basic use of this ADC. Sample rate 500Hz. 16bit.
Credit to the AD7705 library: http://www.kerrywong.com/2012/04/18/ad7705ad7706-library-revisited/ and code https://www.instructables.com/id/Arduino-16-bit-500SPS-Dual-Channel-DAQ/
Will attempt to take in serial command to change sample rate and gain on the go. Will also add a display if found useful.