fancy_lores: use the shared vapor lock code
This commit is contained in:
Vince Weaver
parent
914b52eb56
commit
2ce16eaf2c
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@ -0,0 +1,25 @@
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; From http://6502org.wikidot.com/software-delay
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; 25+A cycles (including JSR), 19 bytes (excluding JSR)
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;
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; The branches must not cross page boundaries!
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;
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; Cycles Accumulator Carry flag
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; 0 1 2 3 4 5 6 (hex) 0 1 2 3 4 5 6
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; jsr delay_a ; 6 6 6 6 6 6 6 00 01 02 03 04 05 06
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dly0: sbc #7
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delay_a:cmp #7 ; 2 2 2 2 2 2 2 00 01 02 03 04 05 06 0 0 0 0 0 0 0
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bcs dly0 ; 2 2 2 2 2 2 2 00 01 02 03 04 05 06 0 0 0 0 0 0 0
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lsr ; 2 2 2 2 2 2 2 00 00 01 01 02 02 03 0 1 0 1 0 1 0
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bcs dly1 ; 2 3 2 3 2 3 2 00 00 01 01 02 02 03 0 1 0 1 0 1 0
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dly1: beq dly2 ; 3 3 2 2 2 2 2 00 00 01 01 02 02 03 0 1 0 1 0 1 0
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lsr ; 2 2 2 2 2 00 00 01 01 01 1 1 0 0 1
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beq dly3 ; 3 3 2 2 2 00 00 01 01 01 1 1 0 0 1
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bcc dly3 ; 3 3 2 01 01 01 0 0 1
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dly2: bne dly3 ; 2 2 3 00 00 01 0 1 0
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dly3: rts ; 6 6 6 6 6 6 6 00 00 00 00 01 01 01 0 1 1 1 0 0 1
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;
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; Total cycles: 25 26 27 28 29 30 31
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@ -134,82 +134,34 @@ in_range:
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; setup graphics for vapor lock
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;==============================
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; Clear Page0
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lda #$0
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sta DRAW_PAGE
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lda #$44
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jsr clear_gr
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jsr vapor_lock
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; Make screen half green
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lda #$11
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ldy #24
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jsr clear_page_loop
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; vapor lock returns with us at beginning of hsync in line
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; 114 (7410 cycles), so with 5070 lines to go
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; GR part
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bit LORES ; 4
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bit SET_GR ; 4
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bit FULLGR ; 4
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;=====================================================
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; attempt vapor lock
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; by reading the "floating bus" we can see most recently
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; written value of the display
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; we look for $55 (which is the grey line)
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;=====================================================
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; See:
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; Have an Apple Split by Bob Bishop
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; Softalk, October 1982
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jsr gr_copy_to_current ; 6+ 9292
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; Challenges: each scan line scans 40 bytes.
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; The blanking happens at the *beginning*
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; So 65 bytes are scanned, starting at adress of the line - 25
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; now we have 322 left
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; the scan takes 8 cycles, look for 4 repeats of the value
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; to avoid false positive found if the horiz blanking is mirroring
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; the line (max 3 repeats in that case)
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; 322 - 12 = 310
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; - 3 for jmp
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; 307
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vapor_lock_loop: ; first make sure we have all zeroes
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LDA #$11
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zxloop:
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LDX #$04
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wiloop:
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CMP $C051
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BNE zxloop
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DEX
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BNE wiloop
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; Try X=9 Y=6 cycles=307
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LDA #$44 ; now look for our border color (4 times)
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zloop:
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LDX #$04
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qloop:
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CMP $C051
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BNE zloop
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DEX
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BNE qloop
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ldy #6 ; 2
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loopA: ldx #9 ; 2
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loopB: dex ; 2
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bne loopB ; 2nt/3
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dey ; 2
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bne loopA ; 2nt/3
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; found first line of black after green, at up to line 26 on screen
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; so we want roughly 22 lines * 4 = 88*65 = 5720 + 4550 = 10270
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; - 65 (for the scanline we missed) = 10205 - 12 = 10193
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jsr gr_copy_to_current ; 6+ 9292
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; 10193 - 9298 = 895
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; Fudge factor (unknown) -30 = 865
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; GR part
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bit LORES ; 4
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bit SET_GR ; 4
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bit FULLGR ; 4
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; Try X=88 Y=2 cycles=893 R2
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nop
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ldy #2 ; 2
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loopA:
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ldx #88 ; 2
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loopB:
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dex ; 2
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bne loopB ; 2nt/3
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dey ; 2
