Subject: Re: com02: silo overslow
To: None <explorer@vorpal.com>
From: Adam Glass <glass@sun-lamp.cs.berkeley.edu>
List: current-users
Date: 01/26/1994 22:57:59
> 
> Ok, enough.  :(
> 
> What is the most recent experimental com code which works (or used to work)
> under -current?
> 
> I'd like to experiemt with anything which provides bidirectional code and
> more reliability.
> 
> --Michael
> 

Well, the first thing to do is to comment out the 
		log(LOG_WARNING, "com%d: silo overflow\n", unit);

It is doing this from inside the interrupt handler, which remarkably
dumb.  So every time you get a silo overflow, you take a long code
path detour which may result in greater lossage of sequential bits.

Don't feel guilty about it, as silo overflow should not be regarded as
a fatal error, just an indication that you aren't pulling data out of
the UART fast enough.

I believe some diffs have gone by recently to current-users (an
archive of which can be found via anonymous ftp on sun-lamp) that
fixed a few obvious bugs, and added some bi-directional tty support.

A replacement com driver may be coming down the pipe (to be
beta-tested via NetBSD-current, but there isn't a solid timeline yet.

later,
Adam Glass

ps. i think the "remove log()" thing is from Charles Hannum or Theo Deraadt

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