One of the biggest problems in typing in magazine listings is to
make sure that you have typed in the program correctly. Many readers
have asked if there is a solution to this problem but there is no
magic answer, a lot of care and hard work are involved even if you use
a utility such as TYPO.
TYPO is used by ANTIC magazine and was first published by them in
August 1982. It is reprinted here with their permission. In future we
will include a TYPO chart with all but the shortest listings in PAGE 6
which will hopefully help you to correct those bugs.
TYPO will produce a chart which you then compare with the chart
printed in the magazine. BE WARNED though, TYPO is very fussy and you
must type in the listing exactly as shown-every REM, space and comma,
lower case etc. must be the same. TYPO will help you get an identical
listing but you still have to search out and correct mistakes. At
least the line numbers will be narrowed down.
Here's how to type in the listing. First type in the program
exactly as shown (including the REM) and LIST it to disk (LIST"D:TYPO")
or cassette (LIST"C:"). Next type NEW and then ENTER the
program again (ENTER"D:TYPO") or (ENTER"C:"). Now
change the number 32000 in lines 32180 and 32200 to 32500 and RUN the
program. Compare the chart with the printed chart. If they are
different, check through the listing, make any corrections and go
through the procedure again. When the charts agree, change the numbers
32500 back to 32000 in the above lines and LIST the program to a new
disk or tape. This is your master TYPO program.
TYPO IN USE
Follow this procedure exactly:
1. Type in a listing from the magazine.
2. LIST the program to disk (LIST"D: NAME" or cassette (LIST"C:").
3. Type NEW.
4. ENTER the program (ENTER"D: NAME" or (ENTER"C:')
5. Change to the disk or cassette with TYPO on and enter TYPO (ENTER"D:TYPO")
or (ENTER"C:").
6. Type GOTO 32000. Type S for output to the screen or P for
printer. The program will produce a chart. If the chart agrees with
the one in the magazine, you have an identical listing. Well done!
7. The chart doesn't agree, does it! Examine the lines which do not
agree and correct any errors.
8. IF THE VARIABLE CHECKSUM AGREES go to step 6.
9. If the variable checksum does not agree, you MUST go to step 2
but you can skip step 5 as TYPO will already be on the end of your
program.
HINTS ON FINDING ERRORS
If the variable checksum does not agree, you have either typed in
lines in wrong order or mispelled a variable name. See the next
paragraph to narrow down the area of error, and make the corrections.
You must now go through the LIST/NEW/ENTER procedure again to put the
variable name table in correct order.
The Length shown is the number of bytes within the program lines
shown. The two letter code is essentially a checksum of
"length" bytes within that range. If the length is correct
and the code is wrong, you have made a spelling or punctuation error.
Be careful though, as all keywords and operators are stored as one
byte and the length might stay the same even though you type COLOR
instead of SETCOLOR. If the length disagrees, you have added or
deleted characters or spaces. If nothing obvious shows, pay special
attention to REM statements, every space must be there.
TYPO will get you an identical listing (eventually) but don't think
it will do it automatically. You still have to search for errors and
correct them but at least you will have an idea where they are.
TYPO is Copyright 1982 ANTIC magazine. Reproduced with
permission.
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