mirror of
https://github.com/irmen/prog8.git
synced 2024-08-20 21:29:18 +00:00
697 lines
16 KiB
Lua
697 lines
16 KiB
Lua
; Prog8 definitions for the Text I/O and Screen routines for the CommanderX16
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;
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; Written by Irmen de Jong (irmen@razorvine.net) - license: GNU GPL 3.0
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;
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; indent format: TABS, size=8
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%target cx16
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%import syslib
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%import conv
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txt {
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const ubyte DEFAULT_WIDTH = 80
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const ubyte DEFAULT_HEIGHT = 60
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sub clear_screen() {
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clear_screenchars(' ')
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}
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asmsub fill_screen (ubyte char @ A, ubyte color @ Y) clobbers(A) {
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; ---- fill the character screen with the given fill character and character color.
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%asm {{
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sty _ly+1
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phx
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pha
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jsr c64.SCREEN ; get dimensions in X/Y
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txa
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lsr a
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lsr a
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sta _lx+1
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stz cx16.VERA_CTRL
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lda #%00010000
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sta cx16.VERA_ADDR_H ; enable auto increment by 1, bank 0.
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stz cx16.VERA_ADDR_L ; start at (0,0)
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stz cx16.VERA_ADDR_M
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pla
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_lx ldx #0 ; modified
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phy
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_ly ldy #1 ; modified
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- sta cx16.VERA_DATA0
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sty cx16.VERA_DATA0
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sta cx16.VERA_DATA0
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sty cx16.VERA_DATA0
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sta cx16.VERA_DATA0
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sty cx16.VERA_DATA0
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sta cx16.VERA_DATA0
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sty cx16.VERA_DATA0
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dex
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bne -
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ply
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dey
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beq +
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stz cx16.VERA_ADDR_L
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inc cx16.VERA_ADDR_M ; next line
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bra _lx
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+ plx
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rts
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}}
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}
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asmsub clear_screenchars (ubyte char @ A) clobbers(Y) {
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; ---- clear the character screen with the given fill character (leaves colors)
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; (assumes screen matrix is at the default address)
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%asm {{
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phx
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pha
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jsr c64.SCREEN ; get dimensions in X/Y
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txa
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lsr a
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lsr a
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sta _lx+1
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stz cx16.VERA_CTRL
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lda #%00100000
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sta cx16.VERA_ADDR_H ; enable auto increment by 2, bank 0.
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stz cx16.VERA_ADDR_L ; start at (0,0)
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stz cx16.VERA_ADDR_M
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pla
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_lx ldx #0 ; modified
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- sta cx16.VERA_DATA0
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sta cx16.VERA_DATA0
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sta cx16.VERA_DATA0
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sta cx16.VERA_DATA0
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dex
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bne -
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dey
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beq +
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stz cx16.VERA_ADDR_L
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inc cx16.VERA_ADDR_M ; next line
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bra _lx
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+ plx
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rts
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}}
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}
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asmsub clear_screencolors (ubyte color @ A) clobbers(Y) {
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; ---- clear the character screen colors with the given color (leaves characters).
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; (assumes color matrix is at the default address)
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%asm {{
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phx
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sta _la+1
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jsr c64.SCREEN ; get dimensions in X/Y
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txa
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lsr a
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lsr a
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sta _lx+1
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stz cx16.VERA_CTRL
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lda #%00100000
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sta cx16.VERA_ADDR_H ; enable auto increment by 2, bank 0.
