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I built a scale with my RPI using a standard load cell and HX711, is there a way to stream the data from the load cell to the RPI either from the HX711 or from the load cell itself to the HX711? The purpose would be so I don't have any wires connecting the PI to the scale. I will have 4 scales connected simultaneously so will need separate frequencies I would imagine unless there is a different way. I am looking into a 433MHz RF Transmitter Receiver Pair but not sure if multiple can be used at the same time.

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I would put an ESP32 or similar in between to Pi and HX711. You could build some functions (e.g. tare) into the Arduino so it closer to the weigh scales than the Pi so you can check the device. Note load cells can drift over time if constantly under load so you may need to introduce check and calibration processes.

The HX711 has an Arduino library that will collect the data from the ADC and then the sky is the limit.

I would add a simple MQTT server onto the Pi (using Mosqitto) to receive the data from the ESP and pull the data from the queue via Python on the Pi and archive / process it as needed.

Note the ESP can act as a WiFi AP for the Pi leaving the Ethernet port to be the connection to the LAN.

If you have never used MQTT a good starting place is here

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    Ok thanks a lot for the info, I will look into that. Ideally id like the least amount of components as possible to keep the foot print small. Currently I just have a PI, 4 HX711 connected to 22ga wire. Ideally just removing the wires would be best through some wireless module. – Ryan D Jun 12 '20 at 21:11
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    The HX711 is not smart. It’s designed to use the two wires as raw data so just adding an RF module would not give you timing or error correction even if just use the data output to drive a TX pin. – user115418 Jun 12 '20 at 23:43
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    Thanks, I'm not looking for the HX711 to do anything further, I just want the data its getting from the load cell to stream to the PI. Error checking and timing are done in the py script. – Ryan D Jun 12 '20 at 23:59

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