FRDM-K22F, UART Rx (callback) Makes MQX Weird

[jeffreygraves]

If I send enough characters to the UART, I can make MQX act weird*.

*MQX will stop running a task or...

*MQX will stop running more than one task or...

*MQX will run a task open loop, ignoring wait functions (ie OSA_TimeDelay()).

I have attached a "bare bones" project that reproduces this behavior.

This project uses a UART Rx data callback function.

(This simple project does not do anything with the received chars.)

This project targets the FRDM-K22F development board.

This project uses the following software:

KDS 2.0

KSDK 1.1.0

MQX-KSDK

PEx

The project configuration is straight forward and what you get with PEx.

I have not taken any steps to install other interrupt handlers.

Steps to reproduce:

Comm settings: 115Kbps,N,8,1

Monitor the referenced I/O pins...

Repeatedly paste a string (~80 char) into a terminal app like Tera Term.

Eventually, the toggling I/O (square wave) will change indicating a MQX problem.

I have reproduced this problem with and without a Tera Term character delay (1ms).

Has anyone else seen this problem?

This issue is affecting the stability of a more complicated product.

Any feedback would be greatly appreciated.

Thanks,

Original Attachment has been moved to: UART_Rx_Makes_MQX_Wierd01.zip

[mjbcswitzerland]

Hi Jeffrey

You may have more success posting in the MQX and/or PE forums since this sounds like a software issue rather than a Kinetis/K22/UART problem.

MQX Software Solutions

https://community.freescale.com/community/pex

Regards

Mark

Kinetis: µTasker Kinetis support

K22: µTasker Kinetis FRDM-K22F support / µTasker Kinetis TWR-K22F120M support

For the complete "out-of-the-box" Kinetis experience and faster time to market

[jeffreygraves · Accepted solution]

Mark,

I did also post it to "MQX Software Solutions".

https://community.freescale.com/thread/352874

I will note here if I get an answer there.

Thank you,

**Solved**

See post in "MQX Software Solutions".