On Fri, 5 Jan 1996 20:12:54 -0500 
 David Gilbert <dgilbert@pci.on.ca> wrote:

 > 	It only happens with completely flooded serial activity.  I
 > don't believe that you would experience this with the mouse or
 > keyboard.  It happens at the times when necscape or ncftp say they're
 > getting 1.2-1.6 K/s over the connection.  Remember that the ppp
 > connection is the primary network connection for thise beast.  I have
 > seen it happen during sup transfers, too.

Hmm ... Like Paul, I suspect some sort of race condition between the zs 
and clock interrupt handlers ... Maybe this weekend I'll have some time 
to help you debug it...

 > 	This is set in sparc/dev/zsvar.h ... and used in zs.c

Really?

zsvar.h:#define ZRING_RINT      1               /* receive data interrupt */
zsvar.h:#define ZRING_XINT      2               /* transmit done 
interrupt */
zsvar.h:#define ZRING_SINT      3               /* status change 
interrupt */
zsvar.h:#define ZRING_TYPE(x)   ((x) & 3)
zsvar.h:#define ZRING_VALUE(x)  ((x) >> 8)
zsvar.h:#define ZRING_MAKE(t, v)        ((t) | (v) << 8)

What line?

--------------------------------------------------------------------------
Jason R. Thorpe                                       thorpej@nas.nasa.gov
NASA Ames Research Center                               Home: 408.866.1912
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