ESP8266 Community Forum

- Fri Jan 30, 2015 9:05 am #8518 Hi!
it's possible to create a firmware for read a HX711? The HX711 is a precision 24-bit analog-to-digital converter (ADC) designed for weigh scales and industrial control applications to interface directly with a bridge sensor readable with 2 wires. This is for measure a weight of a GPL cylinder and publish result to a MQTT OpenHab topic.

- Mon Mar 09, 2015 8:38 pm #11699 Hello,

I found several links about the HX711.

HX711 with all supporting components on a PCB
http://www.ebay.com/itm/Dual-Channel-Pr ... 418cb69b4b

An arduino project demonstration using the HX711, he seems to be getting 1 gram resolution.
https://www.youtube.com/watch?v=yL9RQgLKw_E

An arduino library for the HX711 on github
https://github.com/bogde/HX711

One of several persons using the HX711 in the arduino forums
http://forum.arduino.cc/index.php?topic=226314.0


It should be possible to use the HX711 on the esp8266, you need to detect digital input signal that are minimum 0.1 microsecond long. The chip itself can do it but I don't know if it can be done with LUA. Search for bitbanging speeds for LUA on the esp8266.

I'm going to eventually make one of these to measure remaining material on a shelf (to other another batch before we run out).

- Wed Jul 01, 2015 4:33 pm #22192 I have a solution for this problem using custom code in NODEMCU firmware. If it is popular enough I can include it in the NODEMCU github.

For now, I am able to do the following
LIB.hx711read, LIB.hx711setgain, LIB.hx711powerdown, LIB.hx711powerup

You can set the Amplifier gain, power down/up and read values using Lua.

- Thu Jul 09, 2015 6:31 am #22834 Wow greath! Please include the libraires into github, i have to test a wifi scale....
Thanks Daniele