Path: utzoo!attcan!uunet!bu.edu!snorkelwacker!bloom-beacon!eru!hagbard!sunic!nuug!sigyn.idt.unit.no!solan1.solan.unit.no!thoger
From: thoger@solan1.solan.unit.no (Terje Th|gersen)
Newsgroups: comp.sys.ibm.pc.hardware
Subject: Re: Trouble with BIOS! Help appreciated.
Message-ID: <1990Oct3.162922.23219@idt.unit.no>
Date: 3 Oct 90 16:29:22 GMT
References: <1518@hagbard.dc.luth.se>
Sender: news@idt.unit.no (Usenet news admin)
Reply-To: thoger@solan.unit.no
Organization: Norwegian Institue of Technology
Lines: 24

In article <1518@hagbard.dc.luth.se>, news@hagbard.dc.luth.se (news) writes:
|> Hi,
|> I made a copy of my bios (eprom copy) with the intention of adding some
|> additional hard drives to the drive table.
|> There are only 10 bytes of extra code in the new bios,
|> but it just won't boot the computer!  Why ?
|> Is there some kind of checksum in the code some were ?  or what ?
|> I would like to get the computer running as quick as possible.
|> Any kind of help or hint would be appreciated.
|> Use email.
|> Thanx,
|> 
|> /Ingvar            (ingsa@ext.luth.se)

Hello !

There *is* a checksum on the BIOS, although I don't remember how it's calculated. :-)

On SIMTEL you'll find a package of ROM utilities, and one of them calculates a
correct checksum on your code. The adjustment for the sum is by default done to 
the last byte. I don't even remeber it's name, but I guess a 'grep ROM SIMIBM.IDX'
might do the trick..

  -Terje