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Commands - 109

RETURN

Statement

SYNTAX: RETURN [line/label]

RETURN ITR number

PURPOSE: To resume execution after a GOSUB, interrupt, multitasking or communications call. The RETURN

ITR reenables the interru pt.

REMARK S: RETURN is used as a return from a GOSUB call. Program execution continues at the statement

following the GO SUB.

number is 0 or 1, or as limited by your hardware. It is the interrupt number that the subroutine

declared by ON ITR n declared.

If the optional line/ label is specified, the progr am will branch to the specified line/ label.

RETURN ITR is used as a return fro m an ON ITR GOSU B declaration. In this case the return is to

the next statement where the interrupt occurred. The hardware interrupt is reenabled. If ITR

number is left off, the return is still to the next statement where the interrupt occurred. However,

interrupt number is disabled until a RETURN ITR number is executed or ON IT R GO SUB is

declared again. This is useful when you want to recognize an interrupt once and enable it again at

some later time.

RELATED: GOSUB, ON ITR

EXAMPLE: 10 ON ITR 0 GOSUB 40

20 A=23 : 'This is a dummy loop

30 GOTO 20

40 PRINT "Interrupt"

50 RETURN ITR 0

ERROR: < RETURN w/o GOSUB> – if no corresponding GOSUB

< Can’t compile> – if line/label does not exist

< Data out of range> - if number is not 0 or 1 when used with ITR

< Expected (> - if number is missing when used with an ITR

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Remote-processing CAMBASIC Manual do Utilizador Página 142