Confirming SynqNet Control Latency

It is a recommended design practice for all SynqNet systems that you check that the node control latency is as expected.

Baseline Control Latency

After tuning your system, the scheduled control latency should be noted and then checked by the motion application after each SynqNet initialization.

In MPI 03.03.00 and earlier, a single control latency for all nodes can be read from
MPISynqNetTiming.controlLatency.total.

In MPI 03.04.00 and later releases, the scheduled control latency is reported as MPISynqNetTiming.node[n].controlLatency value for every node n on the SynqNet network.

Checking the Control Latency

Use one of the following two ways to ensure that the node control latency is as expected.

Automatic Checking

Automatic checking by the MPI is performed if a value for MPISqNodeConfigControlLatency.maximum is non-zero.

See MPISqNodeConfigControlLatency for more info.
NOTE: This value needs to be set for each node.

If MPISqNodeConfigControlLatency.maximum value is non-zero, and the scheduled control latency differs, an MPISynqNetMessageNODE_LATENCY_EXCEEDED error will be returned from mpiControlInit(...) and/or mpiSynqNetInit(...).

See Also:

Node Control Latency | Cable Length Discovery Uncertainty Factor