mirror of
https://github.com/cc65/cc65.git
synced 2024-12-27 15:29:46 +00:00
103 lines
2.3 KiB
ArmAsm
103 lines
2.3 KiB
ArmAsm
;
|
|
; Mark Keates, Christian Groessler, Piotr Fusik, Karri Kaksonen
|
|
;
|
|
; void cputcxy (unsigned char x, unsigned char y, char c);
|
|
; void cputc (char c);
|
|
;
|
|
|
|
.export _mono_cputc
|
|
.import mono_gotox, mono_gotoy, pusha0
|
|
.import pushax
|
|
.import _mono_screen
|
|
|
|
.include "atari7800.inc"
|
|
.include "extzp.inc"
|
|
|
|
.code
|
|
|
|
;---------------------------------------------------------------------------
|
|
; 8x16 routine
|
|
|
|
umula0:
|
|
ldy #8 ; Number of bits
|
|
lda #0
|
|
lsr ptr7800 ; Get first bit into carry
|
|
@L0: bcc @L1
|
|
|
|
clc
|
|
adc ptrtmp
|
|
tax
|
|
lda ptrtmp+1 ; hi byte of left op
|
|
clc
|
|
adc ptr7800+1
|
|
sta ptr7800+1
|
|
txa
|
|
|
|
@L1: ror ptr7800+1
|
|
ror a
|
|
ror ptr7800
|
|
dey
|
|
bne @L0
|
|
tax
|
|
lda ptr7800 ; Load the result
|
|
rts
|
|
|
|
;-----------------------------------------------------------------------------
|
|
; Put a character on screen
|
|
;
|
|
; The code will handle newlines that wrap to start of screen
|
|
;
|
|
.proc _mono_cputc
|
|
|
|
cmp #$0A ; LF
|
|
bne @L4
|
|
@L1: lda #0 ; newline
|
|
jsr mono_gotox
|
|
lda CURS_Y
|
|
cmp #(screenrows-1)
|
|
bne @L2
|
|
lda #0
|
|
beq @L3
|
|
@L2: clc
|
|
adc #1
|
|
@L3: jmp mono_gotoy
|
|
|
|
@L4:
|
|
pha
|
|
|
|
lda #0
|
|
sta ptr7800+1
|
|
sta ptrtmp+1
|
|
lda CURS_Y ; Find position on screen buffer
|
|
sta ptr7800
|
|
lda #mono_charsperline
|
|
sta ptrtmp
|
|
jsr umula0
|
|
clc
|
|
adc CURS_X
|
|
bcc @L11
|
|
inx
|
|
@L11: clc
|
|
adc #<(_mono_screen)
|
|
sta ptr7800
|
|
bcc @L12
|
|
inx
|
|
@L12: txa
|
|
clc
|
|
adc #>(_mono_screen)
|
|
sta ptr7800+1
|
|
|
|
pla ; Print character on screen
|
|
ldy #0
|
|
sta (ptr7800),y
|
|
|
|
lda CURS_X ; Increment cursor
|
|
cmp #(mono_charsperline-1)
|
|
beq @L1
|
|
clc
|
|
adc #1
|
|
jmp mono_gotox
|
|
|
|
.endproc
|
|
|