Path: utzoo!utgpu!news-server.csri.toronto.edu!mailrus!uwm.edu!zaphod.mps.ohio-state.edu!sdd.hp.com!hplabs!hpfcso!hpfinote!pnl From: pnl@hpfinote.HP.COM (Peter Lim) Newsgroups: comp.sys.ibm.pc Subject: Re: SCSI & MFM ??? HELP...! Message-ID: <19450065@hpfinote.HP.COM> Date: 7 Jun 90 21:19:29 GMT References: <1990Jun5.024609.15000@agate.berkeley.edu> Organization: Hewlett Packard CICD Lines: 97 > I have a dilemma here, and need help... > > Someone, in a previous posting, said that it may be possible to use SCSI > drives with MFM? I was wondering if this is possible... > > I have a 71MB full-height MFM drive installed on a 2FD/2HD controller > card... I have a half-height free, in which I would like to install a > removable media drive (25 ms, using 40MB cartridges), since I find 71 megs > very cramped... The problem lies in that this removable media drive is > a SCSI interface... Now, how would I go about using this, while still > keeping my HD? If there is no inexpensive solution, is there a removable > media (half-height) that I can use with my MFM controller??? I don't mind > access time too much, as long as it's not too slow (< 40ms preferred) > anything between 20-40 MB cartridges are fine... > > thanks for any/all help... > ---------- ************************************************************************ * * * YES and NO ! YES and NO ! YES and NO ! YES and NO ! * * * ************************************************************************ Okay, this is a personal experience HOT from the press. Just got all the mess sought out yesterday midnight. The premise is: About a month ago, I was under the impression that one can have both ESDI and SCSI controllers in an AT system and expect it to work perfectly. I went ahead and bought a SyQuest SQ-555 44 MB removable drive (which sounds like the one you're considering). The drive came with a cheap Seagate ST-01 SCSI host adapter (no floppy controller and looks really cheap). I plugged the combination into my system which has a DTC-6280 ESDI controller in the system. Sure enough it didn't work ! The system would power up and rattle the ESDI drive for a while before declaring, "Missing Operating System". After changing through all the configurations, I gave up. I returned the controller for an upgrade to an ALWAYS IN-2000 controller which comes with floppy controller. Meanwhile, I went over to my friend's place. He has a 386 machine with an Adaptec ESDI and an Adaptec SCSI (AHA-1542A) installed. He has both ESDI and SCSI drives installed and they worked together fine. The ESDI is the primary controller with the SCSI being the secondary. I plugged my SyQuest drive onto his SCSI cable and it works fine with the ESDI drive still running ! I finally received my upgrade SCSI board yesterday. The ALWAYS IN-2000 controller costs me $199 (they gave me a refund of $79 for the ST-01). I of course eagerly plugged the card in after changing the BIOS address to avoid that of my ESDI card. On power on, I got the same old error message I had with the Seagate ST-01 controller, "Missing Operating System" ! I changed the BIOS address further and I/O ports and interrupt but things either didn't change or got worse ! I was all ready to give up and start cursing (thinking of changing ESDI controller ???). Then I decided to try out the floppy drive controller on the new board. I basically made my ESDI board secondary, disabled the floopy controller section, restored the IN-2000 board to its default configuration with floppy controller enabled. Guess what ?! This configuration actually worked ! The SyQuest drive is up and running as drives D: and I: (the ESDI occupied C:, E:, F:, G: and H:) ! ------------------------------------------------------------------------ The moral is: "YES ! There is definitely a chance of getting ESDI (or MFM for that matter) and SCSI to live happily in a system, and ...... BEWARE ! It might not be very straight forward, so ...... MAKE SURE that both your SCSI and ESDI/MFM adapters are extremely configurable to have a better chance." AVOID the Seagate ST-01 ??????? ------------------------------------------------------------------------ The SyQuest drive is delivering about 590 KByte/sec with average seek time of about 29 ms (according to CORETEST). So, I'm happy with the system. Can't say the same few weeks ago ..... Have fun ...... Regards, ## Life is fast enough as it is ........ Peter Lim. ## .... DON'T PUSH IT !! >>>-------, ########################################### : E-mail: plim@hpsgwg.HP.COM Snail-mail: Hewlett Packard Singapore, : Tel: (065)-279-2289 (ICDS, ICS) | Telnet: 520-2289 1150 Depot Road, __\@/__ ... also at: pnl@hpfipnl.HP.COM Singapore 0410. SPLAT !