Re: cs8900a always returning 0x5555

On Mon, 22 May 2006 01:05:02 -0400, "Aimingoo" <aimingoo@xxxxxxxxx>
wrote:

Hi- I am working on developing cs8900a driver under linux 2.4. The system
configuration is: arm9+linux(kernel 2.4), the cs8900a is working on IO
mode and its bus address is 0x1001_0000, its default IO base is 0x300.
Problem is, cs8900a always returning 0x5555 when I read like this:

[snip]

I ' m now struggling with this problem for weeks and would really
apreciate any help on this.

But you were most likely not searching the comp.arch.embedded archives
in google cause otherwise you would have stumbled over my thread about
the exactly same problem weeks before :-) :

http://groups.google.ch/group/comp.arch.embedded/browse_frm/thread/f0f3de4465c7dc8d/80ea9027f7b0c89a?tvc=1&q=cs8900a+author%3AMarkus+author%3AZingg&hl=de#80ea9027f7b0c89a

In short, I did not had enough wait states and hence the controller
did not had enough time to set the propper value on the port.

Since I also got back 0x5555 and since your controller (arm9) is a
pretty fast one I'm somehow confident that your design suffers from
the same problem I was facing.

HTH

Markus

.

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