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Lucent Technologies Host-Based Controller Modem AT specifications S38 K56flex Downstream Rate

Models: Host-Based Controller Modem AT

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Host-Based Controller Modem

Data Addendum

AT Command Set

June 15, 1998

 

 

AT Commands Reference S-Registers (continued)

 

S38

K56flex Downstream Rate

 

To force a particular K56flex downstream rate, use S-register S38. S38=0 disables K56flex, and may allow a more reliable V.34 connection. S38=1 default allows the modem to select the downstream rate automatically. Other values of S38 force the downstream rate, with fallback to V.34 if unsuccessful at the configured rate:

S38=0

Disable K56flex

S38=1

Automatic rate selection (default)

S38=2

32 kbit/s

S38=3

34 kbit/s

S38=4

36 kbit/s

S38=5

38 kbit/s

S38=6

40 kbit/s

S38=7

42 kbit/s

S38=8

44 kbit/s

S38=9

46 kbit/s

S38=10

48 kbit/s

S38=11

50 kbit/s

S38=12

52 kbit/s

S38=13

54 kbit/s

S38=14

56 kbit/s

The number of robbed-bit signaling (RBS) frames detected decreases the true DCE rate per the following table:

RBS links

Rate hit (kbit/s)

0

0

1

2

2

4

3

4

4

6

5

8

6

8

For example, if S38=10 and there are 3 RBS links, the K56flex downstream rate will be 48-4=44 kbit/s. The exception to this is for 32 kbit/s and 34 kbit/s, which are the true rates regardless of the number of RBS frames detected.

One special value of S38, S38 = 251, is used for back-to-back (factory) testing of V.34 rates, with DSP code running in external memory. Set S38=251 on both originating and answering modems. (This feature is not valid with ramless solution.)

S42

Auto Rate (default 1, range 0¾1)

This command is used for testing and debugging only.

V.32bis and V.22bis auto rate is disabled. Retrain operation is disabled or enabled in data mode, and fallback is disabled in data mode. In K56flex mode, S42=0 forces connection at the rate specified by S38 (even if the rate cannot be sustained), without fallback to V.34.

0 = auto rate disabled, 1 = enabled.

Range: 0—1

Default: 1

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Lucent Technologies Host-Based Controller Modem AT S38 K56flex Downstream Rate, S42 Auto Rate default 1, range 0 ¾1
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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.