CMX882 Baseband Processor for Leisure Radios with Data D/882/18 April 2009 Full-Feature Audio-Processing, Signalling and GPS Data for Half Duplex FRS, MURS, PMR446 and GMRS Leisure Radios Features Automatic signal type scanning and IRQ on Voice processing facilities, including Tx and Rx detection of valid Rx signals, level or RSSI gain setting and voice/subaudio filtering Tone generator for caller recognition tunes C-BUS serial host interface Programmable power down control RF interface allowing 1 or 2 point modulation Programmable signal detection thresholds Programmable soft limiter Low Power operation with Zero Power mode Enhanced CTCSS and 23/24 bit DCS codecs Uncommitted Aux ADC with switchable input Zero talk down CTCSS decoder performance to monitor signals prevents dropouts Silent operation by removal of unwanted calls All call code and monitor modes for CTCSS Selectable voice companding Audio scrambling Robust Half Duplex FFSK/MSK modem, 1200/2400 bps, gets data through when signal XTCSS channel and data signalling is too degraded for voice for text messaging/paging, location transfer, etc. applications. Robust automatic packet data protocol with: Error correction and detection, Interleaving and data scrambling/privacy coding. 2009 CML Microsystems Plc FRS Baseband Processor CMX882 1.1 Brief Description CMX882, a full-function half-duplex audio and signalling processor IC for FRS and PMR446 type facilities suitable for both complex and simple end-designs. Under the control of the host C, all voiceband requirements are catered for: voiceband and sub-audio filtering, pre/de-emphasis, compression and expansion and audio routing and global level setting with single or two-point modulation in the transmit path. The combination of new and standard signalling functions of this product offer, under software control, increased functionality, versatility and privacy. Standard Extended-Code CTCSS and DCS functions are integrated with the new XTCSS code implementation. XTCSS provides additional and improved squelch- centred privacy codes with the added advantage of silent operation no annoying interference from other sub-audio users. XTCSS fitted radios enjoy more privacy and flexibility of operation. For advanced and enhanced radio operation, the CMX882 provides a 1200/2400 bps free-format and packet data FFSK/MSK modem for text messaging/paging, passing GPS location data (compatible with NMEA 0183) and other data applications. With ultra low power requirements and graduated powersave, this product only requires a smaller, lower- power C than existing FRS/PMR446 solutions. It is available in compact SSOP and TSSOP packages. 2009 CML Microsystems Plc 2 D/882/18