sophist@brainiac.raidernet.com (Phillip McReynolds) (02/13/91)
I have probably seen this question before but did not write the answer down at the time. My apologies. (Is there a FAQ file for this group, I wonder?) Is it possible to have both an RLL drive+controller & a SCSI drive+controller inhabiting the same machine? If it *is* possible, are there any problems which might make such a scheme either troublesome or unreliable? Regards, Phillip McReynolds = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = Phillip A. McReynolds, sophist@brainiac.raidernet.com Licensed Philosopher org: Phillip's Philosophy Shop, Inc. (MPA Certified) "Quality Philosophy Products Since 1990" #include BiFF's_.sig = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = =
jdb@reef.cis.ufl.edu (Brian K. W. Hook) (02/14/91)
In article <7yy0w2w163w@brainiac.raidernet.com> sophist@brainiac.raidernet.com (Phillip McReynolds) writes: >Is it possible to have both an RLL drive+controller & a SCSI >drive+controller inhabiting the same machine? If it *is* possible, are >there any problems which might make such a scheme either troublesome or >unreliable? According to the lady I talked to at Hard Drives International any "non intelligent drive adapter can coincide just fine with an intelligent adapter". She stated that a SCSI or ESDI could run at 16-bit bandwidth along with the RLL or MFM that was not intelligent, also at 16-bit bandwidth. 16-bit referring to SCSI-2, of course. Shouldn't pose a problem, but before you commit, make sure whoever you bought the drive from is willing to help you out with the installation and take the drive back in case you aren't happy. Brian
kdunn@lehi3b15.csee.Lehigh.EDU (Kevin Dunn) (02/23/91)
>In article <7yy0w2w163w@brainiac.raidernet.com> sophist@brainiac.raidernet.com (Phillip McReynolds) writes: >>Is it possible to have both an RLL drive+controller & a SCSI >>drive+controller inhabiting the same machine? If it *is* possible, are >>there any problems which might make such a scheme either troublesome or >>unreliable? I would advise against it. I just spent the last month in that situation. I was running a 65meg RLL drive. (The drive is actually a 42meg Miniscribe 3650 MFM that was formatted RLL by the company I bought the computer from. Cheapwads!) Anyway, I bought an 85meg SCSI (ST 296, I think) and an ST01 controller. About half of the time, both worked. The other half of the time, one or both of the drives wouldn't work AT ALL. It was completely random. A disk crash made me do a low-level format on the 65meg RLL, and from then on it would only Low level format to 42 megs, no matter what I tried. Also, strangely enough, about 45% of the time, the drive would not boot (I tried both the SCSI and RLL as boot drives) from a coldboot: A warm boot, however, worked fine! Weird! I tested each drive alone in the computer, and both worked 100% correctly. Something in the interaction was fouling things up, but, like I said, only randomly. This has been my experience with a SCSI/RLL duo. I hope you have better luck. I too, before I started, was assure by Segate and Miniscribe and various dealers that there would be no problem....
noesis@ucscb.UCSC.EDU (60276000) (03/01/91)
no problem in using both -- i've got a 65M RLL & an 85M SCSI in my '486 and have had NO problems in the last year. the problem with the config is usually the setup: making sure no to have any ROM interference. and watch programs like QEMM as you must EXCLUDE SCSI ram from being mapped -- noesis
poffen@sj.ate.slb.com (Russ Poffenberger) (03/01/91)
In article <1420@lehi3b15.csee.Lehigh.EDU> kdunn@lehi3b15.csee.Lehigh.EDU (Kevin Dunn) writes: >>In article <7yy0w2w163w@brainiac.raidernet.com> sophist@brainiac.raidernet.com (Phillip McReynolds) writes: >>>Is it possible to have both an RLL drive+controller & a SCSI >>>drive+controller inhabiting the same machine? If it *is* possible, are >>>there any problems which might make such a scheme either troublesome or >>>unreliable? > > I would advise against it. I just spent the last month in that situation. > I was running a 65meg RLL drive. (The drive is actually a 42meg Miniscribe >3650 MFM that was formatted RLL by the company I bought the computer from. > Cheapwads!) > Anyway, I bought an 85meg SCSI (ST 296, I think) and an ST01 controller. > About half of the time, both worked. The other half of the time, one or >both of the drives wouldn't work AT ALL. It was completely random. A disk >crash made me do a low-level format on the 65meg RLL, and from then on it >would only Low level format to 42 megs, no matter what I tried. Also, >strangely enough, about 45% of the time, the drive would not boot (I tried >both the SCSI and RLL as boot drives) from a coldboot: A warm boot, however, >worked fine! Weird! > I tested each drive alone in the computer, and both worked 100% correctly. > Something in the interaction was fouling things up, but, like I said, only >randomly. > This has been my experience with a SCSI/RLL duo. I hope you have better >luck. I too, before I started, was assure by Segate and Miniscribe and various >dealers that there would be no problem.... It would probably work better with a REAL SCSI controller. The ST01 isn't a real controller, just a brain-dead adapter. I have successfully run ST506 type drives (MFM,RLL) with my Adaptec AHA1542B controller (REAL controller) with no problems. Note that because of the AT BIOS spec., the ST506 type drive becomes the primary bootable drive. You can't boot off the SCSI, but it is recognized during bootup and is available to DOS. I don't do this anymore because my 327Mb Wren IV is plenty. Russ Poffenberger DOMAIN: poffen@sj.ate.slb.com Schlumberger Technologies UUCP: {uunet,decwrl,amdahl}!sjsca4!poffen 1601 Technology Drive CIS: 72401,276 San Jose, Ca. 95110 (408)437-5254
neese@adaptx1.UUCP (03/03/91)
>/* ---------- "Re: SCSI & RLL: compatible?" ---------- */ >>In article <7yy0w2w163w@brainiac.raidernet.com> sophist@brainiac.raidernet.com (Phillip McReynolds) writes: >>>Is it possible to have both an RLL drive+controller & a SCSI >>>drive+controller inhabiting the same machine? If it *is* possible, are >>>there any problems which might make such a scheme either troublesome or >>>unreliable? > > I would advise against it. I just spent the last month in that situation. > I was running a 65meg RLL drive. (The drive is actually a 42meg Miniscribe >3650 MFM that was formatted RLL by the company I bought the computer from. > Cheapwads!) > Anyway, I bought an 85meg SCSI (ST 296, I think) and an ST01 controller. > About half of the time, both worked. The other half of the time, one or >both of the drives wouldn't work AT ALL. It was completely random. A disk >crash made me do a low-level format on the 65meg RLL, and from then on it >would only Low level format to 42 megs, no matter what I tried. Also, >strangely enough, about 45% of the time, the drive would not boot (I tried >both the SCSI and RLL as boot drives) from a coldboot: A warm boot, however, >worked fine! Weird! > I tested each drive alone in the computer, and both worked 100% correctly. > Something in the interaction was fouling things up, but, like I said, only >randomly. > This has been my experience with a SCSI/RLL duo. I hope you have better >luck. I too, before I started, was assure by Segate and Miniscribe and various >dealers that there would be no problem.... The problem is with the ST0x adapter. The 154x adapter has never had any such problem co-existing with another disk controller (MFM/RLL/ESDI) in the system. The only reason I mention it is the way you presented the problems you experienced. It is not a global SCSI problem. No flame intended, just want to be accurate. Roy Neese Adaptec Senior SCSI Applications Engineer UUCP @ neese@adaptex