The XE5686L is not a modem chip but a complete modem including the telephone interface integrated into a compact module. It provides user transferable FCC Part 68 registration and can connect directly to the telephone line through an RJ11 jack. The modem connects to the host through a TTL level serial interface. The XE5686L also includes MNP2-4, MNP10 and V.42 error control and MNP5 and V.42bis data compression to provide an error free connection with the greatest possible data throughput rate.