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LSD20463

SmartHCF™ Mobile Modem

Conexant Systems 

SmartHCF Mobile Modem Designer’s Guide

1.2.3 SmartDAA Features

• Digital PBX line protection

• System side powered DAA operates under poor line current supply conditions

• Wake-on-ring

• Ring detection

• Line polarity reversal detection

• Line current loss detection

• Caller ID (CID) detection

• Pulse dialing

• Line-in-use detection – detects even while on-hook

• Remote hang-up detect – for efficient call termination

• Extension pickup detect

• Call waiting detection

• Meets world-wide DC VI Masks requirements (W models)

1.2.4 Applications

• Laptop, notebook, and handheld computers

• PCI Bus/Mini-PCI embedded system boards

• PCI Bus/Mini-PCI/CardBus plug-in cards

1.3 TECHNICAL OVERVIEW

1.3.1 General Description

Modem operation, including dialing, call progress, telephone line interface, telephone handset interface, voice/speakerphone

interface, and host interface functions are supported and controlled through the V.250, V.251, and V.253-compatible

command set.

The modem hardware connects to the host processor via a PCI/MiniPCI/CardBus bus interface. The OEM adds a crystal

circuit, EEPROM, DIB and LSD power rectifier and filter components, telephone line interface, optional telephone handset

interface, optional voice/speakerphone interface, and other supporting discrete components as required by the modem model

and the application to complete the system.

1.3.2 Host Modem Software

The host modem software performs the following tasks:

1. General modem control, which includes command sets, fax Class 1, TAM, voice/speakerphone, error correction, data

compression, and operating system interface functions.

2. Modem data pump (MDP) control. Binary DSP executable code controlling MDP operation is downloaded as required

during operation. Signal processing, including data and facsimile modulation and demodulation, as well as voice sample

formatting, is performed in the hardware DSP.

3. SmartDAA control, which includes HSD SmartDAA Interface control, LSD configuration and control, telephone line

interface parameter control, and telephone line impedance control.

Configurations of the modem software are provided to support modem models listed in Table 1-1.

1.3.3 Operating Modes

Data/Fax Modes

In V.90/K56flex data modem mode, the modem can receive data from a digital source using a V.90- or K56flex-compatible

central site modem at line speeds up to 56 kbps. Asymmetrical data transmission supports sending data at line speeds up to

V.34 rates. This mode can fallback to full-duplex V.34 mode, and to lower rates, as dictated by line conditions.

In V.34 data modem mode, the modem can operate in 2-wire, full-duplex, asynchronous modes at line rates up to 33.6 kbps.

Data modem modes perform complete handshake and data rate negotiations. Using V.34 modulation to optimize modem

configuration for line conditions, the modem can connect at the highest data rate that the channel can support from 33600

bps down to 2400 bps with automatic fallback. Automode operation in V.34 is provided in accordance with PN3320 and in

V.32 bis in accordance with PN2330. All tone and pattern detection functions required by the applicable ITU or Bell standard

are supported.

In V.32 bis data modem mode, the modem can operate at line speeds up to 14.4 kbps.

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