Lenovo Watch9 Hacking

More than a year ago I bought a Lenovo Watch9, a very nice and cheap hybrid smartwatch that has served me well until now.

Lenovo Smart Watch9

When the original battery died, I opened it to replace it and I saw that it is powered by the C001S mechanism provided by SMART MOVT company.

It is essentially the same component used by the Fossil hybrid smartwatches and I was actually surprised to find out that the Fossil watches provide much more functionalities (and a better app for smartphone) than mine.

Since I am a very curious person I decided to throw away another 20$ and buy another Lenovo Watch9 to do some experiments.
The ideal goal is to try to flash the Fossil firmware and use it with the Fossil app while enabling all the “hidden” features.

First step is obviously tearing it apart and try to see if there is any kind of serial connection that we can use to see what this Watch is actually running/doing.

With a bit of patience I was able to remove the cover shell without destroying anything inside 😀 and here are the C0001S internals!

I was actually very surprised to see that all the pins are marked, and it’s easy to see the U_rx and U_tx connections.

In the next post I will try to power and connect with the watch hoping that it won’t output chinese 😀