topic Re: MKE02Z64VQH4 UART Buffer Overrun Problem in Kinetis Microcontrollers

MKE02Z64VQH4 UART Buffer Overrun Problem

advangorp — Fri, 30 Nov 2018 12:39:31 GMT

Hello I am developping software for the above mentioned processor.

I use Processor Expert with the Serial_LDD component.

I am lost with the following problem.

Upon receive sometimes the AS1_OnError fires. If I then examine the error I get the

AsyncErrorCodes.errName.OverRun error. But there are no characters in the buffer (AS1_GetCharsInRxBuf() will yield 0).

I tried several buffer sizes but the spurious errors persist.

I examined the serial data quality with an oscilloscope and found it to be clean;

Can someone please advise?

Thanks, kind regards Ad

Re: MKE02Z64VQH4 UART Buffer Overrun Problem

jingpan — Tue, 04 Dec 2018 08:13:13 GMT

Hi,

Sometimes baudrate mismatch will cause receiving a break character. One of its effect is set the overrun flag, S1[OR].

https://community.nxp.com/message/1054788

Does it receive error data or the data received less than send data?

Regards,

Jing

Re: MKE02Z64VQH4 UART Buffer Overrun Problem

advangorp — Tue, 04 Dec 2018 10:14:02 GMT

Hello Jing thank you very much for your reply,

Yes I receive a buffer overrun while there are no characters in the buffer. I am sure the baud rate is ok..

I will follow the link you provided to see what could cause this phenomena.

Kind regards, Ad

Re: MKE02Z64VQH4 UART Buffer Overrun Problem

advangorp — Sun, 16 Jun 2019 15:54:03 GMT

Forgot to update this question. I found the classic error that the time spend in the receive interrupt was very much too long. The solution was to set a flag in the receive interrupt and handle the major of the code in the main loop.

Thank you for your support. Kind regards Ad