High latency network (modems) may cause SNAP PAC controller to I/O unit communication problems

Applies To:

SNAP-PAC-S1
SNAP-PAC-S2
SNAP-PAC-R1
SNAP-PAC-R2
SNAP-PAC-S1-W
SNAP-PAC-S2-W
SNAP-PAC-R1-W
SNAP-PAC-R2-W

Versions Affected:

Problem was discovered in version: R8.5a
Problem is fixed in version: R8.5c

Resolved In Version:

Problem is fixed in version: R8.5c

Symptoms:

A SNAP-PAC control engine may have trouble communicating with an Ethernet brain over a wireless network device with a high latency response time (such as a cellular or radio modem). An error message is not posted to indicate there was a problem communicating to the I/O unit. The data received contained all zeroes.

Here's an example of a SNAP PAC Ethernet system over a wireless device with a high latency response time:

A SNAP PAC control engine is communicating via Ethernet to a radio modem. At a remote location, a radio modem is communicating over Ethernet to a SNAP PAC Ethernet brain.

Questions?

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

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