Knowledge Base / Protocols / PROFIBUS

How can I monitor module and slave status with the MVI56-PDPV1 and other PDPMV1 PROFIBUS master modules?

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The PDPMV1 operating state is stored in the MVIxxPDPMV1.Status.Fieldbus.FB_op_state tag:

 00 = Offline
 40 = Stop
 80 = Clear
 C0 = Operate

To determine slave status, the MVIxxPDPMV1.Status.Fieldbus.FB_Slave_Data_xfer array contains a bitmap of all the PROFIBUS slaves currently in communication with the PDPMV1 master.  The data type is SINTs, so each element in this array contains bits representing 8 PROFIBUS addresses.

For example, if bits 0 and 3 are set in MVIxxPDPMV1.Status.Fieldbus.FB_Slave_Data_xfer[0], slave addresses 0 and 3 are communicating successfully.  Slave_Data_xfer[1] would contain the booleans representing addresses 8-15,  Slave_Data_xfer[2] would contain the status bits for addresses 16-23, etc. A simple XIC or other RSLogix  function can be used to monitor the communication status of any slave attached to the PDPMV1 master.

Note that with the MVI56-PDPMV1 using the Legacy AOI and with the MVI69-PDPMV1 these status tags are continually updated automatically.  If using the MVI56-PDPMV1 with the Flex AOI, the toggling the MVI56PDPMV1.Command.GetStatus tag is required to trigger an update for this or any other status information.