Thelen Posted March 3, 2002 Share Posted March 3, 2002 i wanted to try some programming on the atari 2600 but I don't understand this : my intention was to see at screen line 10 byte number 3 of pfdata1, but i get it over the whole screen i don't see what i do wrong, I compare Y with 10, so only if Y=10 then the pfdata byte 3 will be drawn at line 10 i thought. LDY #191 ScanLoop STA WSYNC CPY #10 ; compare y with 10 BNE nop0 ; not 10 ? goto nop0 LDX #3 LDA PFData1,x ;byte 3 from pfdata STA PF1 LDA #$FA STA COLUP0 ;color FA nop0 DEY BNE ScanLoop thanks, TheleN Quote Link to comment Share on other sites More sharing options...
DanBoris Posted March 4, 2002 Share Posted March 4, 2002 Two possible problems. First are you clearing PF1 at the start of the frame? If not then it will always display the same pattern. Also, if you want to only display on that single line you will have to clear PF1 after that line. Dan Quote Link to comment Share on other sites More sharing options...
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