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RE: CS8900: Tx interrupt lost


i had this problem and i believe it was caused by transmit underruns
(which come in the form of a buffer event).  having the transmit
underrun event handler release the buffer instead of the other code
eliminated having to wait for a timeout.  you can also change the
transmit command to wait until more bytes have been written to the
controller before starting packet transmission.

> -----Original Message-----
> From: Peter Graf [mailto:p.graf@itknet.de]
> Sent: Tuesday, August 14, 2001 4:50 AM
> To: ecos-discuss@sourceware.cygnus.com
> Subject: Re: [ECOS] CS8900: Tx interrupt lost
> 
> 
> Trenton D. Adams wrote:
> 
> >What does that mean exactly?  Maybe 250ms isn't long enough for a
> >transmit?
> >
> >CS8900: Tx interrupt lost
> 
> Don't know about your target. Mine is a custom Hitachi SH3.
> 
> I had the same problem, if I just rely in Interrupts for Transmission.
> On my target, the problem would not disappear if I send 
> shorter packets or
> use a longer timeout.
> 
> It seems that the interupts are really lost, either due to a 
> hardware problem
> of the Cirrus logic chip, or unlucky programming of its registers.
> 
> I worked around the problem by polling the device in addition 
> to using the
> interrupt.
> 
> Peter
> 
> 


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