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dmc(4) [bsd man page]

DMC(4)							     Kernel Interfaces Manual							    DMC(4)

NAME
dmc - DEC DMC-11/DMR-11 point-to-point communications device SYNOPSIS
/sys/conf/SYSTEM: NDMC dmc_controllers # DMC11 DESCRIPTION
The dmc interface provides access to a point-to-point communications device which runs at either 1 Mb/s or 56 Kb/s. DMC-11's communicate using the DEC DDCMP link layer protocol. The dmc interface driver also supports a DEC DMR-11 providing point-to-point communication running at data rates from 2.4 Kb/s to 1 Mb/s. DMR-11's are a more recent design and thus are preferred over DMC-11's. The NXMT and NRCV constants in the driver should be increased in this case, as the DMR can accept up to 64 transmit and receive buffers, as opposed to 7 for the DMC. The configuration flags specify how to set up the device, 0 -- full duplex DDCMP (normal mode) 1 -- DDCMP Maintence mode (generally useless) 2 -- DDCMP Half Duplex, primary station 3 -- DDCMP Half Duplex, secondary station Several device error counters are available via "adb", for more information see the adb script /usr/share/adb/dmcstats, or the DMC11 tech- nical manual. The host's address must be specified with an SIOCSIFADDR ioctl, and the destination address specified with a SIOCSIFDSTADDR ioctl, before the interface will transmit or receive any packets. ROUTING
The driver places a HOST entry in the kernel routing tables for the address given in the SIOCSIFDSTADDR ioctl. To use the DMC as a link between local nets, the route to the remote net must be added manually with the route(8) command, or by the use of the routing process routed(8) on each end of the link. DIAGNOSTICS
dmc%d: bad control %o. A bad parameter was passed to the dmcload routine. dmc%d: unknown address type %d. An input packet was received which contained a type of address unknown to the driver. DMC fatal error 0%o. A fatal error in DDMCP occurred, causing the device to be restarted. DMC soft error 0%o. A non-fatal error in DDMCP has occurred. dmc%d: af%d not supported. The interface was handed a message which has addresses formatted in an unsuitable address family. SEE ALSO
intro(4N), inet(4F) BUGS
The current version of the driver uses a link-level encapsulation so that multiple protocol types may be used. It is thus incompatible with earlier drivers, including the 4.2BSD version. 3rd Berkeley Distribution October 22, 1996 DMC(4)

Check Out this Related Man Page

TXP(4)							   BSD Kernel Interfaces Manual 						    TXP(4)

NAME
txp -- 3Com 3XP Typhoon/Sidewinder (3CR990) Ethernet interface SYNOPSIS
To compile this driver into the kernel, place the following line in your kernel configuration file: device txp Alternatively, to load the driver as a module at boot time, place the following line in loader.conf(5): if_txp_load="YES" DESCRIPTION
The txp interface provides access to the 10Mb/s and 100Mb/s Ethernet networks via the 3Com Typhoon/Sidewinder chipset. Basic Ethernet functions are provided as well as support for vlan(4) tag removal and insertion assistance, receive ip(4), tcp(4), and udp(4) checksum offloading, and transmit ip(4) checksum offloading. There is currently no support for transmit tcp(4) or udp(4) checksum offload- ing, tcp(4) segmentation, nor ipsec(4) acceleration. Each of the host's network addresses is specified at boot time with an SIOCSIFADDR ioctl(2). The txp interface employs the address resolu- tion protocol described in arp(4) to dynamically map between Internet and Ethernet addresses on the local network. When a txp interface is brought up, by default, it will attempt to auto-negotiate the link speed and duplex mode. The speeds, in order of attempt, are: 100Mb/s Full Duplex, 100Mb/s Half Duplex, 10 Mb/s Full Duplex, and 10 Mb/s Half Duplex. The txp supports several media types, which are selected via the ifconfig(8) command. The supported media types are: media autoselect Attempt to autoselect the media type (default) media 100baseTX mediaopt full-duplex Use 100baseTX, full duplex media 100baseTX [mediaopt half-duplex] Use 100baseTX, half duplex media 10baseT mediaopt full-duplex Use 10baseT, full duplex media 10baseT [mediaopt half-duplex] Use 10baseT, half duplex HARDWARE
The txp driver supports the following cards: o 3Com 3CR990-TX-95 o 3Com 3CR990-TX-97 o 3Com 3cR990B-TXM o 3Com 3CR990SVR95 o 3Com 3CR990SVR97 o 3Com 3cR990B-SRV SEE ALSO
altq(4), arp(4), inet(4), intro(4), ip(4), miibus(4), tcp(4), udp(4), vlan(4), ifconfig(8) HISTORY
The txp driver first appeared in OpenBSD 2.9. BSD
March 12, 2009 BSD

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