On Thu, Aug 29, 2019, 9:27 PM Alan Perry via cctalk <cctalk@classiccmp.org> wrote:
> > > On 8/29/19 9:17 PM, Glen Slick via cctalk wrote: > > On Thu, Aug 29, 2019 at 4:53 PM Alan Perry via cctalk > > <cctalk@classiccmp.org> wrote: > >> > >> My Sun 3/260 came with a pair of 8-inch SMD disks in a separate cabinet. > >> > >> 1. Anyone have a pointer to docs that describe cabling and configuring > >> SMD disks? My Google-fu has failed here. > >> > >> 2. The system came with no cables (external cables between cabinets). > >> Are these standard cables or will they be Sun-specific? > >> > >> 3. The system "ran when parked" about a dozen years ago, but it was left > >> in an open barn after that. How likely is it that the disks will work > >> and be readable? One is a Fujitsu M2333; don't recall what they other > >> one is. > >> > >> alan > > > > It has been over 5 years now since I had a Sun 4/280. I gave that away > > to someone else on the list. > > > > That system had an Xylogics 7053 SMD controller with a couple of > > Hitachi 900MB DK815-10 SMD-E ~8-inch drives. I forget the details now. > > From a quick look online the Xylogics 7053 SMD controller has a CMD > > port, and a DATA 0,1 and a DATA 2,3 port. If I remember right the CMD > > port was cabled to the CMD in port of the first drive, then the CMD > > out port of the first drive was cabled to the CMD in port of the > > second drive, then the CMD out port of the second drive was > > terminated. The DATA 0,1 port must have had a Y-cable that was split > > to the DATA ports of each drive. > > On the controller side, there are two command connectors, one wider than > the other, as well as two data connectors. On the disk cabinet side, > there is a connector marked 'data 0', connected to one HDD, another > marked 'data 1', connected to the other HDD, and two pairs of command > connectors, one marked 'in' and the other 'out'. I haven't yet followed > the command cabling to see what the connectors connect to. > > > > > There were other Xylogics SMD controllers as well. Which controller do > > you have in your system? > > Xylogics 451. > The diagram on this page it shows that the 60-pin SMD Command connector of the Xylogics 461 is split into two connectors on the bulkhead panel: http://shrubbery.net/~heas/sun-feh-2_1/Systems/Sun3/DISK_53_Xylogics-451.html My guess is that it was easier in some way to have two smaller connectors and cables than a single larger connector and cable. I can't remember now if the Xylogics 7053 did the same thing with split Command cables. I assume that in the disk cabinet the two Command In connectors join back into a standard 60-pin SMD Control connection to the first disk, which is then chained to the second disk, which is the chained and split again to the two Command Out connectors. >
