KB89623
Published: March 9, 2022
Revision: 2.0

PAC Control command "Is I/O Unit Ready?" may cause chart to freeze or host port to lose communication


Applies To:

  • SNAP-PAC-S1, SNAP-PAC-S1-FM, SNAP-PAC-S1-W
  • SNAP-PAC-S2, SNAP-PAC-S2-W
  • 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

Versions Affected:

R9.5f to R10.4c

Resolved In Version:

R10.4d


Symptoms:

When using the Is I/O Unit Ready? command on a serial I/O unit, the command may freeze:

  • In Debug mode, if the chart was in auto-step mode through the charts, the block with the instruction remains highlighted.
  • If you try to stop the strategy, host port communication is lost.
With either scenario, you have to cycle power to the controller to clear the issue.

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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