[U-Boot-Users] 405Gpr timer interrup

Wolfgang Denk wd at denx.de
Thu Apr 10 23:28:02 CEST 2003

In message <EGEGIJHKDKJGAJMGIDPNOEJPCKAA.jwalden at digitalatlantic.com> you wrote:
> >Does the "sleep" command work, with correct timing,
> >i. e. will "sleep 5" sleep for approx. 5 seconds?
> Yes - however that is using udelay which does not seem
> connected to the timestamp which is incremented in the PIT
> handler.

Right. But it gives an indication  if  your  clock  configuration  is
approximately oK. I was just eliminating potential problems ;-)

> Anyway... I figured one reason why the PIT was not causing
> the timestamp to interate - I had interrupts turned off.
> I had interrupts_enable commented out from my very first days
> of working on u-boot.


> Now - when I turn the interrupts on and then - and only when -
> I enable the PIT - u-boot gets a ProgramCheck.
> So - Just to check, I looked to see if there was an address for
> a handler in the Interrupt Vector Table for the PIT - and I did
> not find a valid address.
> However to cross-check myself, I looked in the IVT for the ProgramCheck
> vector (I used the BDI to dump 0x700) there was not a valid address there
> and no code.
> So the question now is what should the IVT look like, and at what addresses
> should there be either vectors or code?

Where did you check? In flash, before relocation, or  in  RAM,  after

Wolfgang Denk

Software Engineering:  Embedded and Realtime Systems,  Embedded Linux
Phone: (+49)-8142-4596-87  Fax: (+49)-8142-4596-88  Email: wd at denx.de
Proboscis: The rudimentary organ of an elephant which serves  him  in
place of the knife-and-fork that Evolution has as yet denied him. For
purposes of humor it is popularly called a trunk.    - Ambrose Bierce

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