Communication to mistic I/O units erroneously disabled by error in PAC Control

Applies To:

Versions Affected:

Problem affects versions: Firmware R9.3e and lower
Problem is fixed in version: Firmware R9.4a

Resolved In Version:

Problem is fixed in version: Firmware R9.4a

Symptoms:

This problem applies only to mistic I/O units connected to SNAP PAC controllers running PAC Control.

If an I/O command results in an error, communication to the mistic I/O unit may be disabled, even if the error is not related to communications.

Workaround:

As one example, if you're using the TPO feature on a digital output, you must set the TPO Period before setting the TPO Percent, or else an error will occur. If you re-enable communication to the I/O unit that has the digital TPO output point, and then set the TPO Percent before setting the TPO Period, communication to that I/O unit will become disabled.

Here's how you can work around it:

Use a "gateway" variable around any usage of the Set TPO percent command.
When your I/O enabler chart detects that the I/O unit has been disabled, it must:

Set the gateway variable to a value that lets other charts know not to set the TPO percentage
Enable the I/O unit
Set the TPO Period
Set the gateway variable to a value that lets other charts know that it's ok to use the command Set TPO Percent

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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