Rev 5 is finally here!

A project log for Custom Smartwatch

An ESP32 Based Open-Source Smartwatch

Matthew James BellafaireMatthew James Bellafaire 08/19/2020 at 02:030 Comments

The title really says it all here, the boards for Rev 5 arrived earlier today and I dropped everything to start putting them together. Revision 5 brings a huge reduction in overall volume of the watch while maintaining all the intended functionality. For comparison here is the revision 5 board stacked on top of the revision 4.1 board: 

I've talked about the reduction in size in my previous log after the CAD files were finished up. The new size is a noticeable change jumping from the Rev 4. It's also worth noting that the current watch body can be printed entirely without support, this helps with the overall finish since there's no more marks where the supports were removed. 

(the overall reduction in height was only about 3.5mm, Rev 4.1 kind of wraps around the wrist rather than sitting on top of it. The "wings" that hold the strap add a few millimeters to the height making the overall size reduction seem more extreme)

The board assembly went well, I opted to get a stencil this time around to save me some time with the current density of the underside of the board. Overall, the assembly took about 2 hours and the debugging/minor firmware changes only took about another 2. I spent more time desoldering the ESP32 module than anything else (seriously that thing takes forever to heat with hot air station) since it kept ending up with bridges between pins. Other than that, the I2C bus got pulled to ground by some extra solder and the voltage regulator didn't seat properly. As hand assembly of a board goes this watch was a breeze. 

There were some minor code changes that mostly amounted to changing some pin declarations, I'm only mentioning this because it technically means the code from rev 5 and rev 4.1 are incompatible. 

The hardware for this project is now complete. However, I'm not sure whether I'll ever really close this project and consider it finished since I'll continue to add features to the watch as I find a need for them. There's still a lot more to come with this project so stay tuned. Either way see you in the next log!