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bne loopA ; 2nt/3
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jmp display_loop
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jmp display_loop ; 3
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.align $100
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@ -342,6 +294,8 @@ gr_offsets:
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.include "../asm_routines/gr_unrle.s"
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.include "../asm_routines/keypress.s"
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.include "gr_copy.s"
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.include "delay_a.s"
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.include "vapor_lock.s"
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pictures:
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.word apple_low,apple_high
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@ -135,82 +135,34 @@ in_range:
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; setup graphics for vapor lock
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;==============================
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; Clear Page0
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lda #$0
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sta DRAW_PAGE
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lda #$44
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jsr clear_gr
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jsr vapor_lock ; 6+
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; Make screen half green
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lda #$11
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ldy #24
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jsr clear_page_loop
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;=====================================================
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; attempt vapor lock
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; by reading the "floating bus" we can see most recently
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; written value of the display
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; we look for $55 (which is the grey line)
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;=====================================================
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; See:
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; Have an Apple Split by Bob Bishop
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; Softalk, October 1982
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; Challenges: each scan line scans 40 bytes.
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; The blanking happens at the *beginning*
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; So 65 bytes are scanned, starting at adress of the line - 25
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; the scan takes 8 cycles, look for 4 repeats of the value
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; to avoid false positive found if the horiz blanking is mirroring
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; the line (max 3 repeats in that case)
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vapor_lock_loop: ; first make sure we have all zeroes
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LDA #$11
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zxloop:
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LDX #$04
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wiloop:
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CMP $C051
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BNE zxloop
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DEX
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BNE wiloop
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LDA #$44 ; now look for our border color (4 times)
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zloop:
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LDX #$04
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qloop:
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CMP $C051
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BNE zloop
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DEX
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BNE qloop
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; found first line of black after green, at up to line 26 on screen
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; so we want roughly 22 lines * 4 = 88*65 = 5720 + 4550 = 10270
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; - 65 (for the scanline we missed) = 10205 - 12 = 10193
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jsr gr_copy_to_current ; 6+ 9292
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; 10193 - 9298 = 895
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; Fudge factor (unknown) -30 = 865
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; vapor lock returns with us at beginning of hsync in line
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; 114 (7410 cycles), so with 5070 lines to go
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; GR part
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bit LORES ; 4
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bit SET_GR ; 4
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bit FULLGR ; 4
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; Try X=88 Y=2 cycles=893 R2
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jsr gr_copy_to_current ; 6+ 9292
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nop
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ldy #2 ; 2
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loopA:
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ldx #88 ; 2
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loopB:
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dex ; 2
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bne loopB ; 2nt/3
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; now we have 322 left
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dey ; 2
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bne loopA ; 2nt/3
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; 322 - 12 = 310
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; - 3 for jmp
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; 307
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; Try X=9 Y=6 cycles=307
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ldy #6 ; 2
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loopA: ldx #9 ; 2
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loopB: dex ; 2
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bne loopB ; 2nt/3
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dey ; 2
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bne loopA ; 2nt/3
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jmp display_loop ; 3
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jmp display_loop
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.align $100
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@ -342,6 +294,8 @@ gr_offsets:
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.include "../asm_routines/gr_unrle.s"
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.include "../asm_routines/keypress.s"
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.include "gr_copy.s"
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.include "vapor_lock.s"
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.include "delay_a.s"
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pictures:
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.word apple_low,apple_high
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@ -0,0 +1,238 @@
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; This took a while to track down
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; On Apple II/II+ the horiz blanking addr are $1000 higher than on IIe
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; So on II+ were outside video area, so unlikely to be our set value
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; (unless I foolishly use $ff which some uninitialized mem is set to)
