This is the TCL source code from Texas Instruments for the Chronos Control Center used to interface with the TI Chronos EZ430 Watch.
This code was originally posted in Google Groups by Ojas Parekh. It is based on the code that gets distributed with the watch, but has been modified to use the first Mac OS/X serial port.
If the software can't detect the USB dongle, try changing the line
set com "/dev/cu.usbmodem001"