[comp.unix.xenix] Resolution of >1024 cylinders question

rosso (Ross Oliver, x537, ionesco) (09/29/89)

In article <6ea.25180a97@ibmpcug.co.uk> ronald@ibmpcug.co.uk (Ronald Khoo)
writes about using SCO XENIX with hard disks having more than 1024 cylinders:
>Yep, Go look at your release notes
>
>	"Some hard disks have more than 1024 cylinders.  At this time,
>	 XENIX supports a maximum of 1024 cylinders."
>
>Sigh.
>
>Oi, Rosso, whatcha gonna do about this ? :-)

Because of the increased demand for support of large disks, we are
changing this policy.  SCO XENIX (and SCO UNIX) will support hard
disks having more than 1024 cylinders provided the following three
conditions are met:

- The disk does not have an MS-DOS partition.

- The disk controller supports the required number of cylinders.

- If the disk is the boot device, the kernel, /xenix, must reside
  completely within the first 1024 cylinders.  The safest way to
  avoid this particular problem is to use the area above cylinder
  1023 as your swap area or second file system.

No software changes are necessary, this is the way SCO XENIX currently
behaves.  The release notes are being rewritten for the next release
to include this information.

Ross Oliver
Technical Support
The Santa Cruz Operation, Inc.

larry@nstar.UUCP (Larry Snyder) (09/29/89)

How about adding 16550A support to the ASY driver that is shipping
with SCO (Xenix)?  Your ASY driver is perfect in every way except it
lacks support for the FIFO buffers with the 16550A chips which in
many cases would could keep a dumb port running in applications that
otherwise would require a smart board.
-- 
Larry Snyder                               uucp:iuvax!ndcheg!ndmath!nstar!larry
The Northern Star Usenet Distribution Site                   Notre Dame, IN USA
 

davidsen@crdos1.crd.ge.COM (Wm E Davidsen Jr) (09/29/89)

In article <6191@viscous.sco.COM>, rosso (Ross Oliver, x537, ionesco) writes:
|  Because of the increased demand for support of large disks, we are
|  changing this policy.  SCO XENIX (and SCO UNIX) will support hard
|  disks having more than 1024 cylinders provided the following three
|  conditions are met:
|  
|  - The disk does not have an MS-DOS partition.

  I thought I'd done this... the DOS partition was the lowest, on tracks
1-49 or so for something the "boot: dos" could handle, and the xenix
partition was above that up to 1224 (I don't have the disk anymore, I'm
best guessing). There were three f/s in the Xenix partition, /, /u, and
/usr/spool).

  Am I misremembering that I did this, or are there cases in which you
can have DOS, too? Remember, you said the >1024 wouldn't work, either.
|  
|  - The disk controller supports the required number of cylinders.
|  
|  - If the disk is the boot device, the kernel, /xenix, must reside
|    completely within the first 1024 cylinders.  The safest way to
|    avoid this particular problem is to use the area above cylinder
|    1023 as your swap area or second file system.

    I definitiely did that.
|  
|  No software changes are necessary, this is the way SCO XENIX currently
|  behaves.  The release notes are being rewritten for the next release
|  to include this information.

  Will this be listed as an enhancement when SCO offers a chance to
upgrade? ;-)
-- 
bill davidsen	(davidsen@crdos1.crd.GE.COM -or- uunet!crdgw1!crdos1!davidsen)
"The world is filled with fools. They blindly follow their so-called
'reason' in the face of the church and common sense. Any fool can see
that the world is flat!" - anon