mirror of
https://github.com/cc65/cc65.git
synced 2024-11-02 18:06:48 +00:00
42 lines
458 B
ArmAsm
42 lines
458 B
ArmAsm
|
;
|
||
|
|
; Ullrich von Bassewitz, 23.09.1998
|
||
|
|
;
|
||
|
|
; unsigned readjoy (unsigned char joy);
|
||
|
|
;
|
||
|
|
|
||
|
|
.export _readjoy
|
||
|
|
|
||
|
|
.include "c64.inc"
|
||
|
|
|
||
|
|
|
||
|
|
.proc _readjoy
|
||
|
|
|
||
|
|
tax ; Joystick number into X
|
||
|
|
bne joy2
|
||
|
|
|
||
|
|
; Read joystick 1
|
||
|
|
|
||
|
|
joy1: lda #$7F
|
||
|
|
sei
|
||
|
|
sta CIA1_PRA
|
||
|
|
lda CIA1_PRB
|
||
|
|
cli
|
||
|
|
and #$1F
|
||
|
|
eor #$1F
|
||
|
|
rts
|
||
|
|
|
||
|
|
; Read joystick 2
|
||
|
|
|
||
|
|
joy2: ldx #0
|
||
|
|
lda #$E0
|
||
|
|
ldy #$FF
|
||
|
|
sta CIA1_DDRA
|
||
|
|
lda CIA1_PRA
|
||
|
|
sty CIA1_DDRA
|
||
|
|
and #$1F
|
||
|
|
eor #$1F
|
||
|
|
rts
|
||
|
|
|
||
|
|
.endproc
|
||
|
|
|