mirror of
https://github.com/cc65/cc65.git
synced 2024-11-04 17:04:58 +00:00
6d498d8187
to emulate these functions on platforms where one or more of these functions are not available (PET, CBM-II). git-svn-id: svn://svn.cc65.org/cc65/trunk@1544 b7a2c559-68d2-44c3-8de9-860c34a00d81
107 lines
1.8 KiB
ArmAsm
107 lines
1.8 KiB
ArmAsm
;
|
|
; Ullrich von Bassewitz, 06.08.1998
|
|
;
|
|
; void cputcxy (unsigned char x, unsigned char y, char c);
|
|
; void cputc (char c);
|
|
;
|
|
|
|
.export _cputcxy, _cputc, cputdirect, putchar
|
|
.export newline, plot
|
|
.import popa, _gotoxy
|
|
.import xsize, revers
|
|
.import PLOT
|
|
|
|
.include "vic20.inc"
|
|
|
|
|
|
_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?
|
|
bne L1
|
|
lda #0
|
|
sta CURS_X
|
|
beq plot ; Recalculate pointers
|
|
|
|
L1: cmp #$0D ; LF?
|
|
beq newline ; Recalculate pointers
|
|
|
|
; Printable char of some sort
|
|
|
|
cmp #' '
|
|
bcc cputdirect ; Other control char
|
|
tay
|
|
bmi L10
|
|
cmp #$60
|
|
bcc L2
|
|
and #$DF
|
|
bne cputdirect ; Branch always
|
|
L2: and #$3F
|
|
|
|
cputdirect:
|
|
jsr putchar ; Write the character to the screen
|
|
|
|
; Advance cursor position
|
|
|
|
advance:
|
|
iny
|
|
cpy xsize
|
|
bne L3
|
|
jsr newline ; new line
|
|
ldy #0 ; + cr
|
|
L3: sty CURS_X
|
|
rts
|
|
|
|
newline:
|
|
clc
|
|
lda xsize
|
|
adc SCREEN_PTR
|
|
sta SCREEN_PTR
|
|
bcc L4
|
|
inc SCREEN_PTR+1
|
|
clc
|
|
L4: lda xsize
|
|
adc CRAM_PTR
|
|
sta CRAM_PTR
|
|
bcc L5
|
|
inc CRAM_PTR+1
|
|
L5: inc CURS_Y
|
|
rts
|
|
|
|
; Handle character if high bit set
|
|
|
|
L10: and #$7F
|
|
cmp #$7E ; PI?
|
|
bne L11
|
|
lda #$5E ; Load screen code for PI
|
|
bne cputdirect
|
|
L11: ora #$40
|
|
bne cputdirect
|
|
|
|
|
|
|
|
; 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:
|
|
ora revers ; Set revers bit
|
|
ldy CURS_X
|
|
sta (SCREEN_PTR),y ; Set char
|
|
lda CHARCOLOR
|
|
sta (CRAM_PTR),y ; Set color
|
|
rts
|