Re: Machine Check Exception

Hi Allan,

No, I don't think so. Nothing changed in the configuration of the RAM 
for the new hardware, and the RAM chip select is configured exactly 
the same way in the BDM setup and in the code that gets executed from 
flash. One thing that is different about the BDM configuration is 
that we're using the dual-mapping feature. Since we never have 
trouble running from BDM, though, I'm guessing that's okay. 
Everything seems to point back to the MPC555 itself. We've built 
about 25 boards so far, and the problem has only been seen on two of 
them.

Joe

--- In [email protected], "Dobbin Allan-r11834" 
<Allan.Dobbin@...> wrote:
>
> It could definately be RAM related.  Is it possible your BDM tool
> configures the external RAM correctly before it uses it, but you 
don't
> have that same setup running in the flash code before it tries to 
access
> the RAM?  
>  
> 
> 	-----Original Message-----
> 	From: [email protected] [mailto:[email protected]] 
On
> Behalf Of trailrunner23
> 	Sent: Friday, June 09, 2006 12:26 PM
> 	To: [email protected]
> 	Subject: [MPC500] Machine Check Exception
> 	
> 	
> 
> 	Hello,
> 	
> 	We've got two revisions of a custom MPC555 control board. 
We've
> had
> 	problems with machine check exceptions on the 2nd revision. We
> are
> 	using different types of RAM on the two boards, but we never
> have
> 	exceptions when running code from RAM (BDM), only when the 
code
> is
> 	running from internal flash. Can anyone shed light on whether 
or
> not
> 	this is clearly a problem of reading an instruction from
> internal
> 	flash, or could it somehow be RAM-related? Any other ideas?
> 	
> 	Thanks very much,
> 	
> 	Joe Pasquariello
> 	
> 	
> 
> 	 
> 
> 
> 
> [Non-text portions of this message have been removed]
>







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