Two HD controllers (Was: Re: Xenix device drivers under Unix)

[Bill Blue]

In article <37102 at conexch.UUCP> root at conexch.UUCP (Larry Dighera) writes:
>Does anyone know if it is possible to use two hard disk controllers under
>Xenix 386 2.3.0 when one is a WD1007-WA2 (ESDI) and the other a WD1006-WA2
>(RLL/MFM)?  Is it necessary to run a specific ESDI release of Xenix or
>install one of SCO's patches to use ESDI drives?

I'm running stock 2.3.1 386 Xenix with two controllers - the first
a DTC 6280 ESDI with two drives, and the second a DTC 7187 RLL with
one drive.  No problems at all as far as Xenix is concerned.  HAd to
change a couple of parms in the kernel, and a hardware patch for the 
interrupt line of the second controller.

I heard long ago that you can't have two controllers of the same type
(I don't know why, but would like to), but just about any other pairing
will work well.

Most people you talk to about combining controller will cite their
experiences with it in DOS -- which is a bit different because you
must maintain ROM compatibility and addressing.  You don't in Xenix,
but do have to pay attention to detail at boot time.  The cards can't
be set in a state that would cause them to interfere with each other
at that time.

--Bill