GOSUB and RETURN

A GOSUB transfers program execution to the block number specified in the GOSUB statement.

Execution will continue until a block containing a RETURN statement is encountered. The

RETURN will transfer control back to the block immediately following the GOSUB statement.

To use a GOSUB statement, the called block number must be part of the same program.

Generally the subroutines are at the end of the main program.

The GOSUB format is as follows.

GOSUB #### L###

Line # Loop Count

(optional)

If the L is omitted the GOSUB routine will be executed once.

N4 GOSUB 100 Main Program

N90 M30

N100

N101

. Subroutine

N200

N201 RETURN

N202

When the GOSUB is executed in N4 the program will jump to N100 and start executing until

N201 is reached. At N201 control will transfer to N5 and lines N5 thru N90 will be executed.

The M30 will terminate the main program and keep lines 100 thru 202 from being executed

again. Note: subroutine nesting is allowed to 50 levels deep.