Commodore PET User Manual page 248

position. Make the proper changes. and the program should look like this:
5 F'RIHT":'J";
10 PRINT"r".; : GOSLIB 100
15 FOR 1=1 TO 5:PRINT"-"; : GOSLIB 100:NEXT 1
213 piu NT"
'm"; :
GOSLIB 11313
25 FOF: 1=1 TO 5: PRINT"
lm".; :
GOSLIB 1130: NEXT 1
30 PR 1NT" -1.1"; : GOSLIB 100
35 FOR 1=1 TO 5:PRINT"-I.I"; : GOSLIB 100:NEXT 1
413 PR 1NT" un"; : GOSLIB 1013
45 FOR 1=1 TO 5: F'RINT"I ln"; : GOSLIB 1(113: NEXT 1
513 EHD
11313 FOR J=l TO le:NEXT J:RETLIRN
Now try another trial run. Your picture should look like this:
1
F:EAD'r'.
F
1
1
Vou should have been able ta watch the PET slowly sketch the square on
the screen in a clockwise direction. Remember. vou may change the print speed
by changing the Ta index value for variable
J
in the time delay loop.
One last problem: How to avoid destroying the square with the READY
message.
When drawing the square is completed. the cursor is on line 2; when the
programs ends. the READY message is printed on the next line. which happens to
be within the square. Therefore. before ending the program. vou must compen-
sate for this by moving the cursor below the square; the READY message will be
written underneath the square and not across it. This is done by printing several
CURSOR DOWNs before the END statement.
50
PRItH"~":END
This will move the cursor down below the square and the square will not be
destroyed:
READ'.,'.
~
235