Rayback

Nice,i will try it

Thank you for your tips,i tried to integrate the code with what you said, and the sprite now works, even if (i don't know why) it appears in different locations on the screen every time i open the rom,and using the debugger i have found that is like the processor adds the wrong data from the table

Thanks for your answer,im going to install this emulator for sure,seems more advanced

up

further more the code is correctly idented,not like the post

Hi guys, i am new at programming the 6502 processor ( i would like to develop on atari 2600),so im trying to practice up by writing some random stuff. The question for you,expert programmers is the following one: i have written a code,and i tried to add a player on the screen, also i used some variables for setting the y pos and the lines where the sprite can appear. but,anyway,the sprite doesn't work,so i wonder if there is any mistake in the source code and in the opcodes usage. ( i use z26 as emulator) here is the code i made processor 6502 include "vcs.h" include "macro.h" SEG ORG $F000 pline = $81 ypos = $80 ; initializing, cleaning ram and tia registers ldx #$FF lda #0 clea sta $00,x dex bne clea ; setting color for player lda #$18 sta COLUP0 ; setting y pos for player 0 lda #80 sta ypos Reset StartOfFrame ; vsync lda #2 sta VSYNC sta VBLANK sta WSYNC sta WSYNC sta WSYNC lda #0 sta VSYNC ; 37 lines of vetical blank lda #43 sta TIM64T vb sta WSYNC lda INTIM bne vb lda #0 sta VBLANK ; 192 lines of picture ldy #3 lda #$70 sta COLUBK lda #$1E sta COLUPF lda #%11000000 light sta PF0 nop nop lda #%00111000 sta PF1 sta PF2 sta WSYNC dey bne light ; void ldy #15 lda #0 sta PF1 sta PF0 sta PF2 void sta WSYNC dey bne void ; palace ldy #174 lda #$08 sta COLUPF pic sta WSYNC lda #%11111111 sta PF1 sta PF0 sta PF2 checkpl cpy ypos bne skip lda #7 sta pline skip draw ldx pline beq final lda Frame0,X sta GRP0 dec pline final dey bne pic ; over scan ldx #0 lda #2 over sta VBLANK sta WSYNC inx cpx #30 bne over jmp StartOfFrame Frame0 .byte #%10000001 .byte #%11000011 .byte #%01111110 .byte #%00111100 .byte #%00111100 .byte #%11111111 .byte #%10111101 .byte #%00111100 ;finishing org $FFFC InterruptVectors word. Reset word. Reset END