CMX7141 Digital PMR Processor

The CMX7141 FI-1.0 implements a half-duplex 4FSK modem and a large proportion of the dPMR Air Interface; Data Link and Call Control layers. In conjunction with a suitable host and a limiter/discriminator based RF transceiver, a compact, low cost, low power digital PMR radio conforming to ETSI's dPMR standard TS 102 490 can be realised. Dual mode, analogue/digital PMR operation can also be achieved with the CMX7141.

The embedded functionality of the CMX7141, managing voice and data systems autonomously including vocoder control, minimises host microcontoller interactions enabling the lowest operating power and therefore the longest battery life for a dPMR radio.

The device utilises CML's proprietary FirmASIC® component technology. On-chip subsystems are configured by a Function Image™: this is a data file that is uploaded during device initialisation and defines the device's function and feature set. The Function Image™ can be loaded automatically from an external EEPROM or host μcontroller over the built-in C-BUS serial interface. The device's functions and features may be enhanced by subsequent Function Image ™ releases, facilitating in-the-field upgrades. This page refers specifically to the features provided by Function Image™ 1.0.

Other features include two auxiliary ADCs with four selectable inputs and four auxiliary DAC interfaces (with an optional RAMDAC on the first DAC output, to facilitate transmitter power ramping).

The device has flexible power saving modes and is available in both LQFP and VQFN packages.