1.\" $NetBSD: dmc.4,v 1.9 2001/07/08 17:22:54 wiz Exp $ 2.\" 3.\" Copyright (c) 1983, 1991, 1993 4.\" The Regents of the University of California. All rights reserved. 5.\" 6.\" Redistribution and use in source and binary forms, with or without 7.\" modification, are permitted provided that the following conditions 8.\" are met: 9.\" 1. Redistributions of source code must retain the above copyright 10.\" notice, this list of conditions and the following disclaimer. 11.\" 2. Redistributions in binary form must reproduce the above copyright 12.\" notice, this list of conditions and the following disclaimer in the 13.\" documentation and/or other materials provided with the distribution. 14.\" 3. All advertising materials mentioning features or use of this software 15.\" must display the following acknowledgement: 16.\" This product includes software developed by the University of 17.\" California, Berkeley and its contributors. 18.\" 4. Neither the name of the University nor the names of its contributors 19.\" may be used to endorse or promote products derived from this software 20.\" without specific prior written permission. 21.\" 22.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32.\" SUCH DAMAGE. 33.\" 34.\" from: @(#)dmc.4 8.1 (Berkeley) 6/5/93 35.\" 36.Dd June 5, 1993 37.Dt DMC 4 vax 38.Os 39.Sh NAME 40.Nm dmc 41.Nd 42.Tn DEC 43.Tn DMC-11 Ns / Tn DMR-11 44point-to-point serial communications device 45.Sh SYNOPSIS 46.Cd "dmc0 at uba0 csr 167600" 47.Sh DESCRIPTION 48The 49.Nm dmc 50interface provides access to a point-to-point communications 51device which runs at either 1 Mb/s or 56 Kb/s. 52.Tn DMC-11 Ns s 53communicate 54using the 55.Tn DEC DDCMP 56link layer protocol. 57.Pp 58The 59.Nm dmc 60interface driver also supports a 61.Tn DEC 62.Tn DMR-11 63providing point-to-point 64communication running at data rates from 2.4 Kb/s to 1 Mb/s. 65.Tn DMR-11 Ns s 66are a more recent design and thus are preferred over 67.Tn DMC-11 Ns s . 68The 69.Dv NXMT 70and 71.Dv NRCV 72constants in the driver may be increased in this case, 73as the 74.Tn DMR 75can accept up to 64 transmit and receive buffers, as opposed 76to 7 for the 77.Tn DMC . 78.Pp 79The configuration flags specify how to set up the device, 80.Bl -column xxx -offset indent 810 full duplex DDCMP (normal mode) 821 DDCMP Maintenance mode (generally useless) 832 DDCMP Half Duplex, primary station 843 DDCMP Half Duplex, secondary station 85.El 86.Pp 87The host's address must be specified with an 88.Dv SIOCSIFADDR 89.Xr ioctl 2 , 90and the destination address specified with a 91.Dv SIOCSIFDSTADDR 92.Xr ioctl 2 , 93before the interface will transmit or receive any packets. 94.Sh ROUTING 95The driver places a 96.Tn HOST 97entry in the kernel routing tables for the 98address given in the 99.Dv SIOCSIFDSTADDR 100.Xr ioctl 2 . 101To use the 102.Tn DMC 103as a 104link between local nets, the route to the remote net must be added manually 105with the 106.Xr route 8 107command, or by the use of the routing process 108.Xr routed 8 109on each end of the link. 110.Sh DIAGNOSTICS 111.Bl -diag 112.It dmc%d: bad control %o. 113A bad parameter was passed to the 114.Em dmcload 115routine. 116.Pp 117.It dmc%d: unknown address type %d. 118An input packet was received which contained a type of 119address unknown to the driver. 120.Pp 121.It DMC fatal error 0%o. 122A fatal error in 123.Tn DDMCP 124occurred, causing the device to be restarted. 125.Pp 126.It DMC soft error 0%o. 127A non-fatal error in 128.Tn DDMCP 129has occurred. 130.Pp 131.It dmc%d: af%d not supported. 132The interface was handed a message which has 133addresses formatted in an unsuitable address family. 134.El 135.Sh SEE ALSO 136.Xr intro 4 , 137.Xr inet 4 138.Sh HISTORY 139The 140.Nm 141driver appeared in 142.Bx 4.2 . 143.Sh BUGS 144The current version of the driver uses a link-level encapsulation 145so that multiple protocol types may be used. 146It is thus incompatible with earlier drivers, 147including the 148.Bx 4.2 149version. 150