Mimsy Were the Borogoves

Mimsy Were the Technocrats: As long as we keep talking about it, it’s technology.

Review of the TRS-80 Model 100/200

Jerry Stratton, May 24, 2016

FullSizeRender for Model 100 from 1916

The TRS-80 Model 100, keyboard and 8-line screen.

I’ve just acquired a TRS-80 Model 100 and I’m taking the giant risk of typing up this review on the Model 100 itself. So far it’s been retaining data when powered off for an hour or so, but how it will hold out when turned off for the 8 or so hours it takes to drive from Michigan to Missouri, and then the 14 or so from Missouri to Texas, I guess I’ll find out.

The manual is unclear on whether the AA batteries, which last for 20 hours of actual use, also assist the NiCAD when the unit is turned off. The NiCAD is probably the original and may or may not be working at all. It doesn’t bode well that unplugging the unit from AC power after installing fresh AA batteries resulted in the unit powering off (though with no data loss). It did not switch seamlessly over to battery power as a modern computer would do.

As a portable computer, this must have been astounding at the time. It has the built-in, simple, word processor that I’m using to type this (it’s more of what we today would call a text editor), an address book, and a scheduler.

The address book and scheduler are literally managed by using the word processor to edit text files; the address book and scheduler apps merely search through the text files, which have completely freeform formatting rules. That is, none.

“Try to keep the record format consistent. For example, you might list the date first, followed by the time, then the location, and finally a comment about the event.”

The Model 100 also has BASIC built in, and BASIC programs can access all of the text files, making this a sort of hard-wired Editorial. That is, you can manipulate your text using BASIC programs that you write or purchase. There is no spell-checker built-in, for example, but I’d be willing to bet that there were spell-checkers available for purchase.

Interestingly, there is very little “save”-ing. Word processor files are automatically saved when exiting the app, and even BASIC files are automatically saved once you give them a name. Trying to save a BASIC program after you’ve named it results in an error: all that is necessary to save is to exit BASIC. Further, file extensions are handled almost automatically: you don’t need to specify extensions when loading or saving word processor, scheduler, or address book files, or even BASIC files. The system appends the correct extension automatically. Only when deleting files do you need to know the extension.

File management is handled through BASIC. There is no rename command, that I can find, but to delete a file you kill it in BASIC.

Almost all configuration is also handled in BASIC. Setting the date and time is done through DATE$ and TIME$, after which the Model 100 mostly keeps them updated. TIME$ seems to lose time occasionally, for reasons I have yet to discern.

The real issue is going to be getting this file off of the Model 100 and onto the web site. There are several ports on the Model 100, but none of them remotely modern. The easiest would be the phone connector, but I don’t have a landline to connect it to, nor a dial-up service to call.

But I do have a cunning plan. First, a simple DB25 to USB RS232 serial adapter should make it possible to connect to the iMac and get the data in a terminal connection, and copy and paste it into a text editor.

Second, it should be simple enough to write a simple Python script to listen in on the serial port and wait for upload or download commands to transfer files back and forth. For extra credit, it could store the files in the iMac’s Dropbox folder, for easy access on an iPad or iPhone.

Tandy Model 200

The Tandy Model 200 has a bigger, pop-up screen.

Further notes on the Model 200

Well, I’m writing this at home: the batteries lasted the three days it took to get from Michigan to Texas. And I have the basic version of the script in step two completed; after remembering that I needed a null modem adapter to connect computer-to-computer, it worked mostly great. I’ll post it this Friday or next Friday in the Hacks section of the blog.

The Model 100’s TELCOM program is extraordinarily simple. There is no real upload and download mechanism. “UPLOAD” simply types to the screen as if you were typing it, and “DOWNLOAD” just captures everything coming into the screen to a file you name. This means that downloaded BASIC files will almost always give an error when you merge them—you have to merge them, because everything is downloaded as text files—and the last line is usually going to be the cursor.

BASIC files themselves are not stored as text, but as partially-compiled code. Because everything is so simple, however, you can tell the server to start accepting an upload, and then exit TELCOM, go into BASIC, and SAVE the BASIC program to the RS232 port as ASCII. TELCOM won’t close the connection when you close TELCOM. Not that closing the connection means much on a hard-wired RS232 port.

I’m typing this on a “Tandy 200” which is a sort-of higher-end Model 100/102. Having exported from the Model 100, it was easy enough to then import to the Model 200. I say “sort of” higher-end because I kind of prefer the Model 100. The Model 100 is smaller and lighter; the main advantage of the 200, at least for my purposes, is the larger screen. It is the same width, but twice as tall. The Model 100 came out in 1983, the Model 200 in 1984. Again, in both cases they must have been pretty impressive for the day. They literally came with everything built-in: screen, modem, keyboard, computer, word processor, address book, calendar, BASIC, and, in the case of the Model 200, a spreadsheet. It’s no wonder journalists loved these things. I would have never gone out without one if I’d had one back in the day. It’s more like a precursor to the iPad than to modern laptops.

I could honestly see using it today as a simple portable word processor. But then, I also use a typewriter when I think the project needs it.

The final step for my script will be transferring it to a $9 CHIP computer, which will turn the CHIP into a cheap, but extremely overpowered, adapter. That is, my plan is to hang a full Linux computer off of the Model 100’s RS232 port to act as an external drive and Internet mediator.

This is important, because the RS232 to USB adapter’s driver, both the one from the vendor and the more current one from the chip-maker, causes my iMac to spontaneously reboot under some still-unknown circumstances. If the same happens using a $9 computer, I’ll be less worried about it.

That, using the current script, will still require an Internet connection. Ultimately I’d like to use the CHIP’s Bluetooth to transfer data directly to the iPad (or iMac) either using some special software or by emulating a keyboard. I don’t know whether USB hosts can act as USB keyboards, but I suspect that if they can, someone has done it for Linux.

Stay tuned.

  1. <- Apple’s bias
  2. Who wants a driverless car? ->