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; Lots of this color fiddling is to make sure you don't accidentally
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; get runs of colors on IIe due to the horiz blank
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; 0-5 aqua 6-12 = grey, 13 - 20 = yellow, 21-23 = aqua rainbow 14
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;
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;
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;16 0 YA
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;17 1 YA
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;18 2 YA
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;19 3 YA
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;20 4 YA
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;21 5 AA
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;22 6 AG
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;23 7 AG
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;0 8 AG
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;1 9 AG
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;2 10 AG
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;3 11 AG
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;4 12 AG
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;5 13 AY ****
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;6 14 GY RAINBOW
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;7 15 GY
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;8 16 GY
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;9 17 GY
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;10 18 GY
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;11 19 GY
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;12 20 GY
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;13 21 YA
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;14 22 YA
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;15 23 YA
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;==============================
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; setup graphics for vapor lock
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;==============================
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vapor_lock:
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; Clear Page0
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lda #$0
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sta DRAW_PAGE
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lda #$ee ; full screen white $ff
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jsr clear_gr
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lda #$dd
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ldy #40
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jsr clear_page_loop ; make bottom half yellow $dd
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lda #$aa
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ldy #24
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jsr clear_page_loop ; make middle grey2 $aa
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lda #$ee
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ldy #10
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jsr clear_page_loop ; make top half aqua $ee
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; set up a rainbow to aid in exact lock
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ldy #00
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rainbow_loop:
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tya
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sta $728+20,Y
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iny
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cpy #20
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bne rainbow_loop
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;btt:
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; jmp btt
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;=====================================================
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; attempt vapor lock
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; by reading the "floating bus" we can see most recently
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; written value of the display
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;=====================================================
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; See:
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; Have an Apple Split by Bob Bishop
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; Softalk, October 1982
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; Challenges: each scan line scans 40 bytes.
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; The blanking happens at the *beginning*
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; So 65 bytes are scanned, starting at adress of the line - 25
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; the scan takes 8 cycles, look for 4 repeats of the value
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; to avoid false positive found if the horiz blanking is mirroring
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; the line (max 3 repeats in that case)
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vapor_lock_loop:
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; first make sure we have a full line of $aa
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lda #$aa ; 2
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zxloop:
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ldx #$04 ; 2
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wiloop:
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cmp $C051 ; read the floating bus ; 4
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bne zxloop ; if not, start from scratch ; 2/3
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dex ; we were, dec ; 2
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bne wiloop ; if not 4 of them, restart ; 3/2
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; if we get here we read 4 proper pixels, 11 apart (2+4+2+2+3)
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; 0 11 22 33, clock at 34
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; 1 12 23 34, clock at 35
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; 2 13 24 35, clock at 36
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; 3 14 25 36, clock at 37
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; 4 15 26 37, clock at 38
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; 5 16 27 38, clock at 39
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; 6 17 28 39, clock at 40
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; X X X X
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; X X X X
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; X X X X
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; X X X X
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; X X X X
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; X X X X
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; X X X X
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; 0123456789012345678901234 0123456789012345678901234567890123456789
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; 1 2 1 2 3
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; hsync pixels
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; XXXXXXXXXXXXXXXXXXXXXXXXX 4444444444444444444444444444440123456789
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; now look for the color change that
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; happens at line 13*8 = 104
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lda #$dd ; 2
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zloop:
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ldx #$04 ; 2
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qloop:
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cmp $C051 ; read floating bus ; 4
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bne zloop ; 2/3
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dex ; 2
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bne qloop ; 3/2
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;============
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; 11
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; Found it!
