Host-Based Controller Modem

Data Addendum

AT Command Set

June 15, 1998

 

 

AT Voice Commands Reference (continued)

 

AT+VLS=? Analog Source/Destination Selection and DTMF/Tone Reporting

 

Requests for the modem's DTMF/Tone reporting capabilities are made using this command. For each system configuration in voice mode (i.e., speakerphone and answering machine), the modem reports the capabilities that are enabled for the configuration.

Also, for each configuration, the modem indicates tone-reporting capabilities for each of the three different voice states: voice transmit data, voice receive data, and voice command state (voice idle).

TAD supports each of the following IS-101 analog source/destination configurations:

Label #

Description

0DCE on-hook, local phone connected to Telco.

1DCE off-hook, DCE connected to Telco.

2DCE off-hook, local phone connected to DCE.

3DCE off-hook, local phone connected to Telco, DCE to local phone.

4Speaker connected to DCE, DCE on-hook (playback messages)

5Speaker connected to DCE, DCE off-hook (call screening)

6Microphone connected to DCE, DCE on-hook (record greeting)

7Microphone and speaker connected, DCE off-hook (speakerphone)

AT+VSD=<sds, sdi> Silence Detection (QUIET and SILENCE)

This command sets both the silence detection sensitivity (<sds>) and silence detection interval (<sdi>).

■Larger values of <sds> indicate that the modem is to treat noisier line conditions as silence. <sds> = 128 ; Nominal level of sensitivity; −40 dBm (default) .

<sds> > 128 ; More aggressive ; <sds>=129 is −39 dBm. <sds> < 128 ; Less aggressive; <sds>=127 is −41 dBm.

■The <sdi> specifies the amount of time the modem shall wait before reporting silence to the DTE. It is used for determining :

Presumed hang-up (SILENCE), after which the modem sends <DLE>-s to DTE.

Default is 5 seconds.

AT+VSM=<cml>,<vsr>

Compression Method and Sampling Rate Specifications

This command enables the compression method and sampling specifications where cml = compression method label and vsr = voice sampling rate.

AT+VSM?

Returns the numeric and string labels of the compression method currently in use, and the

 

sampling rate currently in use.

AT+VSM=?

Reports the voice compression methods supported by the DCE, and the voice sampling rates at

 

which they are supported: The default is 129,8000 (16-bit linear, 8.0 kHz )

 

✟ 128, 8-bit linear, (7200, 8000, 11025)

 

✟ 129, 16-bit linear, (7200, 8000, 11025)

 

✟ 130, 8-bit A-law, (8000)

 

✟ 131, 8-bit μ-law, (8000)

 

✟ 132, IMA ADPCM, (8000)

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Lucent Technologies Inc.

Version 1.0

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Lucent Technologies Host-Based Controller Modem AT AT+VSD=sds, sdi Silence Detection Quiet and Silence, At+Vsm?, At+Vsm=?
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Host-Based Controller Modem AT specifications

Lucent Technologies Host-Based Controller Modem AT represents a significant advancement in modem technology, particularly in the realm of telecommunications and data transmission. This modem, renowned for its efficiency and versatility, is characterized by a host-based architecture, which differentiates it from traditional modems that rely heavily on dedicated hardware.

One of the main features of the Lucent Technologies Host-Based Controller Modem AT is its ability to leverage the processing power of the host computer. By utilizing the host's CPU for data encoding and decoding tasks, the modem can reduce the need for specialized hardware components, allowing for a more cost-effective solution. This design not only facilitates lower manufacturing costs but also enhances the overall performance due to the utilization of the host's computational capabilities.

Another notable characteristic is its compliance with the AT command set, which standardizes communications between the modem and the host system. This ensures compatibility with a wide range of software applications and operating systems. The AT command set allows users to control modem functions easily, making it simpler to configure settings, initiate connections, and manage data transfer processes.

The modem also supports various communication protocols, such as V.90 and V.92, enabling high-speed data transmission over traditional telephone lines. With download speeds of up to 56 Kbps and upload speeds of up to 48 Kbps, the Lucent Technologies Host-Based Controller Modem AT is particularly suitable for Internet browsing, email, and other online activities demanding robust data throughput.

Additionally, the modem features built-in error correction and data compression protocols, such as V.42 and V.44, further enhancing the quality and speed of data transmission. These protocols help minimize the impact of line noise and ensure efficient use of bandwidth, leading to improved connection stability and data integrity.

In terms of connectivity, the Lucent Technologies Host-Based Controller Modem AT typically interfaces via a standard serial or USB port, making it compatible with most modern computers. Its compact design and ease of installation make it an appealing choice for both personal and professional use.

Overall, the Lucent Technologies Host-Based Controller Modem AT showcases significant innovation in modem technology, offering users a reliable and efficient solution for high-speed data communications. Its host-based architecture, adherence to the AT command set, and support for advanced communication protocols position it as a vital tool in the ever-evolving landscape of digital connectivity.
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