jdr@sloth.mlb.semi.harris.com (Jim Ray) (06/14/91)
Anyone know if the DSSI disks are SCSI ( or some form thereof )? If not, what type of interface do they use? Thanks, -- Jim Ray Harris Semiconductor Internet: jdr@semi.harris.com PO Box 883 MS 62B-022 Phone: (407) 729-5059 Melbourne, FL 32901
alan@shodha.enet.dec.com ( Alan's Home for Wayward Notes File.) (06/14/91)
In article <1991Jun13.200046.4932@mlb.semi.harris.com>, jdr@sloth.mlb.semi.harris.com (Jim Ray) writes: > Anyone know if the DSSI disks are SCSI ( or some form thereof )? DSSI is not SCSI, though at times it looks a lot like it. First the storage protocols used are MSCP for disks and TMSCP for tapes. As with SCSI each "device" on it has an imbedded disk or tape controller. The DSSI devices are called Integrate Storage Elements (ISEs). One way of looking at is that each ISE is a single drive HSC and the DSSI is the CI. > > If not, what type of interface do they use? Yet another DEC proprietary DSA thing. I suspect that people that designed looked at SCSI and decided they could do better. They probably use EDC/ECC instead of parity for data integrity on the bus. They may have extended the 6 meter cable limit or least made sure that all 6 meters is usable. If DSSI drives were closer to SCSI drives in price, I'd prefer them for storing my files. > > Thanks, You're welcome. > -- > Jim Ray Harris Semiconductor -- Alan Rollow alan@nabeth.cxn.dec.com
henderson@esvax.hamavnet.com (06/14/91)
In article <1991Jun13.200046.4932@mlb.semi.harris.com>, jdr@sloth.mlb.semi.harris.com (Jim Ray) writes: > Anyone know if the DSSI disks are SCSI ( or some form thereof )? No, they are not. > > If not, what type of interface do they use? They use DSSI interface. > > Thanks, You're welcome. -- Javier Henderson Engineering Services Avnet Computer Los Angeles, CA henderson@hamavnet.com {simpact,asylum,elroy,dhw68k}!hamavnet!henderson
braun@dri.com (Kral) (06/17/91)
In article <3372@shodha.enet.dec.com> alan@shodha.enet.dec.com ( Alan's Home for Wayward Notes File.) writes: > > If DSSI drives were closer to SCSI drives in price, I'd prefer > them for storing my files. Emulex is now making a line of DSSI compatible drives (DM series). We are in the process of purchasing one to add to our 4 RF71s. I'll post a summary after we've had a chance to test them out. Here is a comparison chart I got from my dealer (Pioneer): DEC EMULEX RF30 RF31 RF71 RF72 DM3760 DM3120 DM3160 capacity 150MB 381MB 400MB 1000MB 666MB 1036MB 1370MB avg acc. 29.4ms 23.6ms 29.3ms 21.7ms 18.2ms 23.3ms 17.0ms avg seek 21.0ms 15.3ms 21.0ms 13.4ms 11.9ms 15.0ms 11.5ms list $ $3250 $8500 $8500 $13,000 $6795 $8195 $8895 $/MB $21.67 $21.25 $18.99 $13.00 $10.20 $7.90 $6.49 [I see the RF31 and RF71 prices and $/MB don't make any sense, so you'll have to check this out for yourself]. -- kral * 408/647-6112 * ...!uunet!drivax!braun * braun@dri.com "Talking trash, touching on truth" -- Micheal Hedges "1-900-I-LUV-YOU"