Introduction to Hardware

You can see the hardware by looking at the Patent, Fig 1 (on the right here). This shows a picture of the watch itself, a picture of the LCD display, and a full circuit diagram (over a couple of sub diagrams).

The core processor is an SM510, part of the SM5 Sharp 4 Bit Microcontroller series. Unfortunately, I can't find the databook for this, but I have managed to find the SM511/2 Datasheet which is similar but slightly different.

Unusually the Patent gives a long list of information about the Microcontroller itself - good thing otherwise I'd be stuffed, and between this and the SM511/2 Datasheet I've figured out the minor details.

The SM510 has an LCD Driver built in, so lighting an LCD is just a matter of setting a bit in RAM. The processor takes care of the rest.

The LCD has a slightly unusual pattern for its graphics with the 6 x 6 "split filled circle" graphics. The 3.5 digit 7 Segment Display at the top is for the watch part (or displaying the score).

There is a 32,768Hz Crystal for accurately keeping time, and a Piezo buzzer. This is slightly unusual in that when turned on it provides a 4Khz tone automatically which you then modulate. It is possible to do this quite effectively. If you have a look at the Homebrew Channel F "Pacman" game, for example, despite it only having three tones it actually has a pretty good attempt at producing "Pacman" classic sounds.

Next time a little more about the Sharp Microcontroller which does all the work.