Hacking the EZ430 Chronos Watch on the Mac

Today my TI EZ430 Chronos Watch arrived, and I spent a little bit of time hacking it on my MacBook Air. It turns out that even though the documentation seems to require either a Windows machine or a Linux box, you can communicate with the watch from the Mac by modifying the serial port information in the TCL source. I learnt this from a Google Groups post, and I’ve copied the modified TCL source onto my Github account.

I then tried compiling the OpenChronos source code to build some custom firmware. In order to build the firmware, I had to install the following Mac Ports:

  1. sudo port install msp430-gcc
  2. sudo port install msp430-binutils (actually is probably installed with msp430-gcc)
  3. sudo port install msp430-gdb
  4. sudo port install msp430-libc

I then did a msp430-gcc -print-search-dirs to find out where msp430-gcc include files were. For me they install to the /opt/local/msp430/include/ directory. Following the Readme for OpenChronos, I did a sudo cp gcc/intrinsics.h /opt/local/msp430/include/.

When I tried compiling OpenChronos, the build failed with lots of warnings and quite a few errors. This is because OpenChronos was built using the older msp430-gcc4 project. I fixed the compiler warnings/errors and built an image. I copied the generated build/eZChronos.txt file over to my Chronos-Control-Center directory, and uploaded the image to my watch. Everything seemed to work OK, and the watch is currently running my newly compiled custom firmware!

My modified OpenChronos source is available from GitHub.

6 Replies to “Hacking the EZ430 Chronos Watch on the Mac”

  1. wondering if you have any idea how to run the ez430 chronos control center on mac os? what i really want, is to modify the chronos control center program to call on functions within mathematica using MATHLINK, obviously first step is to get control center working on macbook air. I’m not very good with EE/drivers etc.


    Thanks in advance.

    1. The Chronos Control Center code is written in TCL/TK. You should be able to run it on your Air without too much trouble. You need to make sure that TCL/TK is installed. I’ve got a link to my Github project which has my modified Chronos Control Center which should work fine on an Air.

  2. Howdy! Thank you for posting your research on this watch, I am very grateful for your work. I was a little confused though and was wondering if you could possibly write the step by step process you took to hack the watch? You were clear above but I am a novice in the programming world and it was rather challenging for me.

  3. Hi really nice stuff!!! working great on mountain lion (xdotool doesn’t… and i had to change the comport to usbmodemfa131) Thanks and keep up the good work!!!

  4. Hello brett,

    I am new on MAC, I have being trying to understand basic stuff like how to compile this TCL/TK code… I worked with development of software and firmware for embedded systems but I am strugling to work on MAC.

    I downloaded Xcode, installed macports, fink and msp430-gcc toolchain. I don’t know what should I do next… Can you give me an advice?



  5. Work very well for every options (MBP with ML) except PPT mode. Can’t control mouse like on PC either. Did you change/add something else for this mode? It would be nice to use this feature.


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