Jiffy Boogle

Important changes to forums and questions

All forums and questions are now archived. To start a new conversation or read the latest updates go to forums.mbed.com.

8 years, 12 months ago.

Recover

I have been flashing my K64F until it appears to have bricked.

When I try to flash a new program, it returns a fail file which says it failed to gain control of the MCU interface.

The green LED and red reset LED are solid.

Any ideas on how to fix this?

Thanks

Question relating to:

Last updated: 27 Aug 2020
The Freedom-K64F is an ultra-low-cost development platform for Kinetis K64, K63, and K24 MCUs.

2 Answers

Martin Kojtal
8 years, 12 months ago.

What I do sometimes - reflect the interface firmware (go to bootloader mode, upload new interface chip). I would use pyOCD, there's a test script which tries to unlock the chip, that could help. Or sometimes I just use jlink (jlink interface is also available for openSDA), which provides unlock command.

Thanks, I am hoping jlink is my last resort as I do not currently own the hardware to do that.

Never heard of pyOCD so will give that a try.

Thanks

posted by Jiffy Boogle 25 Nov 2015
Erik -
8 years, 12 months ago.

Did you flash a specific program which might have bricked it? Such as for example turning the reset pin into GPIO? I have unbricked a number of chips by using the free version of Keil, making sure it used the CMSIS-DAP debugger (which the K64F has with mbed firmware), and then running mass erase. This generally resulted in errors, and then I tried different debugger settings (it can for example put it in reset in a few different methods, in the example of turning the reset pin into GPIO changing that was a way to unbrick it). In the end I managed to unbrick different devices everytime, however this is based on having programmed it with code I shouldn't have used. If you have regular code where this is not the case, just erasing flash might not help alot.

+1 for keil, forgot to mentioned that. I used it as well. Sometimes even reset holding, release and quickly press mass erase :-) otherwise an interface chip could not reset the target

posted by Martin Kojtal 25 Nov 2015

Try this method unfortunately when it comes to try the erase Uvision returns an error of "SWD/JTAG Communication Failure". I feel the board may be unrecoverable.

posted by Jiffy Boogle 26 Nov 2015