This is a pocket sized combined add on mouse and 12 key keyboard, from HandyKey Corporation, 141 Mt Sinai Avenue, Mt Sinai, NY 11766, phone (516)474-4405, fax (516)474-3760. They have a neat web site at www.handykey.comd that explains what they are doing, and has some new software drivers.
The mouse works when you thumb the mouse button. You tilt the Twiddler left and right or back and forth to move the mouse pointer. The top three buttons on the keyboard correspond with the mouse buttons. All pretty easy. You can alter the mouse sensitivity to two different settings at any time by pressing either of two keys. This is handy for manipulating single pixels for drawing. And of course, no mouse pad needed, no desk needed, no mouse ball to get fouled up.
The 12 key keyboard uses chording (senses the release of multiple keys), so more than four thousand combinations are potentially available. You can set up key combinations as macros for longer strings of text.
The manual is a mere 27 pages, with lots of white space. Most of the meaty bits relate to setting up macro tables, which are not required when you first start using the Twiddler.
There is also a key assignment card to assist in learning the chords, although many are marked directly on the Twiddler.
The software supplied is intended for MS-Dos, while there is also a driver for MS Windows 3.0 (or 3.1). So far I haven't obtained drivers for OS/2 or Windows 95. There is a nice typing tutor program to assist you in learning the keyboard.
The Twiddler comes with a 9 pin serial connector, and also a keyboard connector. The keyboard connector is used purely to supply power to the Twiddler.
Larry Rudolf (rudolph@lcs.mit.edu) wants to connect a Twiddler to a Psion 3 via the RS232. Reports on failure as at November 1996.