Denso BHT-BASIC 100 SERIES, Programmer'S Manual

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Syntax:
GOSUB label
Description:
GOSUB calls a subroutine specified by label .
• Within the subroutine itself, you use a RETURN statement which indicates the log-
ical end of the subroutine and returns control to the statement just after the
GOSUB that called the subroutine.
• You may call a subroutine any number of times as long as the Interpreter allows
the nest level and other conditions.
• Subroutines can appear anywhere in a source program. However, you should
separate subroutines from the main program by any means such as by placing
subroutines immediately following the END or GOTO statement, in order to pre-
vent the main part of the program from falling into those subroutines.
• A subroutine can call other subroutines. You can nest GOSUB statements to a
maximum of 10 levels.
• When using the GOSUB statement together with block-structured statements
( DEF FN
...
END DEF , FOR
...
NEXT , FUNCTION
...
END FUNCTION , IF
...
THEN
...
ELSE
...
END IF , SELECT
...
CASE
...
END SELECT , SUB
...
END SUB , and
WHILE
...
WEND ), you can nest them to a maximum of 30 levels.
Syntax errors:
Flow control statement
GOSUB
Branches to a subroutine.
Error code and message Meaning
error 71: Syntax error • label has not been defined.
• label is missing.