[comp.edu] SMD Interface standard

curry@nsc.nsc.com (Ray Curry) (09/12/88)

I was wondering if some sole out there could point me to the keeper of 
the SMD drive interface standard.  I know that the SCSI is now an 
ANSI standard, but don't seem to be able to find SMD listed anywhere.
Is it really a standard or just a widely adopted industry pattern?

johnl@ima.ima.isc.com (John R. Levine) (09/13/88)

In article <6290@nsc.nsc.com> curry@nsc.UUCP (Ray Curry) writes:
>I was wondering if some sole out there could point me to the keeper of 
>the SMD drive interface standard.  I know that the SCSI is now an 
>ANSI standard, but don't seem to be able to find SMD listed anywhere.

SMD is ANSI standard X2.91M-1982.  The standard was promulgated fairly
late in the life of SMD interfaces, so it attempted to codify existing
practice rather than creating a clean standard, so for example it only
defines 10 cylinder address lines limiting standard SMD drives to 1K
cylinders.
-- 
John R. Levine, IECC, PO Box 349, Cambridge MA 02238-0349, +1 617 492 3869
{ bbn | think | decvax | harvard | yale }!ima!johnl, Levine@YALE.something
Rome fell, Babylon fell, Scarsdale will have its turn.  -G. B. Shaw

seeger@beach.cis.ufl.edu (F. L. Charles Seeger III) (09/13/88)

In article <2595@ima.ima.isc.com> johnl@ima.UUCP (John R. Levine) writes:
|In article <6290@nsc.nsc.com> curry@nsc.UUCP (Ray Curry) writes:
|>I was wondering if some sole out there could point me to the keeper of 
|>the SMD drive interface standard.
|
|SMD is ANSI standard X2.91M-1982.  The standard was promulgated fairly
|late in the life of SMD interfaces, so it attempted to codify existing
|practice rather than creating a clean standard, so for example it only
|defines 10 cylinder address lines limiting standard SMD drives to 1K
|cylinders.
|-- 
|John R. Levine, IECC, PO Box 349, Cambridge MA 02238-0349, +1 617 492 3869

Can anyone fill us in on SMD-E, 2.4 and 3.0 MBps interfaces, etc?  Are
there new high performance disk interfaces on the horizon that we should
be aware of?  I've heard of work being done on simultaneous reading from
all (or some subset > 1) of the tracks of a cylinder.  What interface
could handle that much bandwidth?

Thanks in advance,
Chuck  (seeger@beach.cis.ufl.edu)

frazier@oahu.cs.ucla.edu (Greg Frazier) (09/13/88)

In article <6290@nsc.nsc.com> curry@nsc.UUCP (Ray Curry) writes:
>I was wondering if some sole out there could point me to the keeper of 
			 ^^^^
>the SMD drive interface standard.  I know that the SCSI is now an 

I wasn't aware that they had put fish in charge of the interface
standards - why is it the creatures in charge are all cold-blooded
these days (and scaly to boot :-)!


sorry - couldn't resist
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Greg Frazier	    o	Internet: frazier@CS.UCLA.EDU
CS dept., UCLA	   /\	UUCP: ...!{ucbvax,rutgers}!ucla-cs!frazier
	       ----^/----
		   /

lamaster@ames.arc.nasa.gov (Hugh LaMaster) (09/14/88)

In article <2595@ima.ima.isc.com> johnl@ima.UUCP (John R. Levine) writes:
>In article <6290@nsc.nsc.com> curry@nsc.UUCP (Ray Curry) writes:
>>I was wondering if some sole out there could point me to the keeper of 
>>the SMD drive interface standard.  I know that the SCSI is now an 

>SMD is ANSI standard X2.91M-1982.  The standard was promulgated fairly

Also FIPS PUB 111, which has some significance for Federal Govt. users
and suppliers, since Federal Procurement regulations require "large"
(large minicomputers on up) systems to have either FIPS 6x ("IBM")
channel connections or FIPS 111 (SMD).




-- 
  Hugh LaMaster, m/s 233-9,  UUCP ames!lamaster
  NASA Ames Research Center  ARPA lamaster@ames.arc.nasa.gov
  Moffett Field, CA 94035     
  Phone:  (415)694-6117