Interface the HX711 to Pi
Building a Raspberry based electronic scale using the DCT Electronic HX711 board is as easy as Pi!
The DCT board comes with two sets of male headers, straight and right angle, and a metal shield.
You will need a 1x4 female header (2.54mm Pitch Straight Single Row PCB Female Pin Headers) and load cells.
- Order the board for $6.99 on Ebay
This one for $2.19 should work, too. - Download the software from gitHub
git clone https://github.com/ggurov/hx711 - Solder a 1x4 straight female header in P5 on Pi (bottom side of board) and a 1x4 male header on the DCT board
- Solder the load cells to the DCT board.
- Plug the DTC board into the Pi.
- Change the GPIO pins in hx711.c from 30 and 31 to 28 and 30. This way they are all on one side of P5:
#define CLOCK_PIN 30 #define DATA_PIN 28
P5 | Pi | HX711 |
---|---|---|
P5-1 | +5 | Vcc |
P5-3 | GPIO28 | DO/RX |
P5-5 | GPIO30 | CK/TX |
P5-7 | Ground | GND |
Calibration
HX711 Spec Sheet
http://hivetool.org/w/images/d/d2/Hx711_english.pdf