VAX 4000 Model 108 User Information E-1
E
Programming Parameters for DSSI
Devices
This appendix describes the console mode procedures for setting and examining
parameters for DSSI devices.
__________________________ Note _____________________________
Before you reprogram DSSI devices, you should have a good understanding of DSSI
architecture and VAXcluster software operation. If you do not have that understanding,
you should read the VMS manuals which came with your system or call your Digital
service representative.
____________________________________________________________
On VAX 4000 Model 108 systems, an embedded DSSI adapter provides the interface
between the CPU and the DSSI storage devices.
The KFDDA-BB daughter card adapter provides a DSSI bus that can support up to eight
nodes, where the adapter and each DSSI storage device count as one node, hence each
DSSI adapter can support up to seven DSSI storage devices (six DSSI storage devices for a
two-system DSSI VAXcluster configuration; five DSSI storage devices for a three-system
DSSI VAXcluster configuration). The adapter makes a connection between the CPU and
the requested device on the respective DSSI bus. Each DSSI device has its own controller
and server that contain the intelligence and logic necessary to control data transfers over
the DSSI bus.
