electrokean
commented
8 years ago Don't know if you're still working on this, but essentially your offset is 5219 and your scale is somewhere in the range of -107 to -114. You also shouldn't be connecting the input outside the specified full scale differential input range, typically +/-20mV or +/-40V (5V supply and gain of 128 or 64). Also you can't connect a negative voltage at all, or you'll damage the chip. The input is intended to be +/-40mV offset from AVDD/2. This might be why your readings are changing so little over the 0-40mV range you tested with.
killerkitties
bogde
Hi, wanted to use HX711 24-bit adc standalone to measure voltage range of 2mv - 20mv. Problem is: 1) I cannot interpret the adc output count. 2) What should i do in my code(code below) so that it prints voltages not decimal values. Tried with different values of voltages(shared below), and i am totally confused with the readings. I don't know how to convert these values in voltage. What is the logic behind. Please help! Readings: 0mv --- 5219 1.1mv --- 5095 2.3mv --- 4981 2.5mv --- 4960 2.9mv --- 4918 5mv --- 4693 10.6mv --- 4075 15.1mv --- 3597 22.7mv --- 2700 40.7mv --- 562 5volts --- -8388608 -5volts --- -8388607 Board is arduino leonardo, and a simple voltage divider is used for voltage generation(for testing only). The voltages are measured and calculated from multimeter and hand calculations. I need HX711 do this for me. What is the differential ADC count and voltage relationship...? A bogde/HX711 library is used: https://github.com/bogde/HX711 Code:
include "HX711.h"
define DOUT 3
define CLK 2
HX711 scale(DOUT, CLK); void setup() { Serial.begin(115200); } void loop() { long avg = scale.get_value(60); Serial.print("Digital Code = "); Serial.println(avg); }