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; if we get here we read 4 proper pixels, 11 apart (2+4+2+2+3)
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; 0 11 22 33, clock at 34
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; 1 12 23 34, clock at 35
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; 2 13 24 35, clock at 36
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; 3 14 25 36, clock at 37
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; 4 15 26 37, clock at 38
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; 5 16 27 38, clock at 39
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; 6 17 28 39, clock at 40
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;btt:
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; jmp btt
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; In theory near end of line 104
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; now skip ahead 8 lines and read from the rainbow pattern we set
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; up to find our exact location
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; delay 65 * 8 = 520
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; we back off a few to make sure we're not in the horiz blank
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; try to delay 510
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; *NOTE* sometimes we end up going one (or rarely, two??) lines too far
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; so instead try going 7 lines ahead, and if still dd then one more
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; so single step until we get a rainbow color
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; go to next line, -10
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lda #28 ; 2
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jsr delay_a ; delay 25+28 = 53
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; total delay = 55
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vl_try_again:
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lda #29 ; 2
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jsr delay_a ; delay 25+29 = 54
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; total delay = 56
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lda $C051 ; 4
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cmp #$dd ; 2
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beq vl_try_again ; 3
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; -1
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; now near end of line 112
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;lda $0 ; nop to match old code ; 3
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; nop ; nop to match old code ; 2
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lda $C051 ; 4
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;kbb:
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; jmp kbb
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; we are in theory on line $728 = 14*8 = 112
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; so 112*65 = 7280 cycles from start
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; we are actualy 25+20+A pixels in
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; 7325+A
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; Our goal is line 114 at 7410 cycles
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; 7410 - 7325 = 85
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; so kill 85-A cycles
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; -6 to do subtraction
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; -6 for rts
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; -25 for delay_a overhead
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eor #$ff ; 2
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sec ; 2
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adc #48 ; 2
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jsr delay_a ; should total 48 cycles
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done_vapor_lock:
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rts ; 6
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; Some random related work
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; Docs:
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; Lancaster
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; Bishop
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; Sather
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; Vaguely relevant but no help with the Apple II+ issue
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;
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; Eamon: Screen display and timing synchronization
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; on the Apple IIe and Apple IIgs
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;
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; Adams: Visually presented verbal stimuli by assembly
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; language on the Apple II computer.
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; Cavanagh and Anstis: Visual psychophysics on the
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; Apple II: Getting started
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@ -0,0 +1,25 @@
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; From http://6502org.wikidot.com/software-delay
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; 25+A cycles (including JSR), 19 bytes (excluding JSR)
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;
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; The branches must not cross page boundaries!
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;
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|
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; Cycles Accumulator Carry flag
|
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; 0 1 2 3 4 5 6 (hex) 0 1 2 3 4 5 6
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|
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; jsr delay_a ; 6 6 6 6 6 6 6 00 01 02 03 04 05 06
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|
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dly0: sbc #7
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delay_a:cmp #7 ; 2 2 2 2 2 2 2 00 01 02 03 04 05 06 0 0 0 0 0 0 0
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bcs dly0 ; 2 2 2 2 2 2 2 00 01 02 03 04 05 06 0 0 0 0 0 0 0
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lsr ; 2 2 2 2 2 2 2 00 00 01 01 02 02 03 0 1 0 1 0 1 0
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bcs dly1 ; 2 3 2 3 2 3 2 00 00 01 01 02 02 03 0 1 0 1 0 1 0
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dly1: beq dly2 ; 3 3 2 2 2 2 2 00 00 01 01 02 02 03 0 1 0 1 0 1 0
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lsr ; 2 2 2 2 2 00 00 01 01 01 1 1 0 0 1
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beq dly3 ; 3 3 2 2 2 00 00 01 01 01 1 1 0 0 1
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bcc dly3 ; 3 3 2 01 01 01 0 0 1
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dly2: bne dly3 ; 2 2 3 00 00 01 0 1 0
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dly3: rts ; 6 6 6 6 6 6 6 00 00 00 00 01 01 01 0 1 1 1 0 0 1
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;
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; Total cycles: 25 26 27 28 29 30 31
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|
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@ -134,85 +134,37 @@ in_range:
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; setup graphics for vapor lock
|
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;==============================
|
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|
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; Clear Page0
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lda #$0
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sta DRAW_PAGE
|
||||
lda #$44
|
||||
jsr clear_gr
|
||||
jsr vapor_lock
|
||||
|
||||
; Make screen half green
|
||||
lda #$11
|
||||
ldy #24
|
||||
jsr clear_page_loop
|
||||
|
||||
|
||||
;=====================================================
|
||||
; attempt vapor lock
|
||||
; by reading the "floating bus" we can see most recently
|
||||
; written value of the display
|
||||
; we look for $55 (which is the grey line)
|
||||
;=====================================================
|
||||
; See:
|
||||
; Have an Apple Split by Bob Bishop
|
||||
; Softalk, October 1982
|
||||
|
||||
; Challenges: each scan line scans 40 bytes.
