Path: utzoo!utgpu!jarvis.csri.toronto.edu!cs.utexas.edu!swrinde!zaphod.mps.ohio-state.edu!sol.ctr.columbia.edu!sdsu!bionet!arisia!sgi!shinobu!odin!odin.corp.sgi.com!portuesi From: portuesi@tweezers.esd.sgi.com (Michael Portuesi) Newsgroups: comp.sys.atari.8bit Subject: Re: Games For The 1200XL Message-ID: Date: 17 Jan 90 13:51:50 GMT References: <1254@ariel.unm.edu> <115200062@uxa.cso.uiuc.edu> <90011.170813SPLITE@MTUS5.BITNET> <5954@umd5.umd.edu> <7872@tekigm2.MEN.TEK.COM> <1990Jan17.010114.8975@uokmax.uucp> Sender: news@odin.SGI.COM Reply-To: portuesi@sgi.com (Michael Portuesi) Organization: Silicon Graphics, Inc., Mtn. View, CA Lines: 37 In-reply-to: norlin@uokmax.uucp's message of 17 Jan 90 01:01:14 GMT >>>>> On 17 Jan 90 01:01:14 GMT, norlin@uokmax.uucp (Norman Lin (NARC)) said: >Has anyone actually found something that will not run on a 1200XL but will run >on any other XL or XE? norman> In ANALOG a few years back, there was one program that did something to the norman> keyboard (I think it made the key repeat rate faster) and I believe that the norman> article mentioned that it worked on the XL's except for the 1200XL. It was norman> a long time ago, so I can't be sure. But if this is the case, it would seem norman> that some timing vectors or such may be marginally altered in the 1200XL. In norman> any event, I seem to remember that the difference, if any, was not great. norman> -- norman> Norman Lin More than likely, this is because the program you mentioned jumped into the OS ROM at an undocumented location, or used an otherwise unsupported feature of the OS ROM. Atari provided a vector table for entry providing documented entry points into all of the documented OS routines. The reason for the vector table was to allow updates to the OS to not break software. Unfortunately, in the 8-bit environment, more often than not programmers threw such guidelines to the wind. After all, they were writing to the hardware registers to get graphics to happen on the screen; why not treat the OS ROM the same way? Software that runs under one version of the OS and not the other is broken, plain and simple. That doesn't alter the fact that such software exists -- which is why the XL's have the Translator disk available. --M -- __ \/ Michael Portuesi Silicon Graphics Computer Systems, Inc. portuesi@SGI.COM Entry Systems Division -- Engineering