CMX969 Ver la hoja de datos (PDF) - MX-COM Inc

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componentes Descripción

Fabricante

CMX969

MOTIENT/ARDIS RD-LAP MDC4800 Modem

MX-COM Inc  

COMMUNICATION SEMICONDUCTORS

DATA BULLETIN

CMX969

MOTIENTSM/ARDISSM

RD-LAPTM MDC4800 Modem

Advance Information

Features

• Autonomous Frame Sync

Detection for SFR operation

• Full Packet Data Framing

• Powersave Option

• Low Power, 3.0 to 5.5V operation

Applications

• DataTACTM, MOTIENTSM/ARDISSM,

Dual Mode

(RD-LAPTM and MDC4800 Systems)

• Two-Way Paging Equipment

• Mobile Data Systems

• Wireless Telemetry

• DataTACTM Terminals

RADIO

MODULATOR

RF

DISCRIMINATOR

ANALOG Tx

ANALOG Rx

CMX969

MODEM

DATA

PUMP

DATA AND

CONTROL

BUS

HOST mC

SYSTEM

APPLICATION

PROCESSING

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.

The CMX969 assembles application data received from the host processor, adds forward error correction

(FEC) and error detection (CRC) information and interleaves the result for burst-error protection. After adding

symbol and frame synchronization codewords and channel status symbols, it converts the packet into a

filtered analog baseband signal for modulating the radio transmitter.

In receive mode, the CMX969 performs the reverse function using the analog baseband signals from the

receiver frequency discriminator. After error correction and removal of the packet overhead, the recovered

application data is supplied to the host processor. Any residual uncorrected errors in the data will be flagged.

A readout of the received signal quality is also provided.

An optional Autonomous Frame Sync Detection function is provided for use in MOTIENT/ARDIS systems

employing Single Frequency Re-use operation.

The CMX969 uses signal filtering, data block formats and FEC/CRC algorithms compatible with the MDC and

RD-LAP over-air standards. The device is programmable to operate from a wide choice of Xtal frequencies

and is available in 24-pin PDIP (CMX969P4), 24-pin SSOP (CMX969D5), and 24-pin TSSOP (CMX969E2)

packages.

Radio Data-Link Access Procedure (RD-LAP) is a data communications air interface protocol developed by Motorola Inc.

MOTIENT is a registered service mark of the MOTIENT Company operating the MOTIENT Network. (Formerly known as American Mobile, operating the ARDIS Network).

DataTAC is a registered trademark of Motorola Inc.

¤2001 MX-COM, Inc.

www.mxcom.com Tel: 800 638 5577 336 744 5050 Fax: 336 744 5054

Doc. # 20480211.002

4800 Bethania Station Road, Winston-Salem, NC 27105-1201 USA All trademarks and service marks are held by their respective companies.

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