It suddenly happened that my DM642 board failed to run to the main(). While
debugging, I found that c_int00 can't pass some assembly codes, which is to
wait for the reset complete of VP1. I checked the register VP1_CTL, and
found that VPRST field is 1, which means it can't finish the power on
reset. but both VP0 and VP2 are OK, seeing their control registers. Does
anyone know why?
Reply by Randy Yates●December 7, 20052005-12-07
Well you could obviously have a bad part. There also might
be a conflict with the reset logic if you had some external
drive on the video port control signals. I'd check those
signals and see if something's driving them. Otherwise
I'd say your part is dead.
Reply by Mark Robinson●December 8, 20052005-12-08
Randy Yates wrote:
> be a conflict with the reset logic if you had some external
> drive on the video port control signals. I'd check those
> signals and see if something's driving them.
I had that problem when trying to use a Conexant decoder with the
video port. Essentially, the video port wouldn't come out of reset
until I'd properly programmed the decoder. It seems Philips and TI
decoders come out of reset into some sensible default state, but
Conexant decoders enter a standby state with outputs tri-stated.
If a previously working system has failed, then it could be a
dodgy decoder, or maybe the decoder has got itself into a funny mode?
hmq - you say that the program gets past the C entry point, but
doesn't reach main(). I'm guessing that it stopping in the
mdBindDev for your video port driver, in which case you will probably
have source code for it, which might make debugging easier.
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so that answers your next question..."
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