[comp.sys.ibm.pc.hardware] Need help: MFM & RLL drives on same box??!!?

pam1@ra.MsState.Edu (Phillip A. McReynolds) (03/14/91)

My question is simple:  Is there any way in HELL to get a Seagate 238R and a
Seagate 251-1 to co-exist on the same 386 box (DFI 386sx w/AMI bios)?  The
answers I've gotten thus far haven't been hopeful (or helpful).  My options
seem to be these:

1.  Try to RLL the MFM drive.

- Probably won't work since the MFM is a Seagate.  Storage would be unreliable 
in any case.  Besides, this probably isn't the best option for me since my RLL 
controller is 8 bits (an ST11).

2.  Try to MFM the RLL drive.

- A good idea?  Will this work at all?  Would it be reliable?  Presumably the
RLL specs are tighter than the MFM specs so that if 1) I bought an MFM card
(16 bits) I might actually improve performance on the RLL drive although I'd
reduce its storage capacity.

3.  Get a MFM controller and try to make the two controllers work in the same 
box at the same time.

- I'm told that this won't work at all because there'd be memory address
conflicts.  Is this true?

4.  Other solutions?  A special card which might meet my special needs?

Please respond either by email or posting.  I'm desparate for a solution to this
sticky wicket!

Phillip McReynolds
pam1@ra.msstate.edu
sophist@mars.ee.msstate.edu
...!uunet.uu.net!mjbtn!raider!brainiac!sophist

phil@brahms.amd.com (Phil Ngai) (03/15/91)

In article <1149@ra.MsState.Edu> pam1@ra.MsState.Edu (Phillip A. McReynolds) writes:
|My question is simple:  Is there any way in HELL to get a Seagate 238R and a
|Seagate 251-1 to co-exist on the same 386 box (DFI 386sx w/AMI bios)?  The
|answers I've gotten thus far haven't been hopeful (or helpful).  My options

Not helpful? What do you want anyway? The first three options you've
listed seem to be pretty exhaustive. Seems like you don't believe
what people tell you. Why are you asking for more opinions when you
don't believe the ones you have? What would be the point?

|- I'm told that this won't work at all because there'd be memory address
|conflicts.  Is this true?

Yes it's true. No, it's not true. These are the two answers you might
get. How are you going to decide which one you believe?

--
The government is not your mother.
The government doesn't love you.

ntaib@silver.ucs.indiana.edu (Nur Iskandar Taib) (03/16/91)

>2.  Try to MFM the RLL drive.

>- A good idea?  Will this work at all?  Would it be reliable?  Presumably the
>RLL specs are tighter than the MFM specs so that if 1) I bought an MFM card
>(16 bits) I might actually improve performance on the RLL drive although I'd
>reduce its storage capacity.

Ought to work. Supposedly as easy as connecting it to an MFM 
controller and doing a low-level format. A local clone shop
had lots and lots of recalls on RLL drives when they were new,
(Seagate 238 + Adaptec) and ended up doing just this. 

--
-------------------------------------------------------------------------------
Iskandar Taib                        | The only thing worse than Peach ala
Internet: NTAIB@AQUA.UCS.INDIANA.EDU |    Frog is Frog ala Peach
Bitnet:   NTAIB@IUBACS               !
-------------------------------------------------------------------------------

davidsen@sixhub.UUCP (Wm E. Davidsen Jr) (03/18/91)

In article <1149@ra.MsState.Edu> pam1@ra.MsState.Edu (Phillip A. McReynolds) writes:

| 1.  Try to RLL the MFM drive.
| 
| - Probably won't work since the MFM is a Seagate.  Storage would be unreliable 
| in any case.  Besides, this probably isn't the best option for me since my RLL 
| controller is 8 bits (an ST11).

  I ran this system 24 hours a day for over a year with Seagate 251-1
and 4096 drives. I picked up about three bad sectors over that time, and
I think they may have been caused by bad power, since I have seen the
same rate with MFM and ESDI in systems here.

  My reliability was much better with the WD1006VSR2 than several other
RLL controllers I tried. Since this system often has the disk light on
for hours at a time, I doubt that you would beat you system any harder
than I do.

| 2.  Try to MFM the RLL drive.
| 
| - A good idea?  Will this work at all?  Would it be reliable?  Presumably the
| RLL specs are tighter than the MFM specs so that if 1) I bought an MFM card
| (16 bits) I might actually improve performance on the RLL drive although I'd
| reduce its storage capacity.

  Seems to me I did that with a 4199R or whatever the 4096 RLL version
is. I was waiting for a controller and needed some rotating storage
right then. You lose a lot of storage, though.

| 3.  Get a MFM controller and try to make the two controllers work in the same 
| box at the same time.
| 
| - I'm told that this won't work at all because there'd be memory address
| conflicts.  Is this true?

  It's not true under SCO UNIX and Xenix. What's possible under DOS I
wouldn't venture to say. You need to move the BIOS and i/o for DOS, also
the interrupt for UNIX.
-- 
bill davidsen - davidsen@sixhub.uucp (uunet!crdgw1!sixhub!davidsen)
    sysop *IX BBS and Public Access UNIX
    moderator of comp.binaries.ibm.pc and 80386 mailing list
"Stupidity, like virtue, is its own reward" -me