cc65/libsrc/pce/cpeekc.s

25 lines
573 B
ArmAsm

;
; 2020-07-14, Groepaz
;
; char cpeekc (void);
;
; get character from current position, do NOT advance cursor
.export _cpeekc
.include "pce.inc"
.include "extzp.inc"
_cpeekc:
st0 #VDC_MARR ; Memory-Address Read
ldy SCREEN_PTR
ldx SCREEN_PTR+1
sty VDC_DATA_LO
stx VDC_DATA_HI
st0 #VDC_VRR ; VRAM Read Register
lda VDC_DATA_LO ; character
and #<~$80 ; remove reverse bit
ldx #0
rts