Answers to UNIX PC Commonly Asked Questions

[Robert J. Granvin]

>>11. Some AT&T serial boards do not work right.  How are they identified?
>>The EIA boards (or EIA/RAM) in question are anything RELEASE F or higher.
 
>Does anyone know what symptoms are displayed by these boards that "do not work
>right?"  I've been having some terrible problems with flow control on one
>of my ports and have just about given up getting my NEC LC-890 to work with
>it.  It never works at 9600 baud, and only works sometimes at 4800 baud.
>The symptoms are buffer overflow on the NEC, the 3B1 just keeps on sending,
>but SOMETIMES it works!  Really tough to debug.  (3.51 kernel, STARLAN card,
>EIA/Combo card).

The major problem with these boards is that the board is unwilling to
send a BREAK to the device attached.  It can also crash your system at
unexpected (and sometimes expected) times.  The system could simply
hang, or it could panic.  If the system doesn't crash, the remote
device itself might simply get "hung".

Hardware Flow Control is broken on all versions of OS 3.51.  Fixdisk
2.0 (aka 3.51c) will repair HFC.  If you are having problems with HFC,
it's HFC's fault, not your equipment.  And, to sound like a broken
record, "Fixdisk 2.0 will be available sometime in the near future."
Sigh.

-- 
"A cowboy should know his horse, but it                      Robert J. Granvin
 seemed to the podners at the Triple Q            National Information Systems
 Ranch that Vernon McChew had gotten                         rjg at sialis.mn.org
 TOO close."                                ...{amdahl,hpda}!bungia!sialis!rjg