Three serial protocols are supported either fully or in a limited fashion by the ConnexLink product family. RS-232 is a standard serial interface found on many PCs and controllers for point to point communications. RS-485/422 are differential serial interfaces used in both point-to-point and point-to-multipoint applications. RS-485 also includes an addressing scheme for the shared 485 bus. Universal Serial Bus (USB) is a common interface on PCs to provide point to point communication to peripheral devices.