Run/Idle indication for PROFIBUS/PROFINET?

I'm more familiar with Rockwell than I am Siemens - as this question I'm sure will demonstrate.

For Ethernet/IP and ControlNet networks, there can be a run/idle header to and from each device on the network to indicate the run state of the PLC and the run state of the device.

Does this same thing exist for PROFIBUS? And while we're at it, how about PROFINET? Maybe it's called something different (like MCR)?

Thanks in advance for any responses!

Yes, Profinet has status information in the data that lists the status (run/stop/error/etc) of the communication partners. I'm pretty sure that Profibus has this data as well, although I've never dissected a Profibus packet before. I do know that you can get the diagnostic data from PLCs acting as Profibus masters. However, how the device presents this data to you depends on the device.

Some IO nodes react when the PLC goes into stop, some have no errors.

In the S7-300 & 400, it creates events (via error OBs) any time the system detects an error (such as loss of communication to IO). You can also view the current status of the HW and Network by reading different System Status Lists (something like a GSV on the Rockwell side). If you use the Report System Error tool, it will also automatically generate HMI alarm messages for most HW related errors.

In the newer 1500s, the HMI alarm messages are generated automatically, no extra effort needed. The event based error handling via error OBs still exists. If you want to read the current status of a module or network there are a few instructions like Get_Diag and DeviceStates.

I'm not sure how other Profinet PLCs do their diagnostics.

Profibus is very similar to Profinet (or Profinet is similar to Profibus).
The Profibus master can send event telegrams when his operating-state has changed, as a broadcast to all slaves. Also there is a watchdog timeout when more that n (usually 3) telegrams of a bus cycle got lost. On a Siemens S7 the corresponding error OBs are called.

Very informative website about Profibus details (Profinet only in german):
http://www.profibus.felser.ch/en/

Thank you mk42 and Thomas_v2 for your responses.

I knew that there was something since the PLC would indicate with LED's when a device o one the bus (PROFIBUS or PROFINET) was offline. But I wasn't sure of the details.

I did find a useful article from ACROMAG that explains this pretty well. Here's a link for anyone that is interested: http://www.automation.com/library/articles-white-papers/fieldbus-serial-bus-io-networks/introduction-to-profibus-dp

Of course, that's PROFIBUS. I'll keep looking for PROFINET, although I would think that it should be pretty similar.

If you want to learn more about Profinet, PI is a great place to start. They are the Profinet/bus equivelent of the ODVA.

They have day long events that they do every year all over the country. If you're still in Columbus, OH, the next event near you is probably in Cleve, in June.

http://us.profinet.com/training/one-day-training/

For info sooner, they also have a number of webinars available.

http://us.profinet.com/training/webinars/

If you prefer reading (and don't mind a fair amount of scrolling), see the link below for an overview of a lot of the different technologies involved.
http://us.profinet.com/technology/profinet/

They probably have similar info available for Profibus, but Profinet is really where the future is, and what they are pushing.