DSSI: What was it like?

Bruce Lane <kyrrin(a)bluefeathertech.com> wrote: To which Chuck McManis <cmcmanis(a)mcmanis.com> replied: DEC lists in the manuals for both the DECsystem 5400 and the DECsystem 5500 as: "Digital Storage System Interconnect" and states: The DSSI bus has the following characteristics: A 4-Mbytes-per-second bandwidth Up to eight nodes Eight data lines One Parity line Eight control lines And gleened from somewhere a long time ago: One person wrote: :DSSI was developed from early SCSI definitions in an attempt to make :it robust, reliable and versatile (e.g. dual host option was defined :from the very beginning, while many of today's SCSI controllers still :can cope with only a single host adapter per bus). :The additional features made it more expensive then SCSI, and the :industry decided to go with the cheaper solution. Another person wrote: :> Are the two inter-changeable??? (SCSI vs DSSI) :No. It's interesting, though, that there were vendors whose storage :controllers had host ports that were software configurable as either :DSSI or SCSI. I never got close enough to one of these to find out :if they used the same signal wiring, though [most likely not - it is :conceivable that logic levels were compatible enough that one could :use the same line drivers and receivers, but they would still have had :to have a way to choose connectors that matched the interface type]. FWIW Mike