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Disabling Address Block Deactivation for Modbus Ethernet or Modbus RTU Drivers

Whenever we have a shutdown or disconnect one of our devices the blocks of addresses we are accessing are being deactivated.  We are getting the following error:  "Bad address in block."

Is there any way to prevent the addresses we are accessing from being deactivated? 
Is there any way to allow me to force a deactivated block to be re-scanned?

There are two parts to this answer.

1. Configuring the driver to not deactivate blocks

In the Modbus Ethernet and Modbus RTU drivers (part of the TOP Server Modbus Suite), there are settings that may be configured a per device level to have the driver NOT deactivate blocks when an illegal address is reported within a block.

Clearing this checkbox will keep TOP Server from deactivating the tags/blocks and they are invalidated only, but still remain in the scan cycle, which should resolve the problem of tags being deactivated.

2630 - ModbusTCPDeactivate 2630 - ModbusRTUDeactivate
Modbus TCP/IP Ethernet driver Modbus RTU Serial driver

2. Forcing a block to re-scan without restarting the TOP Server or the client.

This is useful if you choose to let the driver de-activate tags on illegal address exception. See this FAQ for How to force a deactivated block to scan again.