Can't read or write to analog points when there is an open comm handle to a missing serial communication module

Applies To:

SNAP-PAC-R1
SNAP-PAC-R1-FM
SNAP-PAC-R1-W
SNAP-PAC-R1-B
SNAP-PAC-R2
SNAP-PAC-R2-FM
SNAP-PAC-R2-W
SNAP-PAC-EB2
SNAP-PAC-EB2-FM
SNAP-PAC-EB2-W

Versions Affected:

Versions affected: I/O coprocessor firmware lower than R3.0a
Problem is fixed in version: I/O coprocessor firmware R3.0a

Resolved In Version:

Problem is fixed in version: I/O coprocessor firmware R3.0a

Symptoms:

If a PAC Control strategy has an open communication handle to a port whose associated rack position is empty:

Any writes to analog points will fail without logging or reporting an error.
Any reads of analog input points will return a value of -1.#QNAN.

NOTE: This is a coprocessor issue.

Workaround:

Make sure that communication handles are properly configured, and don't remove SNAP-SCM modules from a rack while a strategy that uses the modules is running.

Resolution:

Opto 22 has resolved this issue.

Questions?

Contact: Opto 22 Product Support.
Phone: 800-835-6786 or 951-695-3080
Email: support@opto22.com

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