Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!wuarchive!mit-eddie!uw-beaver!milton!sumax!polari!rwing!eskimo!nanook
From: nanook@eskimo.celestial.com (Robert Dinse)
Newsgroups: comp.sys.tandy
Subject: Re: How do I upgrade a 16B/6000 to 2 meg?
Summary: Upgrade to 2 megs
Message-ID: <598@eskimo.celestial.com>
Date: 10 May 91 23:00:22 GMT
References: <5766@mindlink.bc.ca>
Organization: ESKIMO NORTH (206) 367-3837 SEATTLE WA.
Lines: 14

In article <5766@mindlink.bc.ca>, Bruce_Peltzer@mindlink.bc.ca (Bruce Peltzer) writes:
> I have a TRS-80 Model 16B with a Model 6000 CPU board (8MHz) and a 1 meg ram
> card. I have an additional 1 meg RAM card which I would like to add (if
> possible). I am running Xenix 3.2 (I finally found an upgrade). What I am
> interested in is: would changing the dip switch settings on the RAM card allow
> me to add the memory? The ram cards are also from a 6000. BTW, I don't want to
> use the extra meg as a swap device. I would like to use it as main memory.

     In order to do this you need an MMU upgrade. Stock the MMU can only
address 1 megabyte of memory. Last time I got a price quote from Tandy
it was around $300 if memory serves. I've got a couple of CPU boards with
a custom MMU (that doesn't have a PAL chip - courtesy of design work done
by Monty Schmidt) that works ok with 2-megs but not more than that. I am
speculating that it's a fan-out problem.