kpjone01@ulkyvx.bitnet (04/11/91)
Is there any way to hook a standard rll or mfm hard drive up to a Q-bus machine? Kevin kpjone01@ulkyvx.bitnet
kalisiak@acsu.buffalo.edu (christophe m kalisiak) (04/13/91)
In article <1991Apr11.114144.79@ulkyvx.bitnet> kpjone01@ulkyvx.bitnet writes: >Is there any way to hook a standard rll or mfm hard drive up to a Q-bus >machine? Yes. Buy a Q-Bus controller which will accept RLL or MFM drives. Emulex and Dilog have them. (Are they ST506 drives?) P.S. Have you had a chance to check out the disk packs yet? Chris Kalisiak V076N3W7@ubvms.cc.buffalo.edu kalisiak@acsu.buffalo.edu
mike@UC780.UMD.EDU (Mike Santangelo) (04/16/91)
In article <1991Apr11.114144.79@ulkyvx.bitnet>, kpjone01@ulkyvx.bitnet writes: >Is there any way to hook a standard rll or mfm hard drive up to a Q-bus >machine? > >Kevin >kpjone01@ulkyvx.bitnet Well, the DEC RQDX3 uses MFM & ST506 connections, but the drive types for 2 drives (RD53 and RD54, dunno about RD52) are hardcoded in ROM on the board. These are really just off-she-shelf ST506 hard disks from QUANTUM and MAXTOR (well, DEC tweaked the motor power control on one I beleive to let it ramp up to speed more slowly to ease the power supply). One thing you do have to realize though is that MFM/RLL( and thus I presume you mean ST506 drives) are going to be ALOT SLOWER than more recent technologies (ESDI, SCSI) or well-established high performance interfaces (SMD, IPI). The ST506 interface can only go so fast, the best I have seen it do is 500KB/sec which is miserable for a multiuser system. If you can ESDI or SCSI drives, by far all the better. +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Michael F. Santangelo + Inet: mike@uc780.umd.edu VMS / UNIX Systems + mike@socrates.umd.edu Academic Computing UMUC + Bnet: MIKE@UC780 (The University of Maryland, + MIKE@UMUC (not visited often) University College) +<Your clever net-phrase here>
terry@spcvxb.spc.edu (Terry Kennedy, Operations Mgr.) (04/16/91)
In article <1991Apr15.190345.5198@ni.umd.edu>, mike@UC780.UMD.EDU (Mike Santangelo) writes: > Well, the DEC RQDX3 uses MFM & ST506 connections, but the drive types > for 2 drives (RD53 and RD54, dunno about RD52) are hardcoded in ROM > on the board. These are really just off-she-shelf ST506 hard disks > from QUANTUM and MAXTOR (well, DEC tweaked the motor power control on > one I beleive to let it ramp up to speed more slowly to ease the power > supply). Just to set the record straight - the RQDX3 writes the drive geometry information to the disk when it is first formatted. After that, the disk- resident copy is used. The RQDX3 can support user-defined geometries as well, but you need to be _very_ familiar with the way DEC does MSCP. The RD54 is a modified Maxtor XT-2190, the 53 is a modified Micropolis 1325, the 52 is either a Quantum Q540 or an Atasi 3046, but _never_ an Evotek 5540 [That's an in joke], and the 51 is an ST-412. Terry Kennedy Operations Manager, Academic Computing terry@spcvxa.bitnet St. Peter's College, US terry@spcvxa.spc.edu (201) 915-9381
mike@UC780.UMD.EDU (Mike Santangelo) (04/17/91)
In article <1991Apr16.055810.1249@spcvxb.spc.edu>, terry@spcvxb.spc.edu (Terry Kennedy, Operations Mgr.) writes: >In article <1991Apr15.190345.5198@ni.umd.edu>, mike@UC780.UMD.EDU (Mike Santangelo) writes: > >> Well, the DEC RQDX3 uses MFM & ST506 connections, but the drive types >> for 2 drives (RD53 and RD54, dunno about RD52) are hardcoded in ROM >> on the board. These are really just off-she-shelf ST506 hard disks >> from QUANTUM and MAXTOR (well, DEC tweaked the motor power control on >> one I beleive to let it ramp up to speed more slowly to ease the power >> supply). > > Just to set the record straight - the RQDX3 writes the drive geometry >information to the disk when it is first formatted. After that, the disk- >resident copy is used. The RQDX3 can support user-defined geometries as >well, but you need to be _very_ familiar with the way DEC does MSCP. > I stand corrected. Now, do you or anybody you know - know of a utility that could write this info given simply #heads and #cylinders? > The RD54 is a modified Maxtor XT-2190, the 53 is a modified Micropolis >1325, the 52 is either a Quantum Q540 or an Atasi 3046, but _never_ an >Evotek 5540 [That's an in joke], and the 51 is an ST-412. > > Terry Kennedy Operations Manager, Academic Computing > terry@spcvxa.bitnet St. Peter's College, US > terry@spcvxa.spc.edu (201) 915-9381 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Michael F. Santangelo + Inet: mike@uc780.umd.edu VMS / UNIX Systems + mike@socrates.umd.edu Academic Computing UMUC + Bnet: MIKE@UC780 (The University of Maryland, + MIKE@UMUC (not visited often) University College) +<Your clever net-phrase here>