4.3BSD - /usr/man/cat4/acc.0

ACC(4)                                                                  ACC(4)


NAME
       acc - ACC LH/DH IMP interface

SYNOPSIS
       pseudo-device imp
       device acc0 at uba0 csr 167600 vector accrint accxint

DESCRIPTION
       The  acc 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
       hardware support to the IMP interface described in imp(4).   When  con‐
       figuring, the imp pseudo-device must also be included.

DIAGNOSTICS
       acc%d:  not  alive.  The initialization routine was entered even though
       the device did not autoconfigure.  This indicates a system problem.

       acc%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).

       acc%d: imp doesn’’t respond, icsr=%b.  The driver attempted to  initial‐
       ize  the  device, but the IMP failed to respond after 500 tries.  Check
       the cabling.

       acc%d: stray xmit interrupt, csr=%b.  An  interrupt  occurred  when  no
       output had previously been started.

       acc%d:  output error, ocsr=%b, icsr=%b.  The device indicated a problem
       sending data on output.

       acc%d: input error, csr=%b.  The device indicated a  problem  receiving
       data on input.

       acc%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.


4.2 Berkeley Distribution        May 15, 1985                           ACC(4)