upm  1.7.1
Sensor/Actuator repository for libmraa (v2.0.0)
Public Member Functions

API for the HX711 Analog-to-Digital Converter. More...

Detailed Description

HX711 is a precision 24-bit analog-to-digital converter (ADC) designed for weight scales and industrial control applications to interface directly with a bridge sensor. This module was tested on the Intel(R) Galileo Gen 2 board.

#include "hx711.hpp"
main(int argc, char** argv)
upm::HX711 scale(3, 2);
// 2837: value obtained via calibration
std::cout << scale.getUnits() << std::endl;
return 0;

Public Member Functions

 HX711 (int data, int sck, uint8_t gain=128)
 ~HX711 ()
unsigned long read ()
void setGain (uint8_t gain=128)
unsigned long readAverage (uint8_t times=10)
double getValue (uint8_t times=10)
float getUnits (uint8_t times=1)
void tare (uint8_t times=10)
void setScale (float scale=1.f)

Constructor & Destructor Documentation

HX711 ( int  data,
int  sck,
uint8_t  gain = 128 

HX711 constructor

dataDefines the data pin
sckDefines the clock pin
gainDefines the gain factor Valid values are 128 or 64 for channel A; channel B works with a 32-gain factor only
~HX711 ( )

HX711 destructor

Member Function Documentation

unsigned long read ( )

Waits for the chip to be ready and returns a reading

Raw ADC reading
void setGain ( uint8_t  gain = 128)

Sets the gain factor; takes effect only after a call to read() channel A can be set for a 128 or 64 gain; channel B has a fixed 32-gain factor depending on the parameter; the channel is also set to either A or B

gainDefines the gain factor
unsigned long readAverage ( uint8_t  times = 10)

Returns an average reading

timesDefines how many reading to do
Average reading
double getValue ( uint8_t  times = 10)

Returns (readAverage() - OFFSET)

timesDefines how many readings to do
Current value without the tare weight
float getUnits ( uint8_t  times = 1)

Returns getValue() divided by SCALE

timesDefines how many readings to do
Raw value divided by a value obtained via calibration
void tare ( uint8_t  times = 10)

Sets the OFFSET value for the tare weight

timesDefines how many times to read the tare value
void setScale ( float  scale = 1.f)

Sets the SCALE value This value is used to convert the raw data to human-readable data (measurement units)

scaleValue obtained via calibration

The documentation for this class was generated from the following files: