Teensy 3.6 on own PCB

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Paula

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Hi,

I'm working on a project that I wish to use the teensy 3.6 for, but as the board space is a bit tight, I'm rolling my own PCB.
I've made the PCB (4 layers) and used the QFP MK66FX1M0 rather than the BGA, I've got the QFN MKL02 bootloaders from PJRC and pretty much copied the Teensy 3.6 schematic (https://www.pjrc.com/teensy/schematic.html) though I've missed out a few parts that I don't need.
The board is running of it's own 5V supply, so no need for USB power. I have added a reset chip (STM1868) as previous experience has shown me that without one things don't always start as expected.

Here's the schematic;

Teensy_QFP_Schematic.jpg

And here's the board layout (i'm aware this doesn't show the link from pin 21 (VREGOUT) to the 3.3V, I added a link following reading the troubleshooting guide here - https://www.pjrc.com/store/ic_mkl02.html);

Teensy_Board_Layout.PNG

The Board is a 4 layer 1.6mm PCB, and I've kep all signals well away from the cyrstal.
The Main Crystal is a 16Mhz 6pF (Q24FA20H0005912), so I don't think that's the problem.
I have assumed (and this could be where I'm going wrong) that the bootloaders when purchased in chip form include the "blink" program (hence my LED).

I'd appreciate any advice, many thanks in advance.

Paula
 
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So, just for a giggle, I connected the USB to my PC and got "Kentis Bootloader ready for use".
So, I assume that for some reason the device isn't booting from the MKL02.

Or is there another step I need to do?
 
ok, so, I tried (for the hell of it), uploading blink to my board and... bingo, LED blinking..
So I guess, the bootloaders don't come with blink on :)
 
The blink program runs always from the main CPU, not from the MKL. The latter handles mostly only the uploading from USB to the main CPU and the reboot process. Teensys bought from PJRC come with pre-flashed blink. If you use a non PJRC main CPU, it will naturally not be pre-flashed with blink, even when using the MKL from PJRC.
 
Thanks, I assumed the code was held in the MKL02 rather than the MK66, my bad.
But still she's alive :)
 
One final question, the MKL chip isn't needed once the main CPU is flashed?
Is that correct?
 
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