RAK 7391 - UART of the PI Header

LPWAN Industrial Gateways / Concentrators WisGate Connect RAK7391
#1

Hi there,
due to no answer regarding my question via mail I am posting here again.
We do use the RAK Connect with a PI, multiple MPCIE cards (Lora, LTE, GPS) and a PI Hat with UART connected to the standard PI GPIO.

The UART on the PI Hat on pins 8 and 10 should be (in my understanding) connected to the PI CM4 UART0 and when accessed via Minicom/Screen/Whatever i should get the data of the PI HAT connected to, right?

When I do connect to ttyS0 there are multiple GPS messages of the LORA connected to MPCIE1 and even of the connected LTE on MPCIE2.
How is this even possible ? Stating this image, the UART should only be routed to the GPIO. Is there any software relay in your software?

grafik
grafik1104Ă—791 172 KB

Please let me know what the actual routing of the ttyS0 is or how to access ther GPIO Uarts on Pins 8 and 10.
Thank you.

#2

Hi,
due to no repsonse here yet I am just reposting.
My original ticket was mailed at 06.06 to the support.
@xoseperez or @velev can you help ?

#3

Hi @AdrianDE
Sorry you message was not answered before.
UART0 on the CM4 is connected to both the 40-pin header the mPCIe stot #1 pins 31 and 33. There is currently no way to unroute this. I would suggest moving the LoRa concentrator from Slot #1 to slot #2.

#4

Hi @xoseperez thank you very much for your answer.
This is a crucial information and should be added to the Documentation asap.
The UART as is here is not a Bus and therefore it cant be used by the hat when added the LORA5146 to the MPCIE1 or any other MPCIE which has UART on the pins 31 and 33. Furthermore this is not standard and makes this rpi hat for the stated “Compatible” devices unusable! For example the give ALFA Network is marked as compatible but it just works when there is not other uart connected or said different : No device which sends on pins 31 and 33 on the MPCIE is connected!
I dont now how to deal with this now but i will have a look…

#5

The assembly guy has been updated on the docs center and our assembly team is aware of this now.

We have added thew issue with the UART lines to the backlog for the next hardware release.

Thank you!

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