KLUDGE@mit-mc.arpa (04/22/83)
From: "James J. Frimmel,Jr." <KLUDGE@mit-mc.arpa> Here are my collected thoughts on the Model 100 (long-winded): About 2 years ago a friend of mine in San Diego asked me for some advice. He had a start-up firm and was planning to manufacture a low-cost office computer system. He gave me considerably more than a penny for my thoughts, so I thought hard, and came up with something very close to the Model 100 in looks. My design would have been more powerful, but I'm sure we'll see some offerings of this same genre with more power soon. My main stipulation was that a personal workstation for the average office worker/executive need not be capable of data processing; to be truly useable as a personal workstation, it must be small enough to fit in a conventional briefcase, and be battery operated. More power can be obtained by networking the portable to a larger computer; no kludgey ribbon cables for CPU expansion. A new CPU kernel only costs around $100, so put a CPU in the expansion box. Tandy's new machine can fill the gap that I perceived in the 'office automation' world. It was so aptly described by a female co-worker: it's "cute". I've had one for 2 weeks or so, and I have found it easy to fall in love with. Now for the meat of this message. Others have run down the raw specifications of the Model 100. I'd like to correct a few things said previously, then go further in depth about the cute li'l computer. Here are the corrections: Now some more details: Tandy has done a marvelous job of hogging Japan's production of some new components, those that are the heart of the Model 100. The HM6117 CMOS 4K RAM is not yet available (that I know of) except in the M100. Two 6117's are piggybacked on one ceramic substrate, a 8K package. The same goes for the 40 character by 8 line display. This display has several 80 pin IC's that control the thing, nicely built (by Sharp). It probably accounts for about $300 of the M100's price. The single ROM package actually has 8 4K ROM chips in one DIP, making a 32K plug-in. The modem is also nicely done. The pulse dialer is a good quality relay, not reed. They used the TI single chip modems (TL062), one each for answer and originate. The keyboard is made by Alps (I think they're based in Switzerland) and has a very nice feel. It is quiet, and can generate 256 codes. Some of the alpha keys are used as a numeric pad when the NUM key is locked down. 16 function keys round things out. The keyboard matrix is decoded in software, in the fashion the model I/III was done (I'm judging from the decoding table in ROM). Cassette I/O has been reliable, using the Panasonic RQ353 miniature cassette recorder. It saves/loads at 1500 BPS, and repeats the sound through the quartz beeper. Beware: a lot of the less expensive recorders would not work. Don't buy anything until you try it. It is compatible with the model 3 & 4 cassette I/O, and the model 4 will come with a cassette utility for getting stuff to/from the model 100. The 'sound generator' is probably just an output bit toggled by the processor, or the cassette port run over to a quartz beeper, since the processor can't continue to do other things during a tone. It has good tone quality and range and the volume (not adjustable) is not offensive. The processor is the CMOS 80C85 from OKI, a japanese semiconductor company. It is pin-for-pin compatible with the Intel 8085; same goes for the 81C55 timer/RAM/parallel I/O chip that is also used. The 8155 seems to be driving printer port. The memory map is a little different than usual. The ROM maps from 0 - 7FFFH while the RAM is installed from FFFFH down. This means that RAM starts at E000H for an 8K machine. The screen is probably memory mapped, but switched in and out, since I can't find it in any unused memory space. On the whole, the software is well done. The basic takes advantage of the unique features of the M100, and has some nice graphics (line, box). The terminal emulation is useable, but limited. Upload and download will not work with half-duplex systems, since XON/XOFF is the only flow control used. That can be remedied by writing your own program, which is not hard. The address book and schedule programs are rather trivial, which leaves a nice gap for me to write software for. Packaging is very positive on this machine. Tandy has turned around on this latest series of releases, giving a good deal of thought to user perspective. The manual is readable, the software, friendly, the feel, comfortable. I think Tandy has a winner here; they will have their market built by folks carrying the M100 around, everyone asking them "what's that?" and trying the thing. This thing will travel, which means lots of exposure. Industry analysts have been playing this machine down, or playing doubting Thomases as to whether there will be a market for the M100. I think they're all missing the boat. In two years there will 2 dozen machines like this one, competing for the fastest growing market: DYNABOOK is almost here!