dmv.4

来自「<B>Digital的Unix操作系统VAX 4.2源码</B>」· 4 代码 · 共 185 行

.TH dmv 4
.SH Name
dmv \- DMV11 communications interface
.SH Syntax
.B "device dmv0 at uba0 csr 0167600 flags 0x???? vector dmvrint dmvxint"
.SH Description
.NXS "dmv interface" "DMV11 communications interface"
.NXR "DMV11 communications interface"
The
.PN dmv
interface provides access to point-to-point communications 
that runs at speeds from 2.4 Kb/s to 56 Kb/s.
DMV11s communicate using the DDCMP link layer protocol.
.PP
Several protocols can be multiplexed over a
.PN dmv
link simultaneously.  Conversely, a 
.PN dmv
can be set up so that only one protocol family can use that device.
If the latter approach is taken, an SIOCSTATE ioctl must be issued
by the protocol family requesting device ownership.  The family's
address must appear in the ``if_family'' structure member, and
``if_nomuxhdr'' must be set.  Before requesting ownership, be
sure to disable access to the device for all other protocol families.
.PP
The first byte of the 
.PN flags 
word can be set up to indicate what mode
the device should use.
If bit 0 is clear, the device operates in point-to-point DDCMP mode;
otherwise, it operates in maintenance mode.  If bit 1 is clear, the
device operates in full duplex mode; otherwise, it operates in half
duplex.  If bit 2 is clear, the device operates in  
.PN dmc
compatibility mode; otherwise, it operates using
version 4.0 of the DDCMP protocol.
The number of outstanding transmit buffers can be increased from
a default of 7 to a maximum of 24 buffers by specifying a
hexadecimal value in the second byte of the 
.PN flags 
word.
For example, if 
.PN flags 
is set to 0x1800, 24 transmit
buffers will be allocated on a device set up to run full
duplex in
.PN dmc
compatibility mode.
.SH Restrictions
Note that maintenance mode should only be used to diagnose data link problems.
It is not intended to be used for normal data link traffic.
.PP
If specifying maintenance mode, do not set bit 2 of the 
.PN flags 
word.
.SH Diagnostics
.B "dmvprobe: can't start device" 
.br
The 
.PN dmv
could not be started at boot time.
.PP
.B "dmvprobe: device failed diagnostics, octal failure code = %o"
.br 
The 
.PN dmv
failed diagnostics at boot time.
.PP
.B "dmvinit: can't place dmv%d into internal loopback"
.br 
Unable to place the
.PN dmv
into internal loopback requested by user.
.PP
.B "dmv%d: done unalloc rbuf"
.br 
The device returned a receive or transmit buffer that was
not allocated to it.
.PP
.B "dmv%d: unknown address type %d"
.br 
An input packet was received that contained a type of
address uknown to the driver.
.PP
.B "dmv%d bad packet address 0x%x"
.br 
The device returned a buffer with an unexpected buffer address.
.PP
.B "dmv%d: unsolicited information response: ctl = %x, data = %x"
.br 
The device interrupted the driver with an information response
when none was requested.
.PP
.B "dmvd%d: bad control %o"
.br 
A bad parameter was passed to the dmvload routine.
.PP
.B "dmv%d: modem disconnect"
.br 
The modem disconnected, or there was a loss of carrier
while a packet was being received.
.PP
.B "dmv%d: buffer too small"
.br 
The remote node sent a packet that was too large to fit in
the allocated receive buffer.
.PP
.B "dmv%d: receive threshold reported"
.br 
The
.PN dmv
reported a receive threshold error.
.PP
.B "dmv%d: transmit threshold reached"
.br 
The
.PN dmv
reported a transmit threshold error.
.PP
.B "dmv%d: select threshold reached"
.br 
The
.PN dmv
reported a select threshold error.
.PP
.B "dmv%d: babbling tributary reported"
.br 
The
.PN dmv
reported a babbling tributary error.
.PP
.B "dmv%d: streaming tributary reported"
.br 
The
.PN dmv
reported a streaming tributary error.
.PP
.B "dmv%d: MOP mode entered while DDCMP was running"
.br 
.B "dmv%d: MOP mode entered while device was halted" 
.br
The
.PN dmv
has entered MOP mode.
.PP
.B "dmv%d: non existent memory reported"
.br 
The
.PN dmv
accessed non-existent memory.
.PP
.B "dmv%d: device queue overflow reported"
.br 
The
.PN dmv
reported a queue overflow.
.PP
.B "dmv%d: invalid counter pointer"
.br 
The
.PN dmv
is reporting the contents of a counter when no request
was made to do so.
.PP
.B "dmv%d: can't handle af%d"
.br 
The
.PN dmv
was handed a transmit message that has addresses formatted
in an unsuitable address family.
.PP
.B "dmv%d: internal loopback enable requested"
.br 
The device is being put in internal loopback at a user's
request.
.PP
.B "dmv%d: internal loopback disable requested"
.br 
The device is being taken out of internal loopback at a user's
request.
.PP
.B "dmvwatch: dmv%d hung, bse10=%b, bsell = %b, bse12=%b"
.br 
The device has not responded after a long period of time.