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AT&T 6300 Restoration


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  AT&T 6300 Restoration by Bill Degnan - 07/15/2008 23:09
Cobbled together a system from spare parts, but it's 100% AT&T stock for the 6300. I had trouble with the display for a while, but it revived itself.

The system came to me with generic DOS 4.01.

Decision time If my goal is to return the system to its original state which OS should I install given the following....?

[a] The manual states that DOS 3.1 was shipped with the system.

[b] The original AT&T 3.1 boot disk is missing. I only have the 2nd (supplemental/operating) diskette.

[c] What I do have:
AT&T 3.3
MS DOS 3.1

I decided to go with AT&T 3.3, because manufacturer trumps version IMHO


Two more interesting things.

[1] When the system boots, the system runs Resident Diagnostics Rev. 1.21 ...
at C800:0000

At&T 6300 boot screen when optional ROM present

[2] The ROM reports "fixed disk not present" - yet there is a hard drive and the system boots just fine.


  A few pointers by Jack Harvey - 08/10/2008 08:26
Hello Bill, Yzzerdd here.

You mention that the AT&T PC 6300 runs Resident Diagnostics AT C800:0000. Instead, C800:0000 in this(and most cases) is actually the address of your optional HDD. Every PC 6300 comes with some sort of resident diagnostics at boot-up, ranging from 1.0 to 1.48.

When your 6300 reports not finding a fixed disk present, it does so because you've got a DIP switch set wrong for the hard drive. Try changing SW3 on DIPSW-1 to the opposite position it is in now.

If your goal is to return it to the original state, depending on the systems date, you should use either DOS 3.1, 3.2, or 2.11. Let me know if you need any disks from any of those suites, as I can help you with that. Also, I have the fix to the clock program, which allows you to set the date past 1991. Let me know!

  SW3 #1 to control hard drive by Bill Degnan - 08/10/2008 10:22

Excellent; I will alter the switch.

My earlier post describes how I came to the decision for restoring the OS. I believe because I have original AT&T v. 3.3 disks, although a higher subversion of the shipped OS, trumps a *copy* of AT&T 3.1. Just a personal preference. I fully acknowledge the contrary argument. The whole subject of the best way to restore a computer is of interest and I am always looking for opinions. I plan to get into this topic as a full column issue of this web site, some day.

I have the clock fix, but I did not mention this in my post. Thanks for the offer though.

I have visited your new web site, but for the benefit of anyone who is looking for more AT&T 6300 info, here it is:



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