page-1983-101-timex-sinclair-programming-tricks

130 PRINT •BACKWARD:•140 FOR J=L TO 1 STEP -1150 PRINT A$(J);160 NEXT J170 IF INKEY$=•• THEN GOTO 170180 CLS190 GOTO 108 Drawing SketchesNow you can draw lines, rules, diagrams, maps, charts,boxes-anything you can imagine-on the face of yourTV set. Use the Computer keyboard as your penand its video output as your ink.Lines 120 to 150 accept your up, down, right, or leftcommands, as U, D, R, or L. No other letters will work.Line 200 draws your lines.Program Listing10 CLS20 LET X=3230 LET Y=2240 PLOT X,Y100 LET A$=INKEY$110 IF A$=•• THEN GOTO 100120 IF A$=•o• THEN LET Y=Y+l130 IF A$=•0° THEN LET Y=Y-1140 IF A$="R" THEN LET X=X+l150 IF A$="L" THEN LET X=X-1200 PLOT X,Y210 LET A$=••220 GOTO 10023