mirror of
https://github.com/cc65/cc65.git
synced 2024-10-31 04:04:49 +00:00
51 lines
1.2 KiB
ArmAsm
51 lines
1.2 KiB
ArmAsm
;
|
|
; 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
|
|
|
|
|