Michael H.

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7 years, 10 months ago.

How to program custom board with mbed bootloader

Hello, i use usbdm v2.1 and I need to program my custom board. The board is cleanly soldered and 3x checked.

I get the error message that it cannot reset/halt the device. Checking the reset pin, shows that the reset pin is oscillating.

How do I program my custom board now with mbed (MCU is the same)

-Michael

1 Answer

Andy A
7 years, 10 months ago.

"How do I program my custom board"

Well the first thing to do is figure out why the reset pin is oscillating because it shouldn't do that.

Can you post schematics, a photo and the board layout files? (Gerbers or images of the layers if possible, if not a photo where you can see the tracks clearly)

Accoring to freescale it's normal the the reset pin oscillates. https://community.nxp.com/thread/337145 Their explanation is, that this is fixed after programming.

Regarding the connections, I connected. -SWD_CLK_TGTMCU -RST_TGTMCU_b -SWD_DIO_TGTMCU -(GND and Vcc)

Reset has an pull up, everything is straitly connected.

(I'd love to post some images, but I cannot see the possibility to attach images here)

posted by Michael H. 11 Jul 2016

One more commend: The MSB Bootloader puts out the following message: The interface firmware FAILED to reset/halt the target MCU

posted by Michael H. 11 Jul 2016

Odd. If the reset is supposed to do that it would imply either a problem with the programmer connections or less likely possibly a power supply/decoupling issue causing the system to fall over as soon as it tries to talk. Can you scope the other connections and see that they are toggling?

I'm not sure how you can upload images but you can link to them by using

{{/static/img/mbed.gif}} a local limage on the mbed site
{{http://somewhere.com/static/img/mbed.gif}} an image somewhere else

You can also post links by using [[http://link.com/file]] or 
[[http://link.com/file|Optional text description]]
posted by Andy A 11 Jul 2016

What wires do i connect and to verify for a proper programmer connection? Above I mentioned 5 wires -SWD_CLK_TGTMCU -RST_TGTMCU_b -SWD_DIO_TGTMCU -(GND and Vcc) - Are they correct? Or is there the error? (Power problems we can exclude here for sure...)

posted by Michael H. 11 Jul 2016