|
||||
; The blanking happens at the *beginning*
|
||||
; So 65 bytes are scanned, starting at adress of the line - 25
|
||||
|
||||
; the scan takes 8 cycles, look for 4 repeats of the value
|
||||
; to avoid false positive found if the horiz blanking is mirroring
|
||||
; the line (max 3 repeats in that case)
|
||||
|
||||
vapor_lock_loop: ; first make sure we have all zeroes
|
||||
LDA #$11
|
||||
zxloop:
|
||||
LDX #$04
|
||||
wiloop:
|
||||
CMP $C051
|
||||
BNE zxloop
|
||||
DEX
|
||||
BNE wiloop
|
||||
|
||||
LDA #$44 ; now look for our border color (4 times)
|
||||
zloop:
|
||||
LDX #$04
|
||||
qloop:
|
||||
CMP $C051
|
||||
BNE zloop
|
||||
DEX
|
||||
BNE qloop
|
||||
|
||||
; found first line of black after green, at up to line 26 on screen
|
||||
; so we want roughly 22 lines * 4 = 88*65 = 5720 + 4550 = 10270
|
||||
; - 65 (for the scanline we missed) = 10205 - 12 = 10193
|
||||
|
||||
jsr gr_copy_to_current ; 6+ 9292
|
||||
; 10193 - 9298 = 895
|
||||
; Fudge factor (unknown) -30 = 865
|
||||
; vapor lock returns with us at beginning of hsync in line
|
||||
; 114 (7410 cycles), so with 5070 lines to go
|
||||
|
||||
; GR part
|
||||
bit LORES ; 4
|
||||
bit SET_GR ; 4
|
||||
bit FULLGR ; 4
|
||||
|
||||
; Try X=88 Y=2 cycles=893 R2
|
||||
jsr gr_copy_to_current ; 6+ 9292
|
||||
|
||||
nop
|
||||
ldy #2 ; 2
|
||||
loopA:
|
||||
ldx #88 ; 2
|
||||
loopB:
|
||||
dex ; 2
|
||||
bne loopB ; 2nt/3
|
||||
; now we have 322 left
|
||||
|
||||
dey ; 2
|
||||
bne loopA ; 2nt/3
|
||||
; 322 - 12 = 310
|
||||
; - 3 for jmp
|
||||
; 307
|
||||
|
||||
; Try X=9 Y=6 cycles=307
|
||||
|
||||
ldy #6 ; 2
|
||||
loopA: ldx #9 ; 2
|
||||
loopB: dex ; 2
|
||||
bne loopB ; 2nt/3
|
||||
dey ; 2
|
||||
bne loopA ; 2nt/3
|
||||
|
||||
jmp display_loop ; 3
|
||||
|
||||
jmp display_loop
|
||||
.align $100
|
||||
|
||||
|
||||
;================================================
|
||||
; Display Loop
|
||||
;================================================
|
||||
|
|
@ -342,6 +294,8 @@ gr_offsets:
|
|||
.include "../asm_routines/gr_unrle.s"
|
||||
.include "../asm_routines/keypress.s"
|
||||
.include "gr_copy.s"
|
||||
.include "vapor_lock.s"
|
||||
.include "delay_a.s"
|
||||
|
||||
pictures:
|
||||
.word k_low,k_high
|
||||
|
|
|
|||
|
|
@ -0,0 +1,238 @@
|
|||
; This took a while to track down
|
||||
; On Apple II/II+ the horiz blanking addr are $1000 higher than on IIe
|
||||
; So on II+ were outside video area, so unlikely to be our set value
|
||||
; (unless I foolishly use $ff which some uninitialized mem is set to)
|
||||
; Lots of this color fiddling is to make sure you don't accidentally
|
||||
; get runs of colors on IIe due to the horiz blank
|
||||
|
||||
; 0-5 aqua 6-12 = grey, 13 - 20 = yellow, 21-23 = aqua rainbow 14
|
||||
;
|
||||
;
|
||||
;16 0 YA
|
||||
;17 1 YA
|
||||
;18 2 YA
|
||||
;19 3 YA
|
||||
;20 4 YA
|
||||
;21 5 AA
|
||||
;22 6 AG
|
||||
;23 7 AG
|
||||
;0 8 AG
|
||||
;1 9 AG
|
||||
;2 10 AG
|
||||
;3 11 AG
|
||||
;4 12 AG
|
||||
