The source
code is released as open source under the
GPL license .
The source code works with the free student edition of the Microchip C30 compiler.
If you want to be able to download new firmware to your own uWatch, then you will need a Microchip programmer that supports the PIC24FJ64GA004 chip using the ICSP interface. Two official programmers that do this are the Microchip ICD2 and the much lower cost PICkit2. The PICkit2 is the recommended programmer.
The PICkit2 is about US$35 and is available from ModTronix, DigiKey, Mouser, Newark, MicroChipDirect, and many other places.
You will need to make up your own 5 wire programming cable. The uWatch connector is included in the kit.
Rev 1.0 of the uWatch source code -
OLD
Rev 1.1 of the uWatch source code -
Rev 1.1 HEX file only -
OLD
Rev 1.2 of the uWatch source code -
Rev 1.2 HEX file only -
OLD
Rev 1.3 of the uWatch source code -
Rev 1.3 HEX file only -
OLD
The LATEST
version of the source code and HEX file is now maintained at the Sourceforge
project page here:
http://sourceforge.net/projects/calcwatch
Thanks to the main firmware developers Hugh, Andrew & Zowki - from version 1.6.0 onwards, there is full support for complex number calculation, and entirely revamped menu system, moon phase display, and several games including CHESS based on the TCSP chess engine.
How to build your own programming/download cable for the PICkit2:
You'll need a 5 or 6 way pin 0.1" pin header connector like THIS ONE. They are available from any electronics hobby shop.
You'll also need some thin insulated stranded cable, and small needle nose pliers to crimp the pins.
If you want you can buy the wire pre-terminated with the correct pin connectors HERE.
The connector on the uWatch requires a fair bit of force to remove, so it recommended that hot-melt glue be used to form a strain relief, as shown in the photo. If you plan to connect and reconnect the uWatch a lot, this is highly recommended.
The two connectors with "hot melt" glue to act as a physical
handling strain relief.
Detail of the final crimp. Note the bottom hook catch locks the
crimp pin into the connector
Wiring table:
| PICkit2 | uWatch | Function |
| 1 | 2 | MCLR |
| 2 | 1 | VCC |
| 3 | 5 | GND |
| 4 | 4 | PGD |
| 5 | 3 | PGC |