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cc65/libsrc/atari/cgetc.s

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;
; Christian Groessler, November-2002
;
; get a char from the keyboard
; char cgetc(void)
;
.include "atari.inc"
.export _cgetc
.import cursor
_cgetc:
jsr setcursor
jsr @1
ldx #0
rts
@1: lda KEYBDV+5
pha
lda KEYBDV+4
pha
lda #12
sta ICAX1Z ; fix problems with direct call to KEYBDV
rts
.proc setcursor
lda OLDCHR ; get char at current cursor position
ldy #0 ; needed later
ldx cursor ; current cursor setting as requested by the user
beq off
ldx #0
beq cont
off: inx
cont: stx CRSINH ; update system variable
beq turnon
and #$7f ; clear high bit / inverse flag
finish: sta (OLDADR),y ; update on-screen display
rts
turnon: ora #$80 ; set high bit / inverse flag
bne finish
.endproc