*= $1000
SCREEN   = $0404
         LDX #$1F
LOOP     TXA
         STA SCREEN,X
         CLC
         ADC #$20
         STA SCREEN+40,X
         ADC #$20
         STA SCREEN+80,X
         ADC #$20
         STA SCREEN+120,X
         ADC #$20
         STA SCREEN+160,X
         ADC #$20
         STA SCREEN+200,X
         ADC #$20
         STA SCREEN+240,X
         ADC #$20
         STA SCREEN+280,X
         ADC #$20
         DEX
         BPL LOOP
         RTS