Re: Long term analog I/O streaming (PATCH)

On Wed, Oct 09, 2002 at 05:09:35PM -0700, rhk_at_newimage.com wrote:
> 
> Message-Id: <20021010000933.D2E2EE034_at_newimage.com>
> Date: Wed,  9 Oct 2002 20:09:33 -0400 (EDT)
> From: rhk_at_newimage.com (Apache User)
> 
> I found a problem with long-term analog input and output streaming 
> when using select() or poll() to determine when to send data. 
> 
> When sampling at 1Mhz, the counters used to determine buffer space 
> wrap around every 35 minutes. At some point, buf_write_count wraps
> and becomes less than buf_read_count, so select() never indicates
> that data is available, and eventually the buffer will fill up with
> data from the card, and an overflow will occur.

Thanks for noticing this (and the other) bug.  It's simply a matter
of the difference between "a > b" and "a - b > 0".  Correctly
determining buffer fullness requires the latter.

I fixed it in CVS, could you check if it also solves your problems?



dave...

Received on 2002-10-10Z00:47:38