Syserror – Rockwell Automation 1398-PDM-xxx IQ Master Version 3.2.4 for IA-2000 and IQ-5000 Positioning Drive Modules, IQ-55 User Manual

Page 293

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Language Reference • Reference

271

Publication 1398-PM601A-EN-P — October 2000

WORDS

SUB

Subroutine

Program Structure

Purpose

Mark the beginning of a subroutine and assign a name (up to eight characters) to the
subroutine. Subroutines must end with a RETURN statement. Subroutines cannot be
nested-that is, another subroutine cannot be called from within a subroutine. Program
flow must return from the present subroutine before calling another subroutine.

Syntax

SUB name

name

Subroutine names can be up to 32 characters long. Names cannot
be keywords of reserved words. They must begin with a letter and
contain only alphanumeric characters and underscores ( _ ).

Remarks

Subroutines should be located at the end of program after all of the statements of the
main program. An END statement should follow the RETURN of the last subroutine
in a program. Subroutines of one program are not accessible to another program.

See Also

RETURN, CALL

Example

SUB MySub

... Statements

RETURN

SYSERROR

Cause System Error

System

Purpose

Used to cause a system error. If set to a number, this will cause a system fault.

Syntax

SYSERROR= value

value

Value can be a constant, a nonvolatile flag Gn, a volatile Vn, or
another system variable.

Remarks

Refer to the Appendix “Error Messages” on page 418 for a list of errors.

See Also

FLAG, ENUM, WFLAG, WNUM, SYSWARN

Example

SYSERROR = 35

;will cause an ’Excessive Speed’ fault.

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