Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!ucbvax!ucsd!sdcc6!sdcc19!sdcc15!pa1044
From: pa1044@sdcc15.ucsd.edu (John C. Fowler)
Newsgroups: comp.sys.tandy
Subject: Re: Tandy hardware
Message-ID: <1527@sdcc15.ucsd.edu>
Date: 20 May 89 04:03:13 GMT
References: <25039@ccicpg.UUCP>
Reply-To: pa1044@sdcc15.UCSD.EDU (John C. Fowler)
Distribution: na
Organization: University of California, San Diego
Lines: 52

In article <25039@ccicpg.UUCP> paulm@ccicpg.UUCP (tmp Paul Moreau usenet acct) writes:
>I got the new 1989 Tandy catalog and it had a Model 4D in it.
>I bought a model 4 recently and would like to upgrade it to
>model 4D.  My question is this:
>   Is the only difference the DOUBLE sided drives ?

Yes, that's primarily the only difference.  Additional differences
include a serial board as standard equipment (plus Deskmate, which
almost no one uses anyway).  The Model 4D uses the gate-array type
structure, which differs from the earlier Model 4's.  Unless you
plan to be doing a lot of hardware projects, there isn't much
difference between the non-gate-array and gate-array 4's, from a
software perspective.

>   If I put 2 48 tpi (PC XT types) Double sided drives into
>   my model 4 will the disk controller know how to handle it ?
>   Does TRS-DOS 6.2 or LSI-DOS 6.2/3 know ?

If installed correctly, yes.  The Model 4 disk controller is one of
the best on the market.  You can even run 3.5-inch drives on it
without additional modification (just plug in and go!).  All Model
III and 4 DOS's support double-sided drives, except for TRSDOS 1.3.
However, there are several modifications out there to allow DS
access for that DOS, the newest being called "System 1.5."

>I've only, up to this point, run model 3 software on the thing
>because when I got it, the person had it in storage for years and
>had lost all of the software for it including TRS-DOS.  I have
>a friend that has a model 1 and some of the software he has bought
>has come with model 1 and 3 diskettes.   He gave me the model 3 stuff.

A quick note: this could be a copyright violation.  Despite
providing two diskettes, most software licenses allow only one user
at a time.  Of course, I doubt anybody will sue, but if you're a
purist, you might want to track down some original copies for
yourself.

I see you're familiar with TRSDOS 6.2.1 and LS-DOS 6.3.  Both of
these operating systems should still be available from Radio Shack
and Misosys, respectively.  I recommend the purchase of either if
you wish to use the full capabilities of your Model 4.  Note that if
you get TRSDOS 6.2.1, if you care about whether the date is current
or not, you'll need a patch to go beyond December 1987.  Several of
these are also available.  The best is probably David Goben's
T62DOSXT program, but it's available on a commercial basis only.


-- 
John C. Fowler, pa1044@iugrad2.UCSD.EDU  (I could list others, but why?)
Disclaimer: Could you imagine the ramifications if the Regents of the
	    University of California held MY opinions?
--