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cc65/libsrc/pce/cputc.s
Oliver Schmidt 13482984ca Introduced internal gotoxy that pops both parameters.
About all CONIO functions offering a <...>xy variant call
  popa
  _gotoxy

By providing an internal gotoxy variant that starts with a popa all those CONIO function can be shortened by 3 bytes. As soon as program calls more than one CONIO function this means an overall code size reduction.
2016-06-05 14:58:38 +02:00

99 lines
2.1 KiB
ArmAsm

;
; void cputcxy (unsigned char x, unsigned char y, char c);
; void cputc (char c);
;
.export _cputcxy, _cputc, cputdirect, putchar
.export newline, plot
.import gotoxy
.import PLOT
.import xsize
.importzp tmp3,tmp4
.include "pce.inc"
.include "extzp.inc"
_cputcxy:
pha ; Save C
jsr gotoxy ; Set cursor, drop x and y
pla ; Restore C
; Plot a character - also used as internal function
_cputc: cmp #$0d ; CR?
bne L1
lda #0
sta CURS_X
beq plot ; Recalculate pointers
L1: cmp #$0a ; LF?
beq newline ; Recalculate pointers
; Printable char of some sort
cputdirect:
jsr putchar ; Write the character to the screen
; Advance cursor position
advance:
ldy CURS_X
iny
cpy xsize
bne L3
jsr newline ; new line
ldy #0 ; + cr
L3: sty CURS_X
jmp plot
newline:
inc CURS_Y
; 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 RVS ; Set revers bit
tax
st0 #VDC_MAWR ; Memory Adress Write
lda SCREEN_PTR
sta a:VDC_DATA_LO
lda SCREEN_PTR + 1
sta a:VDC_DATA_HI
st0 #VDC_VWR ; VWR
txa
sta a:VDC_DATA_LO ; character
lda CHARCOLOR
asl a
asl a
asl a
asl a
ora #$02
sta a:VDC_DATA_HI
rts
;-------------------------------------------------------------------------------
; force the init constructor to be imported
.import initconio
conio_init = initconio