Run OFW heat spreader test

Richard A. Smith richard at
Mon Jan 23 00:02:42 EST 2012

On 01/22/2012 09:00 PM, Sridhar Dhanapalan wrote:

 > We are using a custom olpc.fth to present a boot menu so that users
 > can easily flash their XOs. As a precaution, we run a lid switches
 > test before the OS installation begins. Some of our XOs have older,
 > less effective heat spreaders, and we would like to catch these before
 > they get burnt-out by the flashing process.

The CPU has an internal thermal shutdown.  It won't burn out.  I run 
1.5's without heat spreaders all the time.  The reason you want to catch 
them is that fs-update will hang.

 > The automatic lid switches test is confusing some teachers. Ideally we
 > only want to run the heat spreader test part of it, so that the test
 > is transparent and the user doesn't need to close the lid.
 > Is this possible?

Yes.  I don' have a 1.5 with me at the moment but from looking at the 
OFW source I think you want ' .temp-rise '.

ok .temp-rise

That should run the thermal test and print a pass fail message.  It also 
returns back a true or false on the stack for if the test passes or fails.

Richard A. Smith  <richard at>
One Laptop per Child

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