4.1cBSD/usr/man/man4/vv.4v

.TH VV 4V 3/26/82
.UC 4
.SH NAME
vv \- Proteon proNET 10 Megabit ring
.SH SYNOPSIS
.B "device vv0 at uba0 csr 161000 flags 0x8003 vector vvrint vvxint"
.SH DESCRIPTION
The
.I vv
interface provides access to a 10 Mb/s Proteon proNET ring network.
The flags value is used to define the 
network to which the interface is attached.
The host's address
is discovered at boot time by putting the interface in
digital loopback mode (not joining the ring)
and sending a broadcast packet from which the source
address is extracted.
The current ring/Internet address mapping simply uses the 1-byte
ring address as the least-significant byte of the Internet address.
If, for example, the host number is 24 and the network number
is 128.3.0.0 (as in the configuration line example above),
the Internet address of the interface would be 128.3.0.24.
.PP
The interface software implements error-rate limiting on
the input side.
This provides a defense against situations where other hosts
or interface hardware failures cause a machine to be
inundated with garbage packets.
The scheme involves an exponential backoff where the input
side of the interface is disabled for longer and longer periods.
In the limiting case,
the interface is turned on every two minutes or so to see
if operation can resume.
.PP
In
.IR if_vv.h ,
you should define
NEW_BROADCAST
if the installation is running CTL boards which use the new broadcast
address of 0xff instead of the old address of 0.
In
.I if_vv.c
you should define
WIRECENTER
if you have a Wirecenter.
.PP
.BR N.B. :
the Wirecenter and broadcast address flags are
global and all ring interfaces
present are assumed to be identical in these two respects.
Moreover, an incorrect value of the Wirecenter #ifdef can
cause hardware damage.
.PP
The interface currently only supports the Internet protocol family
and provides both ``natural'' and ``trailer'' encapuslations.
There is a global variable in the driver code which determines
whether trailer encapsulations will be used for packets.
Currently,
this flag too is global so a mixed network
of trailer and non-trailer hosts isn't possible.
Several schemes are being considered for dealing with
this problem, but at the moment it is ``all or nothing.''
.SH DIAGNOSTICS
.PP
\fBvv%d: host %d\fP.  The software announces the host
address discovered during autoconfiguration.
.PP
\fBvv%d: can't initialize\fP. The software was unable to
discover the address of this interface, so it deemed
"dead" will not be enabled.
.PP
\fBvv%d: error vvocsr=%b\fP.  The hardware indicated an error on
the previous transmission.
.PP
\fBvv%d: output timeout\fP.  The token timer has fired and the
token will be recreated.
.PP
\fBvv%d: error vvicsr=%b\fP.  The hardware indicated an error
in reading a packet off the ring.
.PP
\fBen%d: can't handle af%d\fP.  The interface was handed
a message with addresses formatted in an unsuitable address
family; the packet was dropped.
.PP
\fBvv%d: vs_olen=%d\fP.  The ring output routine has been
handed a message with a preposterous length.  This results in
an immediate 
.IR "panic: vs_olen" .
.SH SEE ALSO
intro(4N), inet(4F)