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lda #1
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sta cx16.VERA_ADDR_L ; start at (1,0)
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stz cx16.VERA_ADDR_M
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_lx ldx #0 ; modified
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_la lda #0 ; modified
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- sta cx16.VERA_DATA0
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sta cx16.VERA_DATA0
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sta cx16.VERA_DATA0
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sta cx16.VERA_DATA0
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dex
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bne -
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dey
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beq +
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lda #1
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sta cx16.VERA_ADDR_L
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inc cx16.VERA_ADDR_M ; next line
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bra _lx
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+ plx
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rts
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}}
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}
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ubyte[16] color_to_charcode = [$90,$05,$1c,$9f,$9c,$1e,$1f,$9e,$81,$95,$96,$97,$98,$99,$9a,$9b]
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sub color (ubyte txtcol) {
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c64.CHROUT(color_to_charcode[txtcol & 15])
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}
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sub color2 (ubyte txtcol, ubyte bgcol) {
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c64.CHROUT(color_to_charcode[bgcol & 15])
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c64.CHROUT(1) ; switch fg and bg colors
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c64.CHROUT(color_to_charcode[txtcol & 15])
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}
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sub lowercase() {
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cx16.screen_set_charset(3, 0) ; lowercase charset
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}
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sub uppercase() {
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cx16.screen_set_charset(2, 0) ; uppercase charset
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}
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asmsub scroll_left (ubyte dummy @ Pc) clobbers(A, Y) {
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; ---- scroll the whole screen 1 character to the left
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; contents of the rightmost column are unchanged, you should clear/refill this yourself
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; Carry flag is a dummy on the cx16
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%asm {{
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phx
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jsr c64.SCREEN
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dex
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stx _lx+1
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dey
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sty P8ZP_SCRATCH_B1 ; number of rows to scroll
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_nextline
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stz cx16.VERA_CTRL ; data port 0: source column
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lda #%00010000 ; auto increment 1
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sta cx16.VERA_ADDR_H
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lda #2
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sta cx16.VERA_ADDR_L ; begin in column 1
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ldy P8ZP_SCRATCH_B1
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sty cx16.VERA_ADDR_M
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lda #1
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sta cx16.VERA_CTRL ; data port 1: destination column
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lda #%00010000 ; auto increment 1
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sta cx16.VERA_ADDR_H
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stz cx16.VERA_ADDR_L
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sty cx16.VERA_ADDR_M
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_lx ldx #0 ; modified
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- lda cx16.VERA_DATA0
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sta cx16.VERA_DATA1 ; copy char
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lda cx16.VERA_DATA0
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sta cx16.VERA_DATA1 ; copy color
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dex
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bne -
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dec P8ZP_SCRATCH_B1
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bpl _nextline
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lda #0
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sta cx16.VERA_CTRL
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plx
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rts
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}}
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}
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asmsub scroll_right (ubyte dummy @ Pc) clobbers(A) {
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; ---- scroll the whole screen 1 character to the right
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; contents of the leftmost column are unchanged, you should clear/refill this yourself
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; Carry flag is a dummy on the cx16
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%asm {{
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phx
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jsr c64.SCREEN
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dex
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stx _lx+1
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txa
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asl a
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dea
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sta _rcol+1
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ina
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ina
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sta _rcol2+1
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dey
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sty P8ZP_SCRATCH_B1 ; number of rows to scroll
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_nextline
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stz cx16.VERA_CTRL ; data port 0: source column
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lda #%00011000 ; auto decrement 1
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sta cx16.VERA_ADDR_H
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_rcol lda #79*2-1 ; modified
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sta cx16.VERA_ADDR_L ; begin in rightmost column minus one
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ldy P8ZP_SCRATCH_B1
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sty cx16.VERA_ADDR_M
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lda #1
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sta cx16.VERA_CTRL ; data port 1: destination column
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lda #%00011000 ; auto decrement 1
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sta cx16.VERA_ADDR_H
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_rcol2 lda #79*2+1 ; modified
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sta cx16.VERA_ADDR_L
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sty cx16.VERA_ADDR_M
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_lx ldx #0 ; modified
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- lda cx16.VERA_DATA0
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sta cx16.VERA_DATA1 ; copy char
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lda cx16.VERA_DATA0
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sta cx16.VERA_DATA1 ; copy color
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dex
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bne -
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dec P8ZP_SCRATCH_B1
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bpl _nextline
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lda #0
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sta cx16.VERA_CTRL
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plx
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rts
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}}
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}
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asmsub scroll_up (ubyte dummy @ Pc) clobbers(A, Y) {
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; ---- scroll the whole screen 1 character up
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; contents of the bottom row are unchanged, you should refill/clear this yourself
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; Carry flag is a dummy on the cx16
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%asm {{
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phx
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jsr c64.SCREEN
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stx _nextline+1
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dey
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sty P8ZP_SCRATCH_B1
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stz cx16.VERA_CTRL ; data port 0 is source
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lda #1
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sta cx16.VERA_ADDR_M ; start at second line
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stz cx16.VERA_ADDR_L
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lda #%00010000
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sta cx16.VERA_ADDR_H ; enable auto increment by 1, bank 0.
