From: dionj@sco.COM (Dion)
Subject: Re: SCO ODT 2.0 Compability with Dell 466/M
Organization: The Santa Cruz Operation, Inc.
Date: Wed, 23 Dec 1992 19:40:23 GMT
Keywords: UOD361 66MHz


I have some additional info on booting 66MHz machines...

In article <1992Dec19.000503.17364@sco.com> dionj@sco.COM (Dion)
foolishly wrote:

> [..]
>1. I would not venture to say that ODT 2.0 runs on _any_ 66MHz machine.
>It runs on most of them, and on a few we have seen problems.
>Specifically, our Support department has a new SLS called UOD361
>which addresses 66MHz problems that some customers have had on
>some Dell machines.  If your system fails to boot, contact
>Support@sco.com and request this SLS.
>
[... info about video problems removed .. ]
>
>In article <dlhanson.14.724464652@nap.amoco.com> dlhanson@nap.amoco.com (David L. Hanson ) writes:
>>I am receiving a new Dell 466/M (66Mz 486DX2 chip) sometime next week.
>>I am hoping to use it to run ODT 2.0 which I have sitting in a box beside
>>my desk.  This new Dell has a local bus architecture for video and uses
>>the SG3 chip set.  The sales person said sure it would work with ODT 2.0
>>so I ordered it.  I had second thoughts and talked to Dell tech support;
>>they are not so sure.  From my conversation with them, there are two 
>>issues: 
>
>1. Will SCO ODT 2.0 run on any machine with a 66 Mz 486DX2 chip?
>>2. Secondly, does SCO ODT 2.0 have a driver for the SG3 video chip?
>>Thanks
>>Signature follows:
>"Look unto me, and be ye saved, all the ends of the earth: for I am
>>God, and there is none else."  Isaiah 45:22
>>=========================================================================
>>David L. Hanson       Internet --> dlhanson@nap.amoco.com
>>Amoco Corporation     X.400    --> A=attmail,P=amoco,S=Hanson,G=David,I=L
>>Any opinions expressed are my own!
>

My friends in Support tell me that the UOD361 fix 

a) is not specifically necessary for 66MHz machines, Dell or otherwise. 
   See below for a patch and workaround that works and is safer
   than employing UOD361.

b) Has other fixes that you probably dont need.  Generally, if you
   are not sure you need an SLS, it's safer and cleaner to avoid it.
   
Bottom line: Dont call up and ask for UOD361 because you have a 66MHz
machine.  Follow the below procedure first.  

Thanks to Bela for keeping me honest and providing better info on this.
-Dion

=============================================================================
Here's the IT script:
  
  Adaptec 154x/174x-series host adapter not recognized on fast 486 machine
  
  RELEASE:  SCO UNIX System V/386 Release 3.2 Operating System Version 4.0
            SCO Open Desktop Release 2.0
  
  PROBLEM:  Adaptec 154x/174x-series host adapter is not recognized on fast
            486 machines.
  
  CAUSE:    A loop in the Adaptec 154x driver ("ad") and Adaptec 174x driver
            ("eiad") executes too quickly on fast machines (many 486/66DX2
            and some 486/50DX machines).  The driver asks the adapter whether
            it is present, then checks 131,072 times for a response.  The check
            executes faster on faster machines.  If your machine is particularly
            fast, the loop may complete before the host adapter responds.  When
            that happens, the operating system does not recognize the adapter.
  
  SOLUTION: This problem will be corrected by Maintenance Supplement
            Version 4.2 for SCO UNIX System V/386 Release 3.2 Version 4.0.
            and by the next version of SCO Open Desktop.  Until that
            supplement or version is available, the following two-step
            solution may be used.
  
            (1) During installation, run the machine in a "slow mode".
                Most machines have slowed-down modes which can be enabled
                from a setup program which either resides in the BIOS ROM
                or on a configuration diskette.  For instance, most
                machines can be set to run at a lower clock rate (e.g. 8 or
                25MHz); or the cache can be disabled (both the 486 internal
                cache and any external cache).  Many machines also have a
                "Turbo" button on the front panel.
  
                With the machine slowed down, the host adapter should be
                recognized.  Install your operating system until it is
                ready to be booted from the hard disk.
  
            (2) After successfully installing the system, bring it up in
                System Maintenance (single-user) mode.  Make copies of the
                UNIX kernel and of the drivers to be patched:
  
                 # cd /
                 # cp unix unix.orig
                 # cd /etc/conf/pack.d/ad
                 # cp Driver.o Driver.o.orig
                 # cd /etc/conf/pack.d/eiad
                 # cp Driver.o Driver.o.orig
  
            (3)  To patch the Adaptec 154x series driver:
  
                   Operator input          Computer response
                   --------------          -----------------
                 # cd /etc/conf/pack.d/ad
                 # _fst -w Driver.o -
                 * ahapresent+9?X          ahapresent+0x9: 0x20000
                 * ahapresent+9?W 100000   ahapresent+0x9: 0x20000=    0x100000
                 * aha_sndcmd+9?X          aha_sndcmd+0x9: 0x20000
                 * aha_sndcmd+9?W 100000   aha_sndcmd+0x9: 0x20000=    0x100000
                 * $q
                                  ^^^^^^
                (The above number is a one with five zeros).
  
            (4)  To patch the Adaptec 174x series driver:
  
                   Operator input          Computer response
                   --------------          -----------------
                 # cd /etc/conf/pack.d/eiad
                 # _fst -w Driver.o -
                 * eiad_reset+D?X          eiad_reset+0xd: 0x20000
                 * eiad_reset+D?W 100000   eiad_reset+0xd: 0x20000=    0x100000
                 * eiad_soft_reset+9?X     eiad_soft_reset+0x9: 0x20000
                 * eiad_soft_reset+9?W 100000
                                           eiad_soft_reset+0x9: 0x20000=  0x100000
                 * $q
  
  
            (5)  Relink the kernel and shut down the system:
  
                 # cd /etc/conf/cf.d
                 # ./link_unix -y
                 # sync
                 # reboot
  
                 (It is safe to use reboot(ADM) only because the system is
                 in System Maintenance mode).  The computer reboots.  Now
                 turn off the "slow mode", by changing settings in BIOS
                 setup or a configuration disk, or by turning on the "Turbo"
                 button.  The operating system should boot normally and
                 recognize your Adaptec 154x/174x host adapter.
  
            NOTE: This patch corrects problems with the "ad" and "eiad" drivers
            only.  No other problems are currently known with 66MHz machines
            (as of October 9, 1992).  We are aware of the potential for such
            problems with the "spad" (Adaptec 152x) and "dpt" (DPT PM201x)
            drivers and would appreciate reports of any actual recognition
            problems with these host adapters.
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