Identifying Bad Tags Using 'FailOnBadData'

A bad tag is defined as any tag that does not exist within the ControlLogix system, which is something that can occur when developing large systems.

During the commissioning phase a project, you need to clearly identify any blocks of data that include bad tags. The FailOnBadData parameter helps achieve this by allowing you to run your project in two different modes:

• When FailOnBadData is off, the ABCLX driver will not return "#COM" for a block of data if at least one valid value is in the read block.

• If FailOnBadData is on, if any tag values in a blocked read are missing or inaccessible, the whole block is rejected and will return "#COM". This highlights the presence of bad tags and identifies where corrective action is required. This default behavior is the preferred mode of operation when you are running a project.

By default FailOnBadData is on (1). See ABCLX Specific Parameters.

Example

Display reads that include a bad tag in the block with #COM:

[ABCLX]
FailOnBadData=1

Ignore any bad tags in the block reads and just show 0 for those tags:

[ABCLX]
FailOnBadData=0