Paul Chilton

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10 years ago.

FRDM-K64F Needs powering up twice

Has anyone else got issues with the FRDM-K64F board needing to be powered up, powered down and then powered up again before it will run.

I am seeing it quite repeatibly on multiple boards, whether powered through the USB, powered on the 5-9V input pins or powered directly on the 3.3V pins.

If you power it off and then straight back on again it is fine but after it has been unplugged for 30 seconds the next power on does not run until you remove power and put it on again.

At the moment this makes them useless for any real hardware.

Any help appreciated,

Thanks

Hi Paul,

I've seen many times where the K64F doesn't start running after being powered up. Hitting the reset switch once does get the thing up and running. Not a good situation for a remote device.

I thought about using an external power monitoring supervisor, like the TI TLV803RDBZR. However, I have not tried it yet to see if this cures the problem.

...kevin

posted by Kevin Braun 23 Oct 2014

Is this a genuine design fault or is there a reason it does this? On the board I was working with pressing the reset button didn't work, it wasn't until power was removed it kicked into life.

posted by Paul Chilton 25 Oct 2014

I think this is the NMI issue addressed in this Freescale thread https://community.freescale.com/message/443763?et=watches.email.thread

Basically - remove C55 (right near SW3). Hope that helps.

posted by Scott Swanson 18 Nov 2014

According to the link above, removing C55 does not fix the problem.

@0xc0170, has the modified "startup_MK64F12.s" (from the above link) been added to any mbed build?

...kevin

posted by Kevin Braun 05 Dec 2014
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