topic MCF52258 Not running without debugger attached in ColdFire/68K Microcontrollers and Processors

MCF52258 Not running without debugger attached

RxScram — Sat, 01 May 2010 03:12:41 GMT

Hi Everybody,

I've searched through the forums and found similar problems, but I didn't think any of the other problems were relevant.

My problem is this: I have programmed the flash in my 52258, and if I run it with the BDM attached, it works fine. However, if I try running it without the BDM, it does not run. The interesting thing is that I do not do anything with the BDM... I just have it plugged in, without even having codewarrior running, and then I turn on the power and it runs fine. If I turn off the power, unplug the BDM, and turn the power back on then nothing happens.

I think this could be a hardware design problem on my part, but I am not sure what it could be. Any suggestions? My BDM pinout is as suggested by the MCF52259RM document, and is basically identical to the eval board. Since the BDM works great, I don't think that the error is in that portion.

Thank you.

Re: MCF52258 Not running without debugger attached

scifi — Sat, 01 May 2010 05:35:53 GMT

This problem should be easy to solve.

Assuming signals from the debugger are static, attach the debugger and write down the voltage levels it supplies to the MCU. Then detach it and do the same. You should now see what changed.

I have a MCF52259-based design running. No surprises, works like a charm.

Re: MCF52258 Not running without debugger attached

RxScram — Tue, 04 May 2010 00:35:10 GMT

Thanks, I should have done that on my own first. I needed to add a pull-up on /bkpt, it was as simple as that.

Re: MCF52258 Not running without debugger attached

trusc — Fri, 27 Jan 2012 18:25:07 GMT

I had the same problem on a board using the MCF52255. Problem solved after reading your posts.

Thanks - I'm pretty pleased about having found a solution to this problem! :smileyhappy: