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From: Curtis.Boyle@weyr.FIDONET.ORG (Curtis Boyle)
Newsgroups: comp.os.os9
Subject: Re: CoCo 4
Message-ID: <952.274E0EBE@weyr.FIDONET.ORG>
Date: 24 Nov 90 01:58:17 GMT
Organization: Benden Weyr, Saskatoon Sk. (306)-382-5746
Lines: 11


    Concerning the TC9 being a hundred percent compatible with the Coco 3 for software: It is, at the price of losing the 25% speedup he used to advertise. (Also, some sound routines will be 'funny' due to the  vast differences in sound generating hardware). He has a ROM routine that is hooked in the NMI (Non-Maskable Interrupt) that will intercept any programs attempts to access the PIA's from the Coco 3 (which are not in the TC9). The ROM routine will then diasassemble the code from which it was called t








o figure out what the program was trying to do, and then do it itself using the new hardware. It will then RTI with the proper data set up for the original program, without the original program knowing anything has changed. So it should be able to run anything for the CC3.


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