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;
; Ullrich von Bassewitz, 06.08.1998
;
; char cgetc (void);
;
.export _cgetc
.import plot, write_crtc
.import cursor
.import keyidx: zp, keybuf: zp, config: zp
_cgetc: lda keyidx ; Get number of characters
bne L2 ; Jump if there are already chars waiting
; Switch on the cursor if needed
lda cursor
beq L1 ; Jump if no cursor
jsr plot ; Set the current cursor position
ldy #10
lda config ; Cursor format
jsr write_crtc ; Set the cursor formar
L1: lda keyidx
beq L1
ldy #10
lda #$20 ; Cursor off
jsr write_crtc
L2: ldx #$00 ; Get index
ldy keybuf ; Get first character in the buffer
sei
L3: lda keybuf+1,x ; Move up the remaining chars
sta keybuf,x
inx
cpx keyidx
bne L3
dec keyidx
cli
ldx #$00 ; High byte
tya ; First char from buffer
rts
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