1
0
mirror of https://github.com/cc65/cc65.git synced 2024-11-15 11:05:56 +00:00
cc65/libsrc/nes/cputc.s
Oliver Schmidt 419eb700b5 Renamed INITBSS to INIT and INIT to ONCE.
The way we want to use the INITBSS segment - and especially the fact that it won't have the type bss on all ROM based targets - means that the name INITBSS is misleading. After all INIT is the best name from my perspective as it serves several purposes and therefore needs a rather generic name.

Unfortunately this means that the current INIT segment needs to be renamed too. Looking for a short (ideally 4 letter) name I came up with ONCE as it contains all code (and data) accessed only once during initialization.
2016-03-06 21:27:19 +01:00

95 lines
2.2 KiB
ArmAsm

;
; Written by Groepaz/Hitmen <groepaz@gmx.net>
; Cleanup by Ullrich von Bassewitz <uz@cc65.org>
;
; void cputcxy (unsigned char x, unsigned char y, char c);
; void cputc (char c);
;
.export _cputcxy, _cputc, cputdirect, putchar
.export newline
.constructor initconio
.import popa, _gotoxy
.import ppuinit, paletteinit, ppubuf_put
.import setcursor
.importzp tmp3,tmp4
.include "nes.inc"
;-----------------------------------------------------------------------------
.code
_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 #$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
inc CURS_Y ; 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
jmp setcursor ; 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
ldy SCREEN_PTR+1
ldx SCREEN_PTR
jmp ppubuf_put
;-----------------------------------------------------------------------------
; Initialize the conio subsystem. Code goes into the ONCE segment, which may
; be reused after startup.
.segment "ONCE"
initconio:
jsr ppuinit
jsr paletteinit
lda #0
sta RVS
sta CURS_X
sta CURS_Y
jmp plot ; Set the cursor