The HX711 chip is an ADC designed for weight scales or load cells. It has a 24-bit ADC and a programmable gain amplifier (PGA) with gain up to 128. The interface requires a clock wire and a data wire: the clock is pulsed 25-27 times and 24 bits of data are read from the data line. A number of extra clock pulses are required and tell the chip what gain to use.
This driver is very simple and basically provides a single function to read the ADC. This function is implemented in C using modGPIO in order to perform the read as quickly as possible and meet the timing requirements of the chip. A read takes a couple of milliseconds.
This driver is intended to conform to ECMA-419. An example is provided in the examples directory.