[comp.sys.ibm.pc.rt] SCSI on RISC/6000 model 320

lzm@mace.cc.purdue.edu (Chris McCoy) (09/12/90)

We are currently installing our new RISC/6000 model 320 which is
configured with the 320 MB hard disk select, one 150 MB tape backup unit,
one CD-ROM, and 32 MB main memory.  We also have ETHERNET, Async ports,
and the grpahics adapter, thus, we have no more MCA ports available for
expansion.

While installing this beast, I noticed the service manual indicated
that the SCSI channel can support EITHER 4 devices (2 internal, 2 external)
or 7 devices (all external).  Well, the 320 MB disk is on the internal SCSI
and the CD-ROM and TBU are on the external SCSI.  According to the
installation manual and confirmed by our SE, we cannot add another
external SCSI device to this adapter.  Our only option is to add another
internal 320 MB drive to the internal (of course there are options for
swapping what's where, but ...).

Does anyone know the scoop on the SCSI adapter?  We will need to add
another hard disk and would rather purchase a third party drive because
of the cost savings.  As it stands now, our options are extremely
limited.
--

=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
Chris McCoy                         : INTERNET:   mccoy@ecn.purdue.edu
Communication Systems Programmer    : UUCP:       ...!ecn-ee!mccoy
Ag. Computer Network, Purdue Univ.  : VOICE:      (317) 494-8339
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=

adrian@siesoft.co.uk (Adrian Hussey) (09/19/90)

I'm posting this query for a friend. Any replies, preferably by
email, would be greatly appreciated. Thanks for any help you can
give.

cheers

Adrian Hussey

P.S. Apologies if this is an inappropriate newsgroup - if it is,
information telling me where to go would also be helpful! :-)

============QUESTION===============


I have noticed that the boot file IO.SYS (or IBMBIO.COM) contains large
'blank' areas consisting of long strings of zero bytes.

Can anybody out there tell me:

1) what these blank areas are for.

2) do all IO.SYS or IBMBIOS.COM files contain them.

3) is it safe to alter them; ie. store data/code in them.

I am interested in writing a short modification to the boot routine & these
'blank' areas would seem like a convenient place to put it;

===================END======================