baxter@ARGENTINE.ICS.UCI.EDU (Ira Baxter) (03/25/89)
I have two 6085 MFM miniscribes running on a WD controller. Can these be used with RLL controllers? I understand that RLL requires 7.5Mhz bit rate, and MFM is 5Mhz, but I hear rumors that in spite of this difference, the MFM drives tend to work anyway. What happens to drive reliability? Does anybody have experience with this, or should I just give up and get a bigger drive (RLL controllers MUCH cheaper than bigger drives!) IDB (714) 856-6693 ICS Dept/ UC Irvine, Irvine CA 92717
marc@rna.UUCP (Marc Johnson) (03/26/89)
In article <8903241748.aa12978@PARIS.ICS.UCI.EDU> baxter@ARGENTINE.ICS.UCI.EDU (Ira Baxter) writes: >I have two 6085 MFM miniscribes running on a WD controller. >Can these be used with RLL controllers? I understand that RLL >requires 7.5Mhz bit rate, and MFM is 5Mhz, but I hear rumors >that in spite of this difference, the MFM drives tend to work anyway. >What happens to drive reliability? Does anybody have experience >with this, or should I just give up and get a bigger drive >(RLL controllers MUCH cheaper than bigger drives!) > >IDB >(714) 856-6693 ICS Dept/ UC Irvine, Irvine CA 92717 I don't know a lot about the technical aspects, but the few questions I asked seemed to indicate that the quality of the platter media is the determining factor. RLL tries to squeeze about 1.5 times as much data per track as MFM, and the disk needs to be able to handle this. The technician I spoke to from Priam (my disk's manufacturere) assured me that they use the same media in their RLL and MFM drives--the RLL ones are simply tested and certified to run with RLL. I took the gamble and I'm running a Priam ID20 (24.5 Mbyte MFM) drive with an Adaptec RLL controller. And yes, sports fans, I'm getting the expected 37.6 MBytes. So far, no problems. The Priam guy told me that I'd be able to tell right away--it would either format without problems or it wouldn't. It's not a question, he said, of data disappearing or sectors becoming inaccessible over time. We'll see...it's been about 5 weeks now. I suggest you check with the manufacturer and try to get them to admit that their drive will handle RLL. If they won't, you still might want to take the gamble and get a cheap RLL controller and check it out. marc =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= = Marc Johnson BITNET: rna!marc@rockvax.bitnet = = Rockefeller Univ. Neurobiology UUCP: ...cmcl2!rna!marc = = New York City INTERNET: marc%rna@rocky2.rockefeller.edu = = (129.85.2.1) = = = = "Gimme the beat boys and free my soul, I wanna get lost in your rock & roll = = ...and drift away" = =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=