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lda #1
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sta cx16.VERA_CTRL ; data port 1 is destination
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stz cx16.VERA_ADDR_M ; start at top line
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stz cx16.VERA_ADDR_L
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lda #%00010000
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sta cx16.VERA_ADDR_H ; enable auto increment by 1, bank 0.
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_nextline
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ldx #80 ; modified
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- lda cx16.VERA_DATA0
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sta cx16.VERA_DATA1 ; copy char
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lda cx16.VERA_DATA0
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sta cx16.VERA_DATA1 ; copy color
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dex
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bne -
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dec P8ZP_SCRATCH_B1
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beq +
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stz cx16.VERA_CTRL ; data port 0
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stz cx16.VERA_ADDR_L
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inc cx16.VERA_ADDR_M
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lda #1
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sta cx16.VERA_CTRL ; data port 1
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stz cx16.VERA_ADDR_L
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inc cx16.VERA_ADDR_M
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bra _nextline
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+ lda #0
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sta cx16.VERA_CTRL
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plx
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rts
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}}
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}
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asmsub scroll_down (ubyte dummy @ Pc) clobbers(A, Y) {
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; ---- scroll the whole screen 1 character down
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; contents of the top row are unchanged, you should refill/clear this yourself
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; Carry flag is a dummy on the cx16
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%asm {{
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phx
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jsr c64.SCREEN
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stx _nextline+1
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dey
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sty P8ZP_SCRATCH_B1
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stz cx16.VERA_CTRL ; data port 0 is source
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dey
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sty cx16.VERA_ADDR_M ; start at line before bottom line
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stz cx16.VERA_ADDR_L
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lda #%00010000
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sta cx16.VERA_ADDR_H ; enable auto increment by 1, bank 0.
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lda #1
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sta cx16.VERA_CTRL ; data port 1 is destination
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iny
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sty cx16.VERA_ADDR_M ; start at bottom line
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stz cx16.VERA_ADDR_L
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lda #%00010000
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sta cx16.VERA_ADDR_H ; enable auto increment by 1, bank 0.
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_nextline
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ldx #80 ; modified
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- lda cx16.VERA_DATA0
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sta cx16.VERA_DATA1 ; copy char
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lda cx16.VERA_DATA0
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sta cx16.VERA_DATA1 ; copy color
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dex
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bne -
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dec P8ZP_SCRATCH_B1
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beq +
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stz cx16.VERA_CTRL ; data port 0
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stz cx16.VERA_ADDR_L
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dec cx16.VERA_ADDR_M
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lda #1
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sta cx16.VERA_CTRL ; data port 1
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stz cx16.VERA_ADDR_L
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dec cx16.VERA_ADDR_M
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bra _nextline
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+ lda #0
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sta cx16.VERA_CTRL
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plx
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rts
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}}
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}
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romsub $FFD2 = chrout(ubyte char @ A) ; for consistency. You can also use c64.CHROUT directly ofcourse.
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asmsub print (str text @ AY) clobbers(A,Y) {
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; ---- print null terminated string from A/Y
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; note: the compiler contains an optimization that will replace
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; a call to this subroutine with a string argument of just one char,
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; by just one call to c64.CHROUT of that single char.
