1width=300
    2height=100
   10moveabs=4
   20linerel=1
   30TRIrel=linerel+80
   40moverel=0
   50DIM ox 3,oy 3
   60DIM Code 511
   70PROCassemble
   80PROC_init
   90PROC_main
  100END
  110DEFPROC_cursor
  120   MOVE OX,OY
  130   VDU 128
  140ENDPROC
  150 
  160DEFPROC_init
  170OX = 0:OY = 0:X = 0:Y = 0:!ox=OX:!oy=OY
  180MODE1
  190   VDU 5,18,3,1,23,128,0,24,60,126,24,24,24,0
  200ENDPROC
  210 
  220DEFPROC_track
  230   X=ADVAL(1): Y=ADVAL(2)
  240   X = (1024 - (X DIV 64)) * 1280 DIV 1024: Y = Y DIV 64
  250   X = X DIV 16 * 16: Y = Y DIV 20 * 20
  260ENDPROC
  270 
  280DEFPROC_main
  290   REPEAT
  300      A%=USR(cursor)
  310      !ox = X:!oy = Y
  320      REPEAT PROC_track: UNTIL X<>!ox OR Y<>!oy
  330      IF (ADVAL(0) AND 1) <> 0 THEN A%=USR(cursor)
  340      A%=USR(cursor)
  350      !ox = X:!oy = Y
  360   UNTIL FALSE
  370ENDPROC
  380DEFPROCassemble
  390FOR Pass=0 TO 2 STEP 2
  400OSWRCH=&FFEE
  410P%=Code
  420[OPT Pass
  430.cursor
  440]
  450PROCplot(moveabs):PROCvar(ox):PROCvar(oy)
  460PROCplot(linerel):PROCconst(24):PROCconst(0)
  461PROCplot(moverel):PROCconst(width-48):PROCconst(0)
  462PROCplot(linerel):PROCconst(24):PROCconst(0)
  470PROCplot(linerel):PROCconst(0):PROCconst(-24)
  471PROCplot(moverel):PROCconst(0):PROCconst(-(height-48))
  472PROCplot(linerel):PROCconst(0):PROCconst(-24)
  480PROCplot(linerel):PROCconst(-24):PROCconst(0)
  481PROCplot(moverel):PROCconst(-(width-48)):PROCconst(0)
  482PROCplot(linerel):PROCconst(-24):PROCconst(0)
  490PROCplot(linerel):PROCconst(0):PROCconst(24)
  491PROCplot(moverel):PROCconst(0):PROCconst(height-48)
  492PROCplot(linerel):PROCconst(0):PROCconst(24)
  500   [OPT Pass:Rts:]
  510NEXT Pass
  520ENDPROC
  530 
  540DEFPROCvar(Addr)
  550[OPT Pass
  560   Lda Addr
  570   Jsr OSWRCH
  580   Lda Addr+1
  590   Jsr OSWRCH
  600]
  610ENDPROC
  620 
  630DEFPROCvdu(C%)
  640[OPT Pass
  650   Lda #C%
  660   Jsr OSWRCH
  670]
  680ENDPROC
  690 
  700DEFPROCplot(plotcode)
  710   PROCvdu(25)
  720   PROCvdu(plotcode)
  730ENDPROC
  740 
  750DEFPROCconst(X%)
  760X% = (X% AND &FFFF)
  770   PROCvdu(X% MOD 256)
  780   PROCvdu(X% DIV 256)
  790ENDPROC