Radio Shack TRS-80 PC-3

Since this is the only line of the program, the computer will stop executing at this point. Press (ENTER) to get out of the program
and reenter
RUN if you wish to execute the program again.
Example 2 - Editing a Program
Suppose you wanted to change the message that you program was displaying; that is, you wanted to edit your program. With a
single line program
you could just retype the entry, but as you develop move complex programs editing becomes a very important
component of your programming. Let's edit the program you have just written.
Are you still in the RUN mode? If so, switch back to the PROgram mode.
You need to recall your program in order to edit it. Use the Up Arrow (t) to recall your program. If your program was com-
pletely executed, the ([) will recall the last line of the program. If there was an error in the program, or if you used the BREAK
((BREAK)) key to stop execution, the ([) will recall the line in which the error or BR EAK occurred. To make changes in your
program, use the ([) to move up in your program (recall the previous line) and the CD to move down in your program (display
the
next line). If held down, the ([) and the CD will scroll verticaly; that is, they will display each line moving up or down in
your program.
You will remember that to move the cursor within a line you use the ~ (right arrow) and ~ (left arrow). Using the CB ,
position the cursor over the first character you with to change:
Input
t
Display
1 0: PR I N T II H ELL all
63