The FX949 is a low power CMOS integrated circuit which performs all of the real-time signal and data format-management functions required for full-duplex operation of a CDPD Mobile End Station. The FX949 interfaces directly with the analogue modulation and demodulation circuits of the radio and the host radio/application processor bus. It accepts application data from the processor, constructs a correct Reverse Channel packet containing this data and converts the packet to GMSK analogue signals for transmission. In receive, Forward Channel GMSK signals from the discriminator are demodulated, the packet disassembled, error checked, and the recovered application data passed to the processor. The FX949 is the cost, size, and power efficient alternative to DSP design solutions in high performance OEM products for the Cellular Digital Packet Data wireless services.