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Don't shift in an unknown carry bit.

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If that bit happenned to be set, then it would defeat the fancy ADC shifter.
This commit is contained in:
Greg King
2013-09-05 11:32:50 -04:00
parent edc5ed4f54
commit eb741e1396
1 changed files with 2 additions and 2 deletions
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4
libsrc/cbm510/mou/cbm510-joy.s
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@@ -2,7 +2,7 @@
; Driver for a "joystick mouse". ; Driver for a "joystick mouse".
; ;
; 2009-09-26, Ullrich von Bassewitz ; 2009-09-26, Ullrich von Bassewitz
; 2013-08-22, Greg King ; 2013-09-05, Greg King
; ;
.include "zeropage.inc" .include "zeropage.inc"
@@ -252,7 +252,7 @@ BUTTONS:
; Joystick 1, fire button is in bit 6. ; Joystick 1, fire button is in bit 6.
and #%11000000 and #%11000000
rol a ; Move bits 7,6 to bits 1,0 asl a ; Move bits 7,6 to bits 1,0
rol a rol a
rol a rol a
adc #%00001110 ; Move bit 1 to bit 4 adc #%00001110 ; Move bit 1 to bit 4