;5 13 AY ****
|
||||
;6 14 GY RAINBOW
|
||||
;7 15 GY
|
||||
;8 16 GY
|
||||
;9 17 GY
|
||||
;10 18 GY
|
||||
;11 19 GY
|
||||
;12 20 GY
|
||||
;13 21 YA
|
||||
;14 22 YA
|
||||
;15 23 YA
|
||||
|
||||
|
||||
|
||||
;==============================
|
||||
; setup graphics for vapor lock
|
||||
;==============================
|
||||
vapor_lock:
|
||||
|
||||
; Clear Page0
|
||||
lda #$0
|
||||
sta DRAW_PAGE
|
||||
lda #$ee ; full screen white $ff
|
||||
jsr clear_gr
|
||||
|
||||
lda #$dd
|
||||
ldy #40
|
||||
jsr clear_page_loop ; make bottom half yellow $dd
|
||||
|
||||
lda #$aa
|
||||
ldy #24
|
||||
jsr clear_page_loop ; make middle grey2 $aa
|
||||
|
||||
lda #$ee
|
||||
ldy #10
|
||||
jsr clear_page_loop ; make top half aqua $ee
|
||||
|
||||
; set up a rainbow to aid in exact lock
|
||||
|
||||
ldy #00
|
||||
rainbow_loop:
|
||||
tya
|
||||
sta $728+20,Y
|
||||
iny
|
||||
cpy #20
|
||||
bne rainbow_loop
|
||||
|
||||
;btt:
|
||||
; jmp btt
|
||||
|
||||
|
||||
;=====================================================
|
||||
; attempt vapor lock
|
||||
; by reading the "floating bus" we can see most recently
|
||||
; written value of the display
|
||||
;=====================================================
|
||||
; See:
|
||||
; Have an Apple Split by Bob Bishop
|
||||
; Softalk, October 1982
|
||||
|
||||
; Challenges: each scan line scans 40 bytes.
|
||||
; The blanking happens at the *beginning*
|
||||
; So 65 bytes are scanned, starting at adress of the line - 25
|
||||
|
||||
; the scan takes 8 cycles, look for 4 repeats of the value
|
||||
; to avoid false positive found if the horiz blanking is mirroring
|
||||
; the line (max 3 repeats in that case)
|
||||
|
||||
vapor_lock_loop:
|
||||
|
||||
; first make sure we have a full line of $aa
|
||||
|
||||
lda #$aa ; 2
|
||||
zxloop:
|
||||
ldx #$04 ; 2
|
||||
wiloop:
|
||||
cmp $C051 ; read the floating bus ; 4
|
||||
bne zxloop ; if not, start from scratch ; 2/3
|
||||
dex ; we were, dec ; 2
|
||||
bne wiloop ; if not 4 of them, restart ; 3/2
|
||||
|
||||
; if we get here we read 4 proper pixels, 11 apart (2+4+2+2+3)
|
||||
; 0 11 22 33, clock at 34
|
||||
; 1 12 23 34, clock at 35
|
||||
; 2 13 24 35, clock at 36
|
||||
; 3 14 25 36, clock at 37
|
||||
; 4 15 26 37, clock at 38
|
||||
; 5 16 27 38, clock at 39
|
||||
; 6 17 28 39, clock at 40
|
||||
|
||||
|
||||
; X X X X
|
||||
; X X X X
|
||||
; X X X X
|
||||
; X X X X
|
||||
; X X X X
|
||||
; X X X X
|
||||
; X X X X
|
||||
; 0123456789012345678901234 0123456789012345678901234567890123456789
|
||||
; 1 2 1 2 3
|
||||
; hsync pixels
|
||||
; XXXXXXXXXXXXXXXXXXXXXXXXX 4444444444444444444444444444440123456789
|
||||
|
||||
; now look for the color change that
|
||||
; happens at line 13*8 = 104
|
||||
|
||||
lda #$dd ; 2
|
||||
zloop:
|
||||
ldx #$04 ; 2
|
||||
qloop:
|
||||
cmp $C051 ; read floating bus ; 4
|
||||
bne zloop ; 2/3
|
||||
dex ; 2
|
||||
bne qloop ; 3/2
|
||||
;============
|
||||
; 11
|
||||
|
||||
; Found it!
