ProSoft Technology MVI56-AFC User Manual
Page 262
Diagnostics and Troubleshooting
MVI56-AFC ♦ ControlLogix Platform
User Manual
Liquid and Gas Flow Computer
Page 262 of 316
ProSoft Technology, Inc.
February 25, 2011
13.4 Checksum Alarms
A checksum alarm indicates a checksum verification failure during power-up.
Non-volatile information is kept in battery-backed RAM. It is partitioned into
several blocks, each of which contains a checksum, and when the information is
changed the checksum is updated also. During power-up, the checksum is
verified, and upon failure the alarm bit is latched and the checksum corrected.
The alarm bit remains latched, even through subsequent power cycles, until it is
explicitly cleared from an external source such as the AFC Manager. Refer to the
AFC Manager User Manual for more information about this feature.