10 TB=4096
100 FORAN=0TO2*(null)STEP2*(null)/256
200 X=SIN(AN)*5632
300 Y=XAND255:POKETB,Y:POKETB+256,Y
400 Y=X/256:IFX<0THENY=Y+256
500 POKETB+512,Y:POKETB+768,Y
600 TB=TB+1:NEXT