The CMX969 is a CMOS integrated circuit that contains all of the baseband signal processing and Medium Access Control (MAC) protocol functions required for a high performance DataTAC dual mode (RD-LAP 19.2kbps and MDC4800 4.8kbps) FSK Wireless Packet Data Modem suitable for use with the MOTIENT/ARDIS network. It interfaces with the modem host processor and the radio modulation/demodulation circuits to deliver reliable two-way transfer of the application data over the wireless link.