“Retain-Persistent” NV Storage

Description

The P2CDS-622 holds the “Retain-Persistent” data type values in Battery-Backed SRAM, but does NOT write these variables into the Flash memory on a system power down.

If the Battery dies, all “Retain-Persistent” data will be lost.

Workaround

The user needs to ensure that the battery voltage is never allowed to go below its operating threshold.

There is a low battery warning in the CODESYS IDE that can be used to monitor the batter voltage. If removed, there is a minimum of 8 hours of “Super-Cap” emergency energy storage to hold the “Retain-Persistent” data.

Future Resolution

This issue will not be resolved.