topic HCS08 QE4 can't connect with OpenSource BDM in 8-bit Microcontrollers

HCS08 QE4 can't connect with OpenSource BDM

gaminn — Fri, 30 Oct 2009 14:34:57 GMT

Hello,

I use HCS08 QE4 MCU along with OpenSource BDM. Suddenly I can't connect to MCU (I'm not aware that I did something wrong with my board where the MCU is at the time the problem appeared).

The program that is loaded in MCU is running correctly

I caught some waveforms. When I connect MCU to OpenSource BDM the waveforms are deformed:

http://gaminn.sweb.cz/MCU/bad.gif

http://gaminn.sweb.cz/MCU/bad2.gif

(voltage between GND and 3.3V appears on the line, edges of signal are not steep)

When I disconnect MCU the output signal of OpenSource seems not to be deformed.

Is there anything you can advise to me?

Thank you

Martin

Re: HCS08 QE4 can't connect with OpenSource BDM

gaminn — Fri, 30 Oct 2009 15:52:32 GMT

It's me again I replaced the MCU with another one. I have no problems to connect to it. I loaded my project to it ( http://gaminn.sweb.cz/MCU/project%20-%20erasing%20flash.zip ). It should erase 0xF800 page of the MCU flash. When I ran the program, the MCU became uncontrollable in debugger. Now I'm not able to connect to it again...

Message Edited by gaminn on 2009-10-30 08:55 AM

Re: HCS08 QE4 can't connect with OpenSource BDM

pgo — Tue, 03 Nov 2009 07:35:09 GMT

Dear Gamin,

I'm not sure what the problem is but sometimes the BDM can have trouble connecting if the device is not programmed correctly.

You can try the technique here

SG8 continuous reset

You should also try unsecuring the device.

bye