Radio Shack TRS-80 PC-3 Owner's Manual page 207

You are running a BASIC program and it displays
something, and stops
You enter a calculation and it is displayed in BASIC
statement format (colon after the first number)
You get no response from any keys.
1. Push
(ENTER) .
1. Switch from the PROgram into the R UN mode for
calculations.
1. Hold down any key and push RESET.
2. If you get no response from any key, even when the above
operation is performed, push the RESET without any key.
(With this operation, the program, data, and all reserved
contents are cleared.)
BASIC Debugging
A newly entered BASIC program may not always work for the first time. Even if you are simply keying in a program that you
know is correct, such as those provided in this manual, it is usual to make at least one typing error. If it is a new program of any
length, it will probably contain at least one logic error, as well. Following are some general hints on how to find and correct your
errors.
You run your program and get an error message:
1. Go back to the PROgram mode and use the
CTI
or the
([J
keys to recall the line with the error. The cursor will be
positioned at the place in the line where the PC-3 Computer got confused.
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