Reverse Engineered Ambit Documentation

Communication Protocol

Warning

This is not a specification! This is just an attempt to document what has been discovered about the communication protocol for the Suunto Ambit family of sports watches. As new firmware versions are released and new watches hit the market this information will eventually need to be updated.

The bulk of the Ambit communication protocol was initially reverse engineered by Emil Ljungdahl. Based on his findings, he wrote a C library implementing the protocol and a Wireshark dissector to aid further reverse engineering. Emil announced the availability of his code on SourceForge via the Movescount Linux User Group on 2013-11-04 and later moved his Openambit project to GitHub.

This documentation is based on his code for both the library and the dissector, combined with ongoing analysis of old and new USB packet captures. It structures things slightly differently from the way Emil’s code does. This is done in the hope that the new structure yields a clearer picture.

• Protocol Packets
• Protocol Messages
• Message Payloads