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@(#)dmc.4 6.4 (Berkeley) 01/30/87
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 may 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/lib/adb/dmcstats, or the DMC11 technical 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.
"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.