AM4372: About Set up receive interrupt when using UART1

user1201164

Part Number: AM4372

Hi,

We have a question from one of our clients.

They are using RTOS with AM4372 and they tried to receive 1 byte of data with the default setting of no FIFO on UART1, but the receive interrupt they were expecting did not occur and they get a receive timeout.
They have done the same thing with UART0 and it is working fine.
According to the Errata (sprz408d.pdf), I know that EDMA should not be used, but the Note does not tell me how to do it.

Best Regards,

Kouji Nishigata

over 2 years ago

0 Kallikuppa Sreenivasa over 2 years ago

TI__Guru**** 188679 points

Hello Kouji Nishigata

Thank you for the query.

Please refer the below note.

(+) Notice regarding Processor SDK TI-RTOS for AM335x, AM437x, OMAP-L13x, C674x, K2G devices - Processors forum - Processors - TI E2E support forums.

I am checking internally and will update the thread based on any inputs i have.

Regards,

Sreenivasa

0 user1201164 over 2 years ago in reply to Kallikuppa Sreenivasa

Expert 1770 points

Hi, Sreenivasa

Thanks for the reply.

I wrote that they are using an RTOS for this and it is made by 3rdParty.
Therefore, the question itself is for the bare operation of the device.
It seems that there is no 1-byte receive interrupt for UART1. Is there any kind of workaround (e.g. different settings than UART0)?

Best Regards,

Kouji Nishigata

0 Kallikuppa Sreenivasa over 2 years ago in reply to user1201164

TI__Guru**** 188679 points

Hello Kouji Nishigata

Thank you.

The TRM and the Errata would be the documents to refer.

If there is no mention of any work around, i would guess there is no workaround.

I am checking internally and will update you if i have an answer. Please expect a delay in response.

Regards,

Sreenivasa

0 user1201164 over 2 years ago in reply to Kallikuppa Sreenivasa

Expert 1770 points

Hi, Sreenivasa

Is there any progress on this matter?

Also, this question is becoming a confirmation of Errata, but the customer's question is that the receive interrupt does not occur.
Has TI confirmed this phenomenon? When I look into past questions, I see many examples of UART1 not transmitting when using FIFOs. However, I could not find anything about receiving.

Best Regards,

Kouji Nishigata

0 Kallikuppa Sreenivasa over 2 years ago in reply to user1201164

TI__Guru**** 188679 points

Hello Kouji Nishigata

Thank you for the additional inputs.

I am checking internally and will update you when i have an answer from the experts.

Regards,

Sreenivasa

0 user1201164 over 2 years ago in reply to Kallikuppa Sreenivasa

Expert 1770 points

Hi, Sreenivasa

Is there any progress on this matter?

I would like to inform my customer if there are any cases of UART1 receive interruptions.

Best Regards,

Kouji Nishigata

+1 Kallikuppa Sreenivasa over 2 years ago in reply to user1201164

TI__Guru**** 188679 points

Hello Kouji Nishigata

Thank you for checking.

Please refer below inputs i received from the expert and also thread that seem to mention UART1 works

I do not see any reason why this should not work. The UART1 interrupts go to the same targets as UART0.

https://e2e.ti.com/support/processors-group/processors/f/processors-forum/581479/starterware-am4376-bare-metal-example-on-uart1

https://e2e.ti.com/support/processors-group/processors/f/processors-forum/782826/linux-am4372-customboard-rs232-on-uart1

https://www.ti.com/lit/an/sprac32a/sprac32a.pdf

https://e2e.ti.com/support/processors-group/processors/f/processors-forum/997992/how-to-configure-and-use-uart1?tisearch=e2e-sitesearch&keymatch=AM437%25252525252520UART1%25252525252520interrupt

Here are some debug steps expert proposed

I suppose there could be an a interrupt enable (other than in the UART register set) that needs to be set in order for the UART1 interrupt to reach the processor.

A quick search found this: https://e2e.ti.com/support/processors-group/processors/f/processors-forum/997992/how-to-configure-and-use-uart1?tisearch=e2e-sitesearch&keymatch=AM437%25252525252520UART1%25252525252520interrupt#

However, looks like the customer has already found other UART1 threads, perhaps including this too.

Have they probed the signal to be user the UART input has activity?

Have they checked the pinmux registers are configure correctly?

It may be an idea to dump the UART1 related registers to ensure they have been correctly configured.

Regards,

Sreenivasa

0 user1201164 over 2 years ago in reply to Kallikuppa Sreenivasa

Expert 1770 points

Hi, Sreenivasa

Thanks for your answer.

The customer will look into this with reference to the information in the document.
If they are unable to resolve the issue, we will open a new question, so please let us close this one for now.

Best Regards,

Kouji Nishigata

0 Kallikuppa Sreenivasa over 2 years ago in reply to user1201164

TI__Guru**** 188679 points

Hello Kouji Nishigata,

Thank you for the note and understand.

Regards,

Sreenivasa