This repository contains the Arduino sketch and the supporting library as well as the schematics for a bathroom scale with auto power-off using a 4-digit 7-segment display and the HX711 and MAX7219 chips.
The code depends on the HX711 library, and on my modification of the LedControl library, which allows an easier way to display characters on the display, though hopefully my pull request will be approved to integrate it into the original one.
For a full explanation of how the code and the circuit works, please visit my blog post.