|
||||
; if we get here we read 4 proper pixels, 11 apart (2+4+2+2+3)
|
||||
; 0 11 22 33, clock at 34
|
||||
; 1 12 23 34, clock at 35
|
||||
; 2 13 24 35, clock at 36
|
||||
; 3 14 25 36, clock at 37
|
||||
; 4 15 26 37, clock at 38
|
||||
; 5 16 27 38, clock at 39
|
||||
; 6 17 28 39, clock at 40
|
||||
|
||||
|
||||
|
||||
|
||||
;btt:
|
||||
; jmp btt
|
||||
|
||||
; In theory near end of line 104
|
||||
|
||||
; now skip ahead 8 lines and read from the rainbow pattern we set
|
||||
; up to find our exact location
|
||||
|
||||
; delay 65 * 8 = 520
|
||||
; we back off a few to make sure we're not in the horiz blank
|
||||
; try to delay 510
|
||||
|
||||
; *NOTE* sometimes we end up going one (or rarely, two??) lines too far
|
||||
; so instead try going 7 lines ahead, and if still dd then one more
|
||||
|
||||
; so single step until we get a rainbow color
|
||||
|
||||
; go to next line, -10
|
||||
lda #28 ; 2
|
||||
jsr delay_a ; delay 25+28 = 53
|
||||
; total delay = 55
|
||||
|
||||
vl_try_again:
|
||||
lda #29 ; 2
|
||||
jsr delay_a ; delay 25+29 = 54
|
||||
; total delay = 56
|
||||
|
||||
|
||||
|
||||
lda $C051 ; 4
|
||||
cmp #$dd ; 2
|
||||
beq vl_try_again ; 3
|
||||
; -1
|
||||
|
||||
|
||||
; now near end of line 112
|
||||
;lda $0 ; nop to match old code ; 3
|
||||
; nop ; nop to match old code ; 2
|
||||
|
||||
lda $C051 ; 4
|
||||
;kbb:
|
||||
; jmp kbb
|
||||
|
||||
; we are in theory on line $728 = 14*8 = 112
|
||||
; so 112*65 = 7280 cycles from start
|
||||
|
||||
; we are actualy 25+20+A pixels in
|
||||
; 7325+A
|
||||
|
||||
; Our goal is line 114 at 7410 cycles
|
||||
; 7410 - 7325 = 85
|
||||
|
||||
; so kill 85-A cycles
|
||||
; -6 to do subtraction
|
||||
; -6 for rts
|
||||
; -25 for delay_a overhead
|
||||
|
||||
eor #$ff ; 2
|
||||
sec ; 2
|
||||
adc #48 ; 2
|
||||
|
||||
jsr delay_a ; should total 48 cycles
|
||||
|
||||
|
||||
done_vapor_lock:
|
||||
rts ; 6
|
||||
|
||||
|
||||
|
||||
|
||||
; Some random related work
|
||||
; Docs:
|
||||
; Lancaster
|
||||
; Bishop
|
||||
; Sather
|
||||
|
||||
; Vaguely relevant but no help with the Apple II+ issue
|
||||
;
|
||||
; Eamon: Screen display and timing synchronization
|
||||
; on the Apple IIe and Apple IIgs
|
||||
;
|
||||
; Adams: Visually presented verbal stimuli by assembly
|
||||
; language on the Apple II computer.
|
||||
; Cavanagh and Anstis: Visual psychophysics on the
|
||||
; Apple II: Getting started
|
||||
Loading…
Reference in New Issue