HP·38E/38C - Slide Rule Museum

106 Decisions
As you work through this handbook, you will become more familiar
with flowcharts. Use the flowcharts that illustrate the examples and
problems to help you understand the many features of the calculator,
and draw your own flowcharts to help you create, edit, eliminate errors
in, and document your programs.
Branching
Although program execution is normally sequential, with one line
executed after another, execution can be transferred or "branched"
to any line in program memory. The " branch" can be made unconditionally
or it can be made dependent on the outcome of a comparison
of data values.
Unconditional Branching and Looping
You have seen how I GTO I 0 is used in program mode to help you
display any line in program memory. You can also use the I GTO I
instruction as part of a program, to branch program execution to the
line number specified. It can tell the calculator to execute line 00 next,
as we have already seen, or to execute any other line in program memory.
By using a I GTO I instruction in your program, you can transfer execution
to any part of the program that you choose.
02-
03-
09-25 7 03 ([[) I GTO I 03)
Execution branches to line 03.