pcl
—
DEC CSS PCL-11 B Network Interface
pcl0 at uba? csr 164200 vector pclxint pclrint
NOTE: This driver has not been ported from 4.4BSD yet.
The pcl
device provides an IP-only
interface to the DEC CSS PCL-11 time division multiplexed network bus. The
controller itself is not accessible to users.
The host's address is specified with the
SIOCSIFADDR
ioctl(2). The interface will
not transmit or receive any data before its address is defined.
As the PCL-11 hardware is only capable of having 15 interfaces per
network, a single-byte host-on-network number is used, with range [1..15] to
match the TDM bus addresses of the interfaces.
The interface currently only supports the Internet protocol family
and only provides “natural” (header) encapsulation.
- pcl%d: can't init.
- Insufficient UNIBUS resources existed to initialize the device. This is
likely to occur when the device is run on a buffered data path on an
11/750 and other network interfaces are also configured to use buffered
data paths, or when it is configured to use buffered data paths on an
11/730 (which has none).
- pcl%d: can't handle af%d.
- The interface was handed a message with addresses formatted in an
unsuitable address family; the packet was dropped.
- pcl%d: stray xmit interrupt.
- An interrupt occurred when no output had previously been started.
- pcl%d: master.
- The TDM bus had no station providing ``bus master'' timing signals, so
this interface has assumed the ``master'' role. This message should only
appear at most once per UNIBUS INIT on a single system. Unless there is a
hardware failure, only one station may be master at a time.
- pcl%d: send error, tcr=%b, tsr=%b.
- The device indicated a problem sending data on output. If a ``receiver
offline'' error is detected, it is not normally logged unless the option
PCL_TESTING
has been selected, as this causes a
lot of console chatter when sending to a down machine. However, this
option is quite useful when debugging problems with the PCL
interfaces.
- pcl%d: rcv error, rcr=%b rsr=%b.
- The device indicated a problem receiving data on input.
- pcl%d: bad len=%d.
- An input operation resulted in a data transfer of less than 0 or more than
1008 bytes of data into memory (according to the word count register).
This should never happen as the maximum size of a PCL message has been
agreed upon to be 1008 bytes (same as ARPANET message).
The pcl
interface appeared in
4.2BSD.