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From: jca@pnet01.cts.com (John C. Archambeau)
Newsgroups: comp.unix.sysv386
Subject: Re: MFM/RLL Disk Driver for ISC or ESIX?
Message-ID: <1991Jun13.045604.11819@crash.cts.com>
Date: 13 Jun 91 04:56:04 GMT
Sender: root@crash.cts.com
Organization: People-Net [pnet01], El Cajon CA
Lines: 30

daniel@cis.ucsc.edu (Daniel Edelson) writes:
>In article <1991Jun11.121605.11455@crash.cts.com>, jca@pnet01.cts.com (John C. Archambeau) writes:
>|> mdm@cocktrice.uucp writes:
>|> >Does anyone have a disk driver which would provide support for MFM/RLL drives
>|> >attached to a second controller? 
>|> 
>|> The driver should work as is ....
>
>The problem is that it's virtually impossible to find an MFM/RLL controller
>that can use a secondary IRQ. They all seem to be hardwired for 14 (or is it 15,)
>unlike the ESDI controllers which are often jumper selectable. One way around
>it is to mess with the second controllers edge connector, but this is kind of 
>messy. If anybody knows of an MFM/RLL controller that is jumper selectable to
>IRQ 15, would they care to post that information?

What most of us do is take a WD1003 or WD1006 clone and solder a jumper wire
to the motherboard at IRQ 15.  The disk driver as is does NOT support shared
interrupts in any way, shape or form.  You need to get the controller at
a different IRQ and the secondary port address.

     // JCA

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