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cc65/libsrc/apple2/cputc.s
Oliver Schmidt 1644bcdf03 Implemented line wrap.
According to https://github.com/cc65/wiki/wiki/Direct-console-IO it is undefined what happens when the end of the sceen is reached. But it is _not_ undefined what happens when the end of the line is reached. So implement the usual thing - which was easy enough to do after all.
2018-08-20 00:30:17 +02:00

99 lines
2.8 KiB
ArmAsm

;
; Ullrich von Bassewitz, 06.08.1998
;
; void __fastcall__ cputcxy (unsigned char x, unsigned char y, char c);
; void __fastcall__ cputc (char c);
;
.ifdef __APPLE2ENH__
.constructor initconio
.endif
.export _cputcxy, _cputc
.export cputdirect, newline, putchar, putchardirect
.import gotoxy, VTABZ
.include "apple2.inc"
.segment "ONCE"
.ifdef __APPLE2ENH__
initconio:
sta SETALTCHAR ; Switch in alternate charset
bit LORES ; Limit SET80COL-HISCR to text
rts
.endif
.code
; Plot a character - also used as internal function
_cputcxy:
pha ; Save C
jsr gotoxy ; Call this one, will pop params
pla ; Restore C and run into _cputc
_cputc:
cmp #$0D ; Test for \r = carrage return
beq left
cmp #$0A ; Test for \n = line feed
beq newline
eor #$80 ; Invert high bit
.ifndef __APPLE2ENH__
cmp #$E0 ; Test for lowercase
bcc cputdirect
and #$DF ; Convert to uppercase
.endif
cputdirect:
jsr putchar
inc CH ; Bump to next column
lda CH
cmp WNDWDTH
bcc :+
jsr newline
left: lda #$00 ; Goto left edge of screen
sta CH
: rts
newline:
inc CV ; Bump to next line
lda CV
cmp WNDBTM
bcc :+
lda WNDTOP ; Goto top of screen
sta CV
: jmp VTABZ
putchar:
.ifdef __APPLE2ENH__
ldy INVFLG
cpy #$FF ; Normal character display mode?
beq putchardirect
cmp #$E0 ; Lowercase?
bcc mask
and #$7F ; Inverse lowercase
bra putchardirect
.endif
mask: and INVFLG ; Apply normal, inverse, flash
putchardirect:
pha
ldy CH
.ifdef __APPLE2ENH__
bit RD80VID ; In 80 column mode?
bpl put ; No, just go ahead
tya
lsr ; Div by 2
tay
bcs put ; Odd cols go in main memory
bit HISCR ; Assume SET80COL
.endif
put: lda (BASL),Y ; Get current character
tax ; Return old character for _cgetc
pla
sta (BASL),Y
.ifdef __APPLE2ENH__
bit LOWSCR ; Doesn't hurt in 40 column mode
.endif
rts