
Expand Down Expand Up @@ -292,7 +292,7 @@ save_write_table:

; Address pair, B bus -> A bus. B address = VRAM read ($2139).
dw $0000|$4310, $3981 ; direction = B->A, word reg, B addr = $2139
dw $1000|$2115, $0000 ; VRAM address increment mode.
dw $1000|$2115, $0080 ; VRAM address increment mode.

; Copy VRAM segments
%vram_to_sram($3E00, $400, $726C00)
Expand Down Expand Up @@ -380,7 +380,7 @@ load_write_table:

; Address pair, A bus -> B bus. B address = VRAM write ($2118).
dw $0000|$4310, $1801 ; direction = A->B, B addr = $2118
dw $1000|$2115, $0000 ; VRAM address increment mode.
dw $1000|$2115, $0080 ; VRAM address increment mode.

; Copy VRAM segments, uses $724C00-$735000
%sram_to_vram($3E00, $400, $726C00)
Expand Down