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;
; void cputcxy (unsigned char x, unsigned char y, char c);
; void cputc (char c);
;
.export _cputcxy, _cputc, cputdirect, putchar
.export newline, plot
.forceimport initconio ; force conio initiation
.import gotoxy
.import PLOT
.import xsize
.importzp tmp3, tmp4
.include "pce.inc"
.include "extzp.inc"
_cputcxy:
pha ; Save C
jsr gotoxy ; Set cursor, drop x and y
pla ; Restore C
; Plot a character - also used as internal function
_cputc: cmp #$0D ; CR?
bne L1
stz CURS_X
bra plot ; Recalculate pointer
L1: cmp #$0A ; LF?
beq newline ; Recalculate pointer
; Printable char of some sort
cputdirect:
jsr putchar ; Write the character to the screen
; Move the cursor (rightwards) to the next position.
advance:
ldy CURS_X
iny
cpy xsize
bne L3
inc CURS_Y ; new line
cly ; + CR
L3: sty CURS_X
; Set cursor position; calculate VRAM pointer.
plot: ldy CURS_X
ldx CURS_Y
clc
jmp PLOT ; Set the new cursor
newline:
inc CURS_Y
bra plot
; Write one character to the screen without doing anything else.
putchar:
ora RVS ; Set reverse bit
st0 #VDC_MAWR ; Memory-Address Write
ldy SCREEN_PTR
ldx SCREEN_PTR+1
sty VDC_DATA_LO
stx VDC_DATA_HI
st0 #VDC_VWR
sta VDC_DATA_LO ; character
lda CHARCOLOR ; pallette number
asl a
asl a
asl a
asl a
ora #>$0200 ; high nybble of char. index
sta VDC_DATA_HI
rts
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