Zephyr UART Asynchronous API continuous data receiving

RE: Zephyr UART Asynchronous API continuous data receiving

Pedro — Mon, 06 Feb 2023 11:07:32 GMT

Hi,

I removed all LOG_ and malloc functions. Take also a look to this post. It may help you.

Regards,

Pedro.

RE: Zephyr UART Asynchronous API continuous data receiving

mahq — Fri, 03 Feb 2023 15:18:04 GMT

Hello, thanks for sharing your solution, I'm having the same issue. When receiving data that are larger than my UART buffer size i.e. when allocating more than one buffer i always seem to loose three bytes in the transition between those two buffers.

What kind of things did you remove in the interrupt handler in order to get it to work?

Kind regards,

RE: Zephyr UART Asynchronous API continuous data receiving

Pedro — Tue, 28 Jun 2022 14:19:32 GMT

Hi all,

I've finally solved it. The problem was doing too many thins inside the interrupt handler of UART. When I reduce to minimum the things done in the interrupt handler, all work as expected.

I hope this can help somebody.

Regards,

RE: Zephyr UART Asynchronous API continuous data receiving

Pedro — Sat, 25 Jun 2022 22:23:42 GMT

Hello Kazi,

Do you mean disabling and re-enabling UART?

I tried disabling and re-enabling UART each time I receive something and some bytes are also lost.

Thanks you.

RE: Zephyr UART Asynchronous API continuous data receiving

Kazi Afroza Sultana — Fri, 24 Jun 2022 22:20:32 GMT

Hello Pedro,

Have you tried to restart the UART to workaround this?

Thanks.

Best Regards,

Kazi Afroza Sultana

RE: Zephyr UART Asynchronous API continuous data receiving

Pedro — Fri, 24 Jun 2022 07:24:35 GMT

I can answer to myself the last issue, about not working when defining 256 o 512 bytes buffers. RXD.MAXCNT register in UARTE0 (Maximum number of bytes in receive buffer) is 8 bits. When you write 256 o 512 to it, you are actually writing a 0 to that 8 bits.

Surprisingly this is not detected as an error by uart_rx_enable(). Could it be possible to fix this for future releases?

About the other problem, I've simplified a lot my code, but I'm still receiving less bytes.

If the buffer is 40 bytes, and I send 90 bytes length string

#abcdef-10,ghijkl-20,mnopqr-30,stuvwx-40,abcdef-50,ghijkl-60,mnopqr-70,stuvwx-80,abcdef-90

I receive 3 UART_RX_RDY events:
1^st with #abcdef-10,ghijkl-20,mnopqr-30,stuvwx-40
2^nd with ,abcdef-50,ghijkl-60,mnopqr-70,stuvwx-80
3^rd with ,a (Missing 8 bytes)

Then, if I continue sending chars, I start receiving the 'lost' chars, for example:
I send 123, I receive bcd, then I send 4 and receive e and so on, until I fill the 40 bytes buffer and I receive all the 'delayed' data.

What I'm doing wrong??

Thanks again!