mirror of
https://github.com/cc65/cc65.git
synced 2024-12-29 13:31:59 +00:00
88 lines
1.7 KiB
ArmAsm
88 lines
1.7 KiB
ArmAsm
;
|
|
; Ullrich von Bassewitz, 2000-08-06, 2002-12-21
|
|
; Using lots of code from MagerValp, MagerValp@cling.gu.se
|
|
;
|
|
; void cputcxy (unsigned char x, unsigned char y, char c);
|
|
; void cputc (char c);
|
|
;
|
|
|
|
.export _cputcxy, _cputc, cputdirect, putchar
|
|
.export newline, plot
|
|
.constructor initcputc
|
|
.destructor donecputc
|
|
.import popa, _gotoxy
|
|
.import PLOT
|
|
|
|
.include "c128.inc"
|
|
|
|
cputdirect = PRINT
|
|
newline = NEWLINE
|
|
|
|
|
|
_cputcxy:
|
|
pha ; Save C
|
|
jsr popa ; Get Y
|
|
jsr _gotoxy ; Set cursor, drop x
|
|
pla ; Restore C
|
|
|
|
; Plot a character - also used as internal function
|
|
|
|
_cputc: cmp #$0A ; CR?
|
|
beq cr ; Output a cr
|
|
|
|
cmp #$0D ; LF?
|
|
bne L2
|
|
jmp NEWLINE ; Update cursor position
|
|
|
|
; Printable char of some sort
|
|
|
|
L2: cmp #' '
|
|
bcc L4 ; Other control char
|
|
tay
|
|
bmi L5
|
|
cmp #$60
|
|
bcc L3
|
|
and #$DF
|
|
bne L4 ; Branch always
|
|
L3: and #$3F
|
|
L4: jmp PRINT ; Output character
|
|
|
|
; Handle character if high bit set
|
|
|
|
L5: and #$7F
|
|
cmp #$7E ; PI?
|
|
bne L6
|
|
lda #$5E ; Load screen code for PI
|
|
bne L4
|
|
L6: ora #$40
|
|
bne L4 ; Branch always
|
|
|
|
; Carriage return
|
|
|
|
cr: lda #0
|
|
sta CURS_X
|
|
|
|
; Set cursor position, calculate RAM pointers
|
|
|
|
plot: ldy CURS_X
|
|
ldx CURS_Y
|
|
clc
|
|
jmp PLOT ; Set the new cursor
|
|
|
|
; Write one character to the screen without doing anything else, return X
|
|
; position in Y
|
|
|
|
putchar = $CC2F
|
|
|
|
;--------------------------------------------------------------------------
|
|
; Module constructor/destructor
|
|
|
|
initcputc:
|
|
lda #$C0
|
|
.byte $2C
|
|
donecputc:
|
|
lda #$00
|
|
sta SCROLL
|
|
rts
|
|
|