Slightly modified version of the original scale to fit on my espresso machine. I plan to upload the STLs & source code changes shortly.
I used a ESP32 Feather from EzSBC.com (in the USA) which vastly reduces the original Feather's high deepsleep current draw (160mA IIRC) to 10uA.
To enable this feature, I removed the power switch and added an extra button on the front panel. Both buttons activate tactile switches mounted in the body. Holding the left button down > 1sec puts the ESP32 into deepsleep. Battery is at 50% after 2 weeks of daily use with a 1,400mA LiPo. As a note, I originally planned to use an 18650 cell, so it still fits in the case.
I had to add code to handle the new button and handle the deepsleep/wake actions. Finally, the Feather handles reading the battery voltage differently, so more changes to handle that.
Originally I planned to add a 128x64 OLED, remove all the bluetooth/web functionality and display weight & time directly on the scale with auto start etc. Once I started using the graph, I absolutely love it! It allows me to dial in my extraction rate perfectly as can be seen in the attached graph. Figuring out everything else with espresso is still black magic though! (edited)
Slightly modified version of the original scale to fit on my espresso machine. I plan to upload the STLs & source code changes shortly.
I used a ESP32 Feather from EzSBC.com (in the USA) which vastly reduces the original Feather's high deepsleep current draw (160mA IIRC) to 10uA.
To enable this feature, I removed the power switch and added an extra button on the front panel. Both buttons activate tactile switches mounted in the body. Holding the left button down > 1sec puts the ESP32 into deepsleep. Battery is at 50% after 2 weeks of daily use with a 1,400mA LiPo. As a note, I originally planned to use an 18650 cell, so it still fits in the case.
I had to add code to handle the new button and handle the deepsleep/wake actions. Finally, the Feather handles reading the battery voltage differently, so more changes to handle that.
Originally I planned to add a 128x64 OLED, remove all the bluetooth/web functionality and display weight & time directly on the scale with auto start etc. Once I started using the graph, I absolutely love it! It allows me to dial in my extraction rate perfectly as can be seen in the attached graph. Figuring out everything else with espresso is still black magic though! (edited)