Siemens S7-300 MPI problems

[PLCDontUQuitOnMe]

Hi I've been struggling with trying to get a TP27 working with a 315-2DP. In my struggles I must have inadvertantly set something up incorrectly.

Now I cannot even get online with the PLC anymore. I keep seeing this error everywhere: "Online: The local MPI address for the programming device/PC is higher than the maximum node address or the wrong transmission rate or wrong interrupt vector is set."

I have checked all of the offline info and it seems fine. PG is MPI 0, TP is 1(although I don't think that's what it is in the actual TP, which i can't figure out how to manually change, but that's a different thread), CPU is 2, and CP is 3.

All MPI is set to 19.2 kbps, and so is the PC adapter.

When I view the online project, it looks exactly the same as the offline, but I can't change anything(not that I would want to I guess, even though it is giving that error).

Max node is set to 31 for MPI, and I haven't touched the interrupt settings(don't even know where they are in Simatic, but aware of them in Windows Control Panel)

I have even checked to Protool setup and it corresponds to the above info.

What am I missing? I'm seriously getting very frustrated and about to suplex my laptop.

 

[JesperMP]

Are you sure you have 19.2 k on the MPI side ?
19.2 k between PC and PC adapter is normal for the old slow PC adapter.
But for MPI, the most typical speed is 187.5 k.
And, newer PC adapters also support 38.4 k between PC and adapter. You may try to investigate that as well.

 

[PLCDontUQuitOnMe]

This PC adapter can run at 19.2 or 38.4, I put it down to 19.2 and configured that number everywhere to eliminate a high baud rate as a possible problem. I have noticed that the MPI network sometimes resets back to 187.5k. Maybe I should leave that as it is, and just make the adapter go at 19.2. I will reply back tomorrow after I test it out.

 

[JesperMP]

Yes. Leave it at 187.5k on the MPI side.

 

[tim2]

Leave the MPI network and the HMI terminal set up at 187.5k.

The 19.2k or 38.4k only applies to the speed of the connection from the PC to the PLC through the adapter, the reset of the network (the PLC to HMI connection) should be 187.5k.

 

[PLCDontUQuitOnMe]

I switched the PG to auto and that seems to have done the trick. I can get online now.

However I still can't download to the TP27. On the MPI download screen it says "MPI OP Station Address: 42" and "MPI Baudrate: 1.5 MBaud"

SO I'm assuming the OP is set for profibus, but I can't seem to connect to it. I configure everything properly, the correct node and everything, but I still get "No connection to the OP!"

What gives?

 

[PLCDontUQuitOnMe]

On the MPI Download screen on the TP it also says:

"Tel.: FF" and
"Download Address: FF"

What are these settings? What is the difference between the download address and the mpi op station address?