Path: utzoo!utgpu!water!watmath!clyde!att!rutgers!mailrus!cornell!uw-beaver!tikal!toybox!msa
From: msa@toybox.UUCP (Mark Anacker)
Newsgroups: comp.sys.tandy
Subject: Re: Old peripherals
Summary: sleazy advertising practices
Keywords: coco 100 102 200 disk video controller
Message-ID: <177@toybox.UUCP>
Date: 27 Sep 88 21:45:18 GMT
References: <284@pte.UUCP>
Organization: USWest NSI, Bellevue, WA
Lines: 55

In article <284@pte.UUCP>, car@pte.UUCP (Chris Rende) writes:
> At the moment, Radio Shack has low prices on the following old peripherals:
> 
> 26-3142: Programmable Controller (Plug 'N Power) for the Color Computer
> 26-3806: Disk/Video interface for the Model's 100/102/200

[activating flame thrower...]

DON'T COUNT ON GETTING ONE!  The so-called "Sale" appears to be a way to
get people into the stores.  I tried 14 Radio Shack stores in this area,
both on the phone and in person.  Most of them just stared blankly when
I asked about the DVI.  Once they got the idea that I wanted a Model
100 disk drive, they were more than happy to show me the $250+ model.
NOT ONE OF THESE STORES HAD CARRIED THE DVI IN TWO YEARS!!!  Finally,
I got a manager at a RS Computer Center to admit that the only
qualification for including an item in the flyer was that 100 units had
to show in the inventory SOMEWHERE IN THE WORLD.  They don't have to be
available for sale anywhere, or even at all!  But he was sure doing a
great job moving the portable disk drives.

Personally, I consider this a form of bait-and-switch.  I don't mind
having to look around for an item, but I think if it is nationally
advertised, then it should be reasonably available.  The DVI is not.

[flame off]

> The Disk/Video interface would (might) give my 64x16 Model I 80x25 video! By
> searching my old Radio Shack catalogs I managed to find a picture of the Disk
> /Video unit connected to a Model 100 via a ribbon cable. More than likely 
> this is the same type of connection use between the Model I CPU and its
> Expansion Interface - i.e., a memory mapped bus of sorts. If this is the case
> then interfacing to this device might not be too bad. I was not able to get
> a look at the manual for this one to see if the connector pinout spec's are
> in it.

I'd be very much surprised if they are the same.  If you'd like, I can
e-mail the Model 100/102 pinouts.

> If anyone has any insite that they can give me on either of these devices
> I'd appreciate it. (What CPU is in a Model 100/102/200?)

The Model 100 and 102 use an Intel 80C85.  This is almost identical
to the 8080, with a few (2, actually) additional instructions and CMOS.

> -- 
> Christopher A. Rende         Multics,DTSS,Shortwave,Scanners,StarTrek
> uunet!edsews!rphroy!pte!car  TRS-80 Model I: Buy Sell Trade
> Motorola VME 1131 M68020


-- 
Mark Anacker, US West Network Systems Inc., Bellevue, WA
{...uw-beaver!tikal,...!thebes}!toybox!msa -or- msa@toybox
    "Their mission read, To Boldly Go,
     But how ill-bred, To phrase it so." - Phil Garland