Commodore 128D - Page 305

RETURN
RUN
This example traps a "division by zero error" in line 20 if 0 is entered
in line 10. If zero is entered, the program goes to line 100, where you
are asked to input another number besides 0. Line 110 returns to line
20 to complete the calculation. Line 50 asks if you want to repeat the
program again. If ytiu do, press the Y key.
—Return from subroutine
RETURN
This statement is always paired with the GOSUB statement. When
the program encounters a RETURN statement, it goes to the state
ment immediately following the last GOSUB command executed. If
no GOSUB was previously issued, then a RETURN WITHOUT
GOSUB ERROR message is displayed and the program stops. All
subroutines end with a RETURN statement. See COLLISION.
EXAMPLE:
10 PRINT "ENTER SUBROUTINE"
20 GOSUB 100
30 PRINT "END OF SUBROUTINE"
90 STOP
100 PRINT "SUBROUTINE 1"
110 RETURN
This example calls the subroutine at line 100 which prints the mes
sage "SUBROUTINE 1" and RETURNS to line 30, the rest of the
program.
—Execute BASIC program
1) RUN [line #]
2) RUN "filename" [,Ddrlve numberRON | ,>Udevlce
number]
Once a program has been typed into memory or LOADed, the RUN
command executes it. RUN clears all variables in the program
before starting program execution. If there is a number following the
RUN command, execution starts at that line number. If there is a
filename following the RUN command, the named file is loaded from
the disk drive and RUN, with no further action required of the user.
RUN may be used within a program. The default drive number is 0
and default device number is 8.
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BASIC 7.0 ENCYCLOPEDIA—Basic Commands and Statements