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%asm {{
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sta P8ZP_SCRATCH_B1
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sty P8ZP_SCRATCH_REG
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ldy #0
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- lda (P8ZP_SCRATCH_B1),y
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beq +
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jsr c64.CHROUT
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iny
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bne -
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+ rts
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}}
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}
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asmsub print_ub0 (ubyte value @ A) clobbers(A,Y) {
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; ---- print the ubyte in A in decimal form, with left padding 0s (3 positions total)
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%asm {{
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phx
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jsr conv.ubyte2decimal
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pha
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tya
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jsr c64.CHROUT
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pla
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jsr c64.CHROUT
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txa
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jsr c64.CHROUT
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plx
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rts
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}}
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}
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asmsub print_ub (ubyte value @ A) clobbers(A,Y) {
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; ---- print the ubyte in A in decimal form, without left padding 0s
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%asm {{
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phx
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jsr conv.ubyte2decimal
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_print_byte_digits
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pha
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cpy #'0'
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beq +
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tya
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jsr c64.CHROUT
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pla
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jsr c64.CHROUT
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jmp _ones
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+ pla
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cmp #'0'
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beq _ones
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jsr c64.CHROUT
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_ones txa
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jsr c64.CHROUT
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plx
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rts
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}}
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}
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asmsub print_b (byte value @ A) clobbers(A,Y) {
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; ---- print the byte in A in decimal form, without left padding 0s
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%asm {{
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phx
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pha
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cmp #0
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bpl +
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lda #'-'
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jsr c64.CHROUT
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+ pla
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jsr conv.byte2decimal
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jmp print_ub._print_byte_digits
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}}
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}
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asmsub print_ubhex (ubyte value @ A, ubyte prefix @ Pc) clobbers(A,Y) {
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; ---- print the ubyte in A in hex form (if Carry is set, a radix prefix '$' is printed as well)
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%asm {{
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phx
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bcc +
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pha
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lda #'$'
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jsr c64.CHROUT
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pla
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+ jsr conv.ubyte2hex
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jsr c64.CHROUT
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tya
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jsr c64.CHROUT
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plx
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rts
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}}
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}
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asmsub print_ubbin (ubyte value @ A, ubyte prefix @ Pc) clobbers(A,Y) {
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; ---- print the ubyte in A in binary form (if Carry is set, a radix prefix '%' is printed as well)
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%asm {{
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phx
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sta P8ZP_SCRATCH_B1
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bcc +
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lda #'%'
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jsr c64.CHROUT
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+ ldy #8
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- lda #'0'
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asl P8ZP_SCRATCH_B1
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bcc +
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lda #'1'
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+ jsr c64.CHROUT
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dey
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bne -
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plx
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rts
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}}
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}
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asmsub print_uwbin (uword value @ AY, ubyte prefix @ Pc) clobbers(A,Y) {
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; ---- print the uword in A/Y in binary form (if Carry is set, a radix prefix '%' is printed as well)
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%asm {{
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pha
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tya
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jsr print_ubbin
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pla
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clc
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jmp print_ubbin
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}}
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}
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asmsub print_uwhex (uword value @ AY, ubyte prefix @ Pc) clobbers(A,Y) {
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; ---- print the uword in A/Y in hexadecimal form (4 digits)
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; (if Carry is set, a radix prefix '$' is printed as well)
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%asm {{
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pha
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tya
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jsr print_ubhex
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pla
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clc
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jmp print_ubhex
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}}
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}
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asmsub print_uw0 (uword value @ AY) clobbers(A,Y) {
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; ---- print the uword in A/Y in decimal form, with left padding 0s (5 positions total)
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%asm {{
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phx
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jsr conv.uword2decimal
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ldy #0
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- lda conv.uword2decimal.decTenThousands,y
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beq +
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jsr c64.CHROUT
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iny
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bne -
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+ plx
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rts
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}}
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}
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asmsub print_uw (uword value @ AY) clobbers(A,Y) {
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; ---- print the uword in A/Y in decimal form, without left padding 0s
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%asm {{
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phx
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jsr conv.uword2decimal
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plx
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ldy #0
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- lda conv.uword2decimal.decTenThousands,y
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beq _allzero
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cmp #'0'
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bne _gotdigit
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iny
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bne -
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_gotdigit
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jsr c64.CHROUT
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iny
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lda conv.uword2decimal.decTenThousands,y
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bne _gotdigit
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rts
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_allzero
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lda #'0'
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jmp c64.CHROUT
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}}
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}
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asmsub print_w (word value @ AY) clobbers(A,Y) {
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; ---- print the (signed) word in A/Y in decimal form, without left padding 0's
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%asm {{
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cpy #0
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bpl +
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pha
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lda #'-'
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jsr c64.CHROUT
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tya
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eor #255
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tay
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pla
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eor #255
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clc
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adc #1
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bcc +
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iny
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+ jmp print_uw
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}}
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}
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asmsub input_chars (uword buffer @ AY) clobbers(A) -> ubyte @ Y {
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; ---- Input a string (max. 80 chars) from the keyboard. Returns length in Y. (string is terminated with a 0 byte as well)
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; It assumes the keyboard is selected as I/O channel!
