CSS(4) BSD/vax Kernel Interfaces Manual CSS(4)NAMEcss — DEC IMP-11A LH/DH IMP interface
pseudo-device imp device css0 at uba0 csr 167600 flags 10 vector cssrint
The css device provides a Local Host/Distant Host interface to an IMP.
It is normally used when participating in the DARPA Internet. The con‐
troller itself is not accessible to users, but instead provides the hard‐
ware support to the IMP interface described in imp(4). The configuration
entry for the imp must also include the pseudo-device as shown above.
css%d: not alive. The initialization routine was entered even though the
device did not autoconfigure. This is indicates a system problem.
css%d: can't initialize. Insufficient UNIBUS resources existed to ini‐
tialize 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).
css%d: imp doesn't respond, icsr=%b. The driver attempted to initialize
the device, but the IMP failed to respond after 500 tries. Check the
css%d: stray output interrupt csr=%b. An interrupt occurred when no out‐
put had previously been started.
css%d: output error, ocsr=%b icsr=%b. The device indicated a problem
sending data on output.
css%d: recv error, csr=%b. The device indicated a problem receiving data
css%d: bad length=%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
host-IMP message is 1008 bytes.
The css interface appeared in 4.2BSD.
4.2 Berkeley Distribution June 5, 1993 4.2 Berkeley Distribution