Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!wuarchive!zaphod.mps.ohio-state.edu!uakari.primate.wisc.edu!aplcen!boingo.med.jhu.edu!haven!ni.umd.edu!MIKE@UC780.UMD.EDU From: mike@UC780.UMD.EDU (Mike Santangelo) Newsgroups: comp.sys.dec Subject: Re: hard drives for q-bus Message-ID: <1991Apr15.190345.5198@ni.umd.edu> Date: 15 Apr 91 19:03:45 GMT References: <1991Apr11.114144.79@ulkyvx.bitnet> Sender: usenet@ni.umd.edu (USENET News System) Reply-To: mike@UC780.UMD.EDU Organization: The University of Maryland, University College Lines: 27 Nntp-Posting-Host: uc780.umd.edu 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) +