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Fix lower nibble on read

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This commit is contained in:
Terence Boldt 2020-12-10 22:08:39 -05:00
parent b7d92c34f1
commit b8f5fcc34d
2 changed files with 21 additions and 23 deletions
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1
Firmware/Driver.asm
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@ -154,7 +154,6 @@ GetByte:
jsr GetNibble
and #$0f
ora NibbleStorage
lda NibbleStorage
rts
GetNibble:

43
Firmware/Driver.lst
View File

@ -1,4 +1,4 @@
ca65 V2.19 - Git b22d8c74
ca65 V2.18 - Ubuntu 2.18-1
Main file : Driver.asm
Current file: Driver.asm
@ -149,31 +149,30 @@ Current file: Driver.asm
0010AF 1 60 rts
0010B0 1
0010B0 1 GetByte:
0010B0 1 20 C3 10 jsr GetNibble
0010B0 1 20 C1 10 jsr GetNibble
0010B3 1 0A asl
0010B4 1 0A asl
0010B5 1 0A asl
0010B6 1 0A asl
0010B7 1 85 1D sta NibbleStorage
0010B9 1 20 C3 10 jsr GetNibble
0010B9 1 20 C1 10 jsr GetNibble
0010BC 1 29 0F and #$0f
0010BE 1 05 1D ora NibbleStorage
0010C0 1 A5 1D lda NibbleStorage
0010C2 1 60 rts
0010C3 1
0010C3 1 GetNibble:
0010C3 1 A9 B0 lda #$b0 ;set read flag low
0010C5 1 8D DD C0 sta OutputByte
0010C8 1 waitRead:
0010C8 1 AD DE C0 lda InputByte
0010CB 1 30 FB bmi waitRead
0010CD 1 09 F0 ora #$f0 ;set all flags high
0010CF 1 8D DD C0 sta OutputByte
0010D2 1 48 pha
0010D3 1 finishRead:
0010D3 1 AD DE C0 lda InputByte
0010D6 1 10 FB bpl finishRead
0010D8 1 68 pla
0010D9 1 60 rts
0010DA 1
0010DA 1
0010C0 1 60 rts
0010C1 1
0010C1 1 GetNibble:
0010C1 1 A9 B0 lda #$b0 ;set read flag low
0010C3 1 8D DD C0 sta OutputByte
0010C6 1 waitRead:
0010C6 1 AD DE C0 lda InputByte
0010C9 1 30 FB bmi waitRead
0010CB 1 09 F0 ora #$f0 ;set all flags high
0010CD 1 8D DD C0 sta OutputByte
0010D0 1 48 pha
0010D1 1 finishRead:
0010D1 1 AD DE C0 lda InputByte
0010D4 1 10 FB bpl finishRead
0010D6 1 68 pla
0010D7 1 60 rts
0010D8 1
0010D8 1