base:realtime_8x_char_zoom
realtime_8x_char_zoom
; charzoomer 8x ; by Raf/Vulture Design ; June 2007 ; ; made in DASM 2.20 in mind, ; probably will work every ; assembler around. ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; *= $1000 ; text screen address screen_pos_lo = $10 screen_pos_hi = $11 ; font sddress font_addr_lo = $12 font_addr_hi = $13 ;helper variable fontlineoffs = $14 ; screen position to place char at lda #$00 sta screen_pos_lo lda #$04 sta screen_pos_hi ; font position addy, ; add (8*char_id) to select character you want to display ; this code is meant to be ass small as possible so no ; exact address is calculated , I don't need that in my ; program by the way lda #$00 sta font_addr_lo lda #$20 sta font_addr_hi ; font-line offset lda #0 sta fontlineoffs _begin ldy fontlineoffs LDA (font_addr_lo),y ;linia znaku LDY #7 _shift LSR ; shift one bit and see if it is 1 or 0 tax BCS _c_1 _c_0 LDA #32 ; 0 STA (screen_pos_lo),y jmp __1 _c_1 LDA #160 ; 1 STA (screen_pos_lo),y __1 txa DEY BPL _shift ; did we shift every bit already? lda screen_pos_lo ; add 40 (go down one pixel) clc adc #40 sta screen_pos_lo bcc __2 inc screen_pos_hi __2 inc fontlineoffs lda fontlineoffs cmp #8 ; DID WE PUT EVERY LINE OF CHAR? bmi _begin RTS *= $2000 .incprg font.prg ; any standard font
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base/realtime_8x_char_zoom.txt · Last modified: 2015-04-17 04:33 by 127.0.0.1