topic Re: Serial Debug link not working in MCUXpresso General

Serial Debug link not working

rstone — Fri, 05 Jun 2020 21:29:04 GMT

MCUXpresso IDE, TWRK81F150M board.

I'm new to this IDE and board, and though I've set it up according to the quick start, the IDE can't connect to it for debug or console access.

When it is initialized, there's a sample demo app that runs, so I know the serial->usb link is working, but I can't seem to get the demo to quit so I can download, run and debug any new code. I've tried resetting the board for a firmware update, ctrl-c and sending breaks. If there's a jumper that needs to be moved, it's not documented (or not apparent) and though I've read all the startup documentation I can find, they just presume the serial debug link works and that the debugger can talk to the board over the serial link, but I show "device not present".

Anyone familiar with board above or its like who can assist me in getting past the demo?

Re: Serial Debug link not working

jingpan — Mon, 08 Jun 2020 08:15:20 GMT

Hi Richard,

What application do you use in openSDA, CMSIS-DAP or Jlink or P&E?

When you connect usb, is there a new driver appear in windows?

Regards,

Jing

Re: Serial Debug link not working

converse — Mon, 08 Jun 2020 13:12:49 GMT

How are you connecting the debugger to your board? It sounds like you are using UART (COM port) - you should be using USB.

Re: Serial Debug link not working

rstone — Mon, 08 Jun 2020 15:03:35 GMT

Thank you both for replying. The only connection between the host and board is the USB connector - which provides a serial port on both Unix and Windows hosts I've tried. The sample app (a secure pin entry demo) starts when I open the serial port, and I can see its output in putty or minicom, responsive to keypresses on the board's PIN pad..

I've been trying to use what I presume is the JLink connection to the IDE on the host, but it cannot establish a connection when I specify the comm port created by the USB connection. I have tried it both with the putty/minicom instance still running and after shutting down putty/minicom.

Thanks,

Rich

Re: Serial Debug link not working

converse — Mon, 08 Jun 2020 16:42:24 GMT

I'm not familiar with your board, but on many of the tower boards, there are 2 USB connectors - one connected to the MCU and the other is used for debugging (OpenSDA). Check you are using the correct one - check the board documentation for details

Re: Serial Debug link not working

rstone — Mon, 08 Jun 2020 16:52:17 GMT

This board only has a single USB micro connector for serial and power. I'm beginning to suspect I'll need a JTAG connector to talk to the board, then.

Thanks,

Rich

Re: Serial Debug link not working

converse — Mon, 08 Jun 2020 17:11:37 GMT

I can’t find the board you are referring to. The only one I can find is this

TWR-K80F150M|Tower® System Board|Kinetis® MCUs | NXP

some number except 80 instead of 81.

can you send link to the board that you are using?

Re: Serial Debug link not working

rstone — Mon, 08 Jun 2020 18:09:44 GMT

Looking at the picture of the board you referenced, it is similar, but only contains the one power/serial micro USB connector - and it's definitely a serial port since it configures a port on the host when attached, and outputs to it.

The doc you referenced shows it is general to K80, K81 and K82 processors, and all are Cortex-M4 32-bit 4-core processors, but the K81 board has crypto hardware and tamper detection hardware.

Unfortunately, everything relating to the K81F150M that I have, appears to be released to us under NDA, so I can't provide a link to my specific SDK. :,(

Here is a link to the public NXP K81 information page for the board I'm using. I can access it after logging out from NXP, so it should be public information:

https://www.nxp.com/design/development-boards/tower-development-boards/mcu-and-processor-modules/kinetis-modules/kinetis…

Thank you so much for your attention so far, and I'm hopeful maybe you'll be able to offer some insight I'm lacking.

Regards,

Rich

Re: Serial Debug link not working

converse — Mon, 08 Jun 2020 19:24:15 GMT

Ok, it’s the POS board. You need a debug probe as there is no onboard debug. Get LPC-Link2 (OM13054). It costs about $25.

note that there is no such thing as ‘serial debug’ with Cortex-M, it is all SWD based, which means you need a debug probe.

Re: Serial Debug link not working

rstone — Thu, 25 Jun 2020 23:11:19 GMT

The LPC-Link2 boards proved very difficult to get in, thanks to COVID I guess, as in we ordered them over 2 weeks ago but they still haven't arrived. Ended up getting a Segger J-Link unit off Amazon, and one of our techs was able to fabricate a cable to match the respective connector pinouts, and that seems to work fine.