M40 Profinet module: Problem with unused OE,WE & CS pins

Anybus Support Embedded
#1

Hi support team,
I had some hardware problems with a M40 Profinet-IRT module. I designed the hardware transport provider based on the “SPI and Serial” example found on Appendix A of the “Hardware Design Guide” revision HMSI-216-126 2.8 en-US.

This example (and the SPI and Serial Operation chapters) says that pin numbers #10, #33, #34 (OE,WE,CS) should be connected to 3v3 because they are not used. So I did.

That worked with the M40 Profibus-DP module with housing, but the M40 Profinet-IRT module without housing seems to have those pins internally connected to Ground, and so it was causing a short-circuit. When I disconnected those pins from the 3v3 net the problem was gone.

I only have the one module, so I can’t compare to see if it is this particular module’s problem.

Are those pins really supposed to be internally connected to ground?

#2

Hi @Santi_PH

I’ve checked with a colleague and he was saying that the device should not have those pins connected to ground. This is because they are needed for inputs for parallel

#4

Hi Tim,

Thanks again for the fast response.

That’s what I thought. So there must be something wrong with this particular module. We have already contacted the local distributor to let them know.

Thanks again for your help

#5
#6

thanks, let me know what you find out

#8

Topic closed due to inactivity.