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Path: utzoo!watmath!clyde!burl!ulysses!mhuxr!mhuxt!houxm!houem!marty1
From: marty1@houem.UUCP (M.BRILLIANT)
Newsgroups: net.micro.trs-80
Subject: What makes the Model 4 work?
Message-ID: <405@houem.UUCP>
Date: Fri, 1-Nov-85 15:53:29 EST
Article-I.D.: houem.405
Posted: Fri Nov  1 15:53:29 1985
Date-Received: Sun, 3-Nov-85 05:00:27 EST
Organization: AT&T Bell Labs, Holmdel NJ
Lines: 21

I am using a Model III and a Model 4, both cassette systems.  As
such, the Model 4 runs only in Model III mode.  The Model III is
being used as an intelligent terminal, but I would like a bigger
display if I could get it cheap.

With disk drives and the right DOS, the Model 4 would do certain
things the Model III can not do, such as display 24 lines of 80
columns each, and address 64K of RAM.  I do not know how this is
done.  I don't think it really depends on having disks; more
likely, it depends on sending the right flags to the right ports.
Can anybody tell me what the trick is?

Alternatively, there is a diskware product called Supermod4, for a
Model 4 running a Model III DOS, that enables the 80x24 screen but
still allows ROM+48KRAM addressing.  Can this product be adapted to
cassette use?

		M. B. Brilliant		houem!marty1
		39 McCampbell Road
		Holmdel, NJ 07733	(201)-946-8147
		AT&T-BL Holmdel, NJ	(201)-949-1858