User's Guide for ZyXEL Omni 56K USB Modem

Table 6. Physical Layer Capacity

STANDARD

BIT RATE

BAUD RATE

MODULATION

CARRIER FREQUENCY

 

[bps]

[baud]

 

[Hz]

V.90

28000-56000

8000

PCM

0

V.34

2400-33600

multiple

TCM

multiple

V.32bis

14400

2400

128-TCM

1800

V.32bis

12000

2400

64-TCM

1800

V.32bis

9600

2400

 

1800

V.32bis

7200

2400

16-TCM

1800

V.32bis

4800

2400

 

1800

V.32

9600

2400

32-TCM

1800

V.32 uncoded

9600

2400

16-QAM

1800

V.32

4800

2400

4-DPSK

1800

V.23

1200/75

1200/75

FSK

 

V.23

600/75

600/75

FSK

 

V.22bis

2400

600

16-QAM

1200 Call

 

 

 

 

2400 Ans

V.22 (BELL 212)

1200

600

4-DPSK

1200 Call

 

 

 

 

2400 Ans

V.21 (BELL 103)

300

300

FSK

 

Flow Control

This feature refers to stopping and restarting the flow of data into and out of the modem’s transmission and receiving data buffers. Flow control is necessary so that a device does not receive more data than it can handle. The Omni 56K USB provides two kinds of flow control methods.

Hardware CTS/RTS Flow Control

This is a bi-directional flow control where CTS and RTS are simulated RS-232C signals that must be available on your computer. When the modem’s transmission buffer is almost full, the modem drops CTS to signal the DTE that it cannot accept data any more. Turn on the CTS to notify the DTE that it can keep sending data to the modem. On the computer software side, when the receiving buffer of the software is almost full, it drops RTS to signal the modem to stop sending data to the DTE. Turn on the RTS and the modem starts sending data again to the DTE.

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ZyXEL Communications 56K manual Physical Layer Capacity, Hardware CTS/RTS Flow Control

56K specifications

ZyXEL Communications has long been a key player in networking technologies, and their 56K modems stand out as a testament to the company’s commitment to high-performance connectivity. The ZyXEL 56K modem provides users with efficient dial-up internet service, delivering reliable performance for both home and small office environments.

One of the main features of the ZyXEL 56K modem is its data transfer capability, offering speeds of up to 56 Kbps. This speed is accomplished by utilizing the latest advancements in modem technology, enabling users to experience smoother browsing, faster downloads, and efficient email communications. Despite being primarily a legacy technology, the ZyXEL 56K modem continues to be valued in areas where broadband connectivity options are limited or unavailable.

The ZyXEL 56K modem utilizes V.90 and V.92 standards—these protocols define how data is transferred over phone lines. With the V.90 standard, the modem can achieve a maximum download speed of 56 Kbps while upload speeds can reach up to 33.6 Kbps with the V.92 standard. V.92 also introduces enhanced features such as a modem on hold, enabling users to receive voice calls while connected to the internet.

In terms of characteristics, the ZyXEL 56K modem is designed with user experience in mind. Its compact, lightweight design allows easy installation and placement, making it ideal for both home users and professionals. The intuitive user interface, coupled with straightforward installation procedures, ensures that even those with minimal technical knowledge can set up the device without hassle.

Additionally, the ZyXEL 56K modem supports various connectivity options, including serial and USB interfaces, allowing compatibility with a wide range of computers and operating systems. This versatility ensures that users can seamlessly connect to their existing devices, enabling broad usage opportunities.

The modem also features built-in error correction and data compression techniques, which improve data integrity and optimize transmission speeds. Overall, the ZyXEL Communications 56K modem remains a reliable choice for users who require dependable dial-up internet access, showcasing the brand's dedication to fostering connectivity in diverse environments.