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%asm {{
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sta P8ZP_SCRATCH_W1
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sty P8ZP_SCRATCH_W1+1
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ldy #0 ; char counter = 0
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- jsr c64.CHRIN
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cmp #$0d ; return (ascii 13) pressed?
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beq + ; yes, end.
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sta (P8ZP_SCRATCH_W1),y ; else store char in buffer
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iny
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bne -
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+ lda #0
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sta (P8ZP_SCRATCH_W1),y ; finish string with 0 byte
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rts
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}}
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}
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asmsub setchr (ubyte col @X, ubyte row @Y, ubyte character @A) clobbers(A) {
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; ---- sets the character in the screen matrix at the given position
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%asm {{
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pha
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txa
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asl a
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stz cx16.VERA_CTRL
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stz cx16.VERA_ADDR_H
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sta cx16.VERA_ADDR_L
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sty cx16.VERA_ADDR_M
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pla
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sta cx16.VERA_DATA0
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rts
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}}
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}
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asmsub getchr (ubyte col @A, ubyte row @Y) -> ubyte @ A {
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; ---- get the character in the screen matrix at the given location
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%asm {{
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asl a
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stz cx16.VERA_CTRL
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stz cx16.VERA_ADDR_H
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sta cx16.VERA_ADDR_L
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sty cx16.VERA_ADDR_M
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lda cx16.VERA_DATA0
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rts
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}}
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}
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asmsub setclr (ubyte col @X, ubyte row @Y, ubyte color @A) clobbers(A) {
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; ---- set the color in A on the screen matrix at the given position
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%asm {{
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pha
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txa
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asl a
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ina
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stz cx16.VERA_CTRL
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stz cx16.VERA_ADDR_H
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sta cx16.VERA_ADDR_L
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sty cx16.VERA_ADDR_M
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pla
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sta cx16.VERA_DATA0
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rts
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}}
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}
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asmsub getclr (ubyte col @A, ubyte row @Y) -> ubyte @ A {
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; ---- get the color in the screen color matrix at the given location
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%asm {{
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asl a
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ina
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stz cx16.VERA_CTRL
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stz cx16.VERA_ADDR_H
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sta cx16.VERA_ADDR_L
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sty cx16.VERA_ADDR_M
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lda cx16.VERA_DATA0
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rts
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}}
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}
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sub setcc (ubyte column, ubyte row, ubyte char, ubyte charcolor) {
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; ---- set char+color at the given position on the screen
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%asm {{
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phx
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lda column
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asl a
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tax
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ldy row
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lda charcolor
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and #$0f
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sta P8ZP_SCRATCH_B1
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stz cx16.VERA_CTRL
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stz cx16.VERA_ADDR_H
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stx cx16.VERA_ADDR_L
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sty cx16.VERA_ADDR_M
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lda char
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sta cx16.VERA_DATA0
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inx
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stz cx16.VERA_ADDR_H
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stx cx16.VERA_ADDR_L
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sty cx16.VERA_ADDR_M
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lda cx16.VERA_DATA0
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and #$f0
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ora P8ZP_SCRATCH_B1
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sta cx16.VERA_DATA0
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plx
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rts
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}}
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}
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asmsub plot (ubyte col @ Y, ubyte row @ A) clobbers(A) {
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; ---- safe wrapper around PLOT kernel routine, to save the X register.
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%asm {{
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phx
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tax
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clc
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jsr c64.PLOT
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plx
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rts
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}}
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}
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asmsub width() clobbers(X,Y) -> ubyte @A {
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; -- returns the text screen width (number of columns)
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%asm {{
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jsr c64.SCREEN
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txa
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rts
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}}
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}
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asmsub height() clobbers(X, Y) -> ubyte @A {
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; -- returns the text screen height (number of rows)
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%asm {{
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jsr c64.SCREEN
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tya
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rts
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}}
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}
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}
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