X-Git-Url: https://git.subgeniuskitty.com/unix-history/.git/blobdiff_plain/0f4556f12c8f75078501c9d1338ae7648a97f975..95f51977ddc18faa2e212f30c00a39540b39f325:/usr/man/man4/ec.4

diff --git a/usr/man/man4/ec.4 b/usr/man/man4/ec.4
index 9fb10fdad2..c1f55177f4 100644
--- a/usr/man/man4/ec.4
+++ b/usr/man/man4/ec.4
@@ -1,9 +1,15 @@
-.TH EC 4 "27 July 1983"
-.UC  4
+.\" Copyright (c) 1983 Regents of the University of California.
+.\" All rights reserved.  The Berkeley software License Agreement
+.\" specifies the terms and conditions for redistribution.
+.\"
+.\"	@(#)ec.4	6.4 (Berkeley) 5/16/86
+.\"
+.TH EC 4 "May 16, 1986"
+.UC 5
 .SH NAME
 ec \- 3Com 10 Mb/s Ethernet interface
 .SH SYNOPSIS
-.B "device ec0 at uba0 csr 161000 vector ecrint eccollide ecxint"
+.B "device ec0 at uba0 csr 161000 vector ecrint eccollide ecxint flags 0"
 .SH DESCRIPTION
 The
 .I ec
@@ -14,8 +20,12 @@ The hardware has 32 kilobytes of dual-ported memory on the UNIBUS.
 This memory
 is used for internal buffering by the board, and the interface code reads
 the buffer contents directly through the UNIBUS.
+The address of this memory is given in the \fIflags\fP field
+in the configuration file.
+The first interface normally has its memory at Unibus address 0.
 .PP
-The host's Internet address is specified at boot time with an SIOCSIFADDR
+Each of the host's network addresses
+is specified at boot time with an SIOCSIFADDR
 ioctl.  The
 .I ec
 interface employs the address resolution protocol described in
@@ -23,6 +33,13 @@ interface employs the address resolution protocol described in
 to dynamically map between Internet and Ethernet addresses on the local
 network.
 .PP
+The interface normally tries to use a ``trailer'' encapsulation
+to minimize copying data on input and output.
+The use of trailers is negotiated with ARP.
+This negotiation may be disabled, on a per-interface basis,
+by setting the IFF_NOTRAILERS
+flag with an SIOCSIFFLAGS ioctl.
+.PP
 The interface software implements an exponential backoff algorithm
 when notified of a collision on the cable.  This algorithm utilizes
 a 16-bit mask and the VAX-11's interval timer in calculating a series
@@ -37,17 +54,15 @@ up.
 .TP 5
 3.
 Shift the mask left one bit and formulate a backoff by
-masking the interval timer with the mask (this is actually
-the two's complement of the value).
+masking the interval timer with the smaller of the complement of this mask
+and a 5-bit mask, resulting in a pseudo-random number between 0 and 31.
+This produces the number of slot times to delay,
+where a slot is 51 microseconds.
 .TP 5
 4.
 Use the value calculated in step 3 to delay before retransmitting
-the packet.  The delay is done in a software busy loop.
-.PP
-The interface normally tries to use a ``trailer'' encapsulation
-to minimize copying data on input and output.  This may be
-disabled, on a per-interface basis, by setting the IFF_NOTRAILERS
-flag with an SIOCSIFFLAGS ioctl.
+the packet.
+The delay is done in a software busy loop.
 .SH DIAGNOSTICS
 .BR "ec%d: send error" .
 After 16 retransmissions using the
@@ -66,8 +81,6 @@ family; the packet was dropped.
 .SH SEE ALSO
 intro(4N), inet(4F), arp(4P)
 .SH BUGS
-The PUP protocol family should be added.
-.PP
 The hardware is not capable of talking to itself.  The software
 implements local sending and broadcast by sending such packets to the
 loop interface.  This is a kludge.