Talk:Hardware: Hive Interface Board 4
Talking to the AD7124
General SPI:
http://raspberrypi-aa.github.io/session3/spi.html
http://robotics.hobbizine.com/raspiduino.html
SPI Drivers https://community.particle.io/t/porting-spi-code-from-rasberry-pi-to-particle/28159
AD7124:
https://wiki.analog.com/resources/tools-software/uc-drivers/ad7124