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Re: Serial overruns


Matt Holgate wrote:
> 
> Jonathan Larmour <jlarmour@redhat.com> writes:
> 
> > Still, hardware flow control should prevent this. It looks like it's gotten
> > broken since the PC target uses the generic 16550 serial driver (assuming
> > you are using anonymous CVS, not 1.3.1), and that supports it.
> 
> What, even though it is the FIFO in the chip that is overflowing? I
> thought the hardware flow control was activated by software when the
> buffer in the serial driver reached the high watermark? If this is the
> case, then hardware flow control won't help a bit...or can the UART
> itself active flow control?

I also meant that the processor would have to be really slow (or
interrupts/DSRs disabled for a long time) for it to miss the opportunity to
run the DSR. If you are (as I recall) on a PC, then assuming it is recent
it should have more than enough oomph.

You could try looking at lowering the RX threshold, but it's looking like
there's something else going on.

A thought: do you have the network package in your configuration? If so,
try removing it ("ecosconfig remove net").

> I'm using anonymous CVS, although not the very most recent version so
> I'll do an update first.

I don't believe anything has changed in this area for a while.

Jifl
-- 
Red Hat, Rustat House, Clifton Road, Cambridge, UK. Tel: +44 (1223) 271062
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