Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!zaphod.mps.ohio-state.edu!caen!news.cs.indiana.edu!msi.umn.edu!noc.MR.NET!gacvx2.gac.edu!gacvx2.gac.edu!scott Newsgroups: comp.sys.next Subject: Re: The existance of a Software Modem and Fax Machine... Message-ID: From: scott@mcs-server.gac.edu (Scott Hess) Date: 20 Mar 91 17:14:54 References: <1991Mar19.214415.27530@oracle.com> Distribution: na Organization: Gustavus Adolphus College Nntp-Posting-Host: mcs-server.gac.edu In-reply-to: wayer@oracle.uucp's message of 19 Mar 91 21:44:15 GMTLines: 52 In article <1991Mar19.214415.27530@oracle.com> wayer@oracle.uucp (William Ayer) writes: At a demonstration of the NeXT machine two years ago, Jobs suggested that the DSP chip would allow programmers to create a software modem / fax machine (very little hardware would be needed i.e. a cable). Was this suggestion wishful thinking, or could such a beast exist? Well, this is technically possible. Basically, the internals of a modem are a DSP chip plus some glue logic [ :-) ]. The problem is that in a modem the DSP is dedicated, while on the NeXT it isn't quite so dedicated. The amount of work needed to be done outside the DSP is greater on the NeXT than when it's off on that serial port. The DMA support isn't really there, etc, etc. You could upgrade your DSP memory (that would fix most of those types of problems), but in general I think it's a close one as to whether or not you can run a 9600 baud modem off the DSP. On the other hand, 2400 should be fully realizable. I've seen schematics (don't ask me for them - I can't give them out), and I know that people have played with it. One problem is that you need FCC approval to connect this beast to a phone line. With a modem, it's not such a big deal - after all, there's not alot of memory/disk storage in a modem, so it's not really a very good computing machine. Meanwhile, hooking up an interface through the DSP to a NeXT (arguably a fair computing machine), the possibilities are ripe for infamous 'blue boxes'. These would be boxes which could be used to rip off the phone company (free long distance, etc). Not so good. Lastly, I think that a DSP modem is sort of silly. Fact: You're going to be spending >$3500 (after shipping/taxes) on a machine, and realistically most people will be up over $4000. Fact: The box to hang between the DSP and the phone line is probably going to cost $$$ - combined with the appropriate driver software, I'd be surprised if it were under $150 (very surprised at that). Fact: kermit is free. Stuart is nearly so. (Last) Fact: A Hayes compatible MNP 5 modem costs under $200 nowdays for a decent one, lower if you shop. I just don't see the need for a DSP modem. It's too much of a bother, and inflexible to boot. When you can get a cheap modem and the software to drive it most anywhere, it's silly to try for another solution which will not be so cheap and will be hardwired to your machine (you won't need new drivers when NextStep3.0 comes out if you buy a modem). Later, -- scott hess scott@gac.edu Independent NeXT Developer GAC Undergrad "Simply press Control-right-Shift while click-dragging the mouse . . ." "I smoke the nose Lucifer . . . Banana, banana."