Particle Boron & HX711 returning false data

Firmware
1

Hi all,

I have a problem with random numbers coming from a HX711 ADC.
See “capture” image:

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I am generating this output form the following code:

void loop() {
  scale.set_scale(calibration_factor); //Adjust to this calibration factor
  Serial.print("RAW    ");
  Serial.print(scale.read()); 
  Serial.print("    one reading:\t");
  Serial.println(scale.get_units(), 10);
  delay(200);
}

For some reason, the scale.read(); function is extremely volatile, and returns -1 (which is false) nearly 50% of the time.

For (scale.get_units(), 10);, the correct reading is -13kg in this case, but for some reason I get a random 52.47kg (without touching anything). I am have the same issue with other systems in the field, but there the problem seems to be much worse (only giving a correct reading 10% of the time).

Also, here does seem to be other incorrect numbers showing up every now and then, see below:

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To add some more information to help problem solve this issue, I then placed a weight on the scales to change the nominal. With the following result:

Capture2
Capture2661×882 13.9 KB

I have been using a particle Boron to communicate with a HX711 ADC through pins:

HX711ADC scale(A1, A0);

Has anybody got any ideas?

Thanks in advance, Micheál.

2

Perhaps start with a search of these existing threads about issues with this load cell - they may well have solved the problem already ?

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