9S12DP512 - flash memory damage

[prog_ram]

Hello,

I was testing and working on my board with (HCS12 DP512 MCU) and an accidental shortcut happened.

The board's parts seem to work without any problem. However, the program stopped at a certain point.

I run the Debug tools to see what's the problem, and it turns out that all the code in the first Fixed page are not executed.

Trying to flash the MCU again, it stops flashing and gives me error message that an address in the first fixed page couldn't be flashed.

questions are:

if a shortcut happens and the MCU is damaged, how could it still communicate with the debugging tools and execute part of the code? (is that possible?)

is it possible that a part of the flash memory is damaged?

and how do I verify that?

thank you and appreciate any help. 

regards,

 --
Alban Edit: FSL Part Number must figure in Message Subject line.

Message Edited by Alban on 2007-07-17 02:11 PM

[JimDon]

prog_ram,

First I assume you mean a short circuit.
What pin did you short out?

Hard to believe that a short on an external pin killed flash, so let me ask you, how are you attempting to reflash?

That is what tool are you using to flash with?

Are you erasing first?

Is there any protection set on the chip?

If so, you may have to do a bulk erase and reflash everything.

[prog_ram]

Hello,

Thanks for the reply,

I am not sure which pin was short out.

I was connecting some wires and all of the sudden the program stopped!

I didn't get any reset on the MCU, the program just stopped.

after trying to re-flash everything, and I always erase before flashing, the flash memory couldn't be flashed.

I followed Alban's advice and I connected COSMIC for their advice and I followed all their instructions, and the results were , well, nothing!

I had to replace the MCU!

I am in a process to put another one, hope there won't be any problem.

it's worth mentioning that this MCU was flashed and re-flashed several ten times, and I got no problems at all.

thank you for the help..

I will keep you updated if something comes out..

[Alban]

Hello,

Here are a few answers. Next time remember to put the device name in the subject line, as it wastes my time editing messages.

if a shortcut happens and the MCU is damaged, how could it still communicate with the debugging tools and execute part of the code? (is that possible?)

-> Yes, it is possible. You don't need the flash to run the debugger, you just need the CPU, RAM, CRG, OSC and DBG+BDM modules to work.

 
is it possible that a part of the flash memory is damaged?

-> Yes, but may be you can recover it.

and how do I verify that?

-> You can do programming/verify to check that the content of the flash matches your code.
You can force 2 erases before doing 1 programming to TRY and get the cell back to normal.

It all depends on how/when the programming crash occured.
The best for reliability would be to use another MCU.

Regards,
Alban.