Howdy y'all,

This is a side project of mine to build a replacement circuit board for the Casio 3208 module, used in the Casio CA-53W and related calculator watches. It is probably not compatible with the 3228 module used in the Databank watches, which have four external buttons instead of two. As a side project, it has no warranty whatsoever and you shouldn't use it for anything.

In the rare case that you find this project to be useful, you owe me a pint of good, hoppy pale ale. All license to use this project is revoked if you try to pass off a pilsner instead.

This project is not yet public, but it will eventually be open source. Please give me time to verify it first.

73 from Pizza Rat City, --Travis

Software Status

Our firmware is freely available in this repository, compiling with the standard MSP430 compiler packages that ship with Debian. It consists of a Clock, a Stopwatch, an RPN Calculator, and a Hex Memory Viewer, all written in C.

Additionally, we've written out own client for the CC430's BootStrap Loader (BSL). You might find it handy for other projects involving that chip, or other MSP430F5 and MSP430F6 chips without USB.

Hardware Status

Our replacement board is based around the CC430F6137, which combines an MSP430 microcontroller with an LCD controller and a sub-GHz radio.

The initial version, the GoodWatch10, lacks a filter chain for the radio and is only useful for verifying the correctness of the non-radio portion of the design. The design is confirmed to be functional, and Travis is wearing one for daily use.

Assembly of the GoodWatch10 is a bit difficult, as components are 0201 wherever possible and the central chip is QFN. We'll be correcting this by switching to 0402 parts for the GoodWatch20, at the same time that we add a Sub-GHz radio and chip antenna.