1
0
mirror of https://github.com/cc65/cc65.git synced 2024-10-31 04:04:49 +00:00
cc65/libsrc/c128/cputc.s
cuz ea4d2f4e6f Fixed several problems with the new output routines
git-svn-id: svn://svn.cc65.org/cc65/trunk@1823 b7a2c559-68d2-44c3-8de9-860c34a00d81
2002-12-21 14:11:32 +00:00

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