Command

bit

dec

hex

Function and description

Ref.

 

 

 

 

times out.

 

 

2

4

4

Enable data calling tone (CNG)

 

 

 

 

 

sending

 

 

3

8

8

Reverse the V.23 channel speed.

&N12

 

 

 

 

Originate mode modem speed

 

 

 

 

 

(Send/Receive) 1200/75;

 

 

 

 

 

Answer mode modem speed

 

 

 

 

 

(Send/Receive) 75/1200

 

 

4

16

10

(Work with &D1 command)

 

 

 

 

 

DTR ON will have the modem

 

 

 

 

 

dial the default number and DTR

 

 

 

 

 

OFF will have the modem hang-

 

 

 

 

 

up and reset to profile 0. When

 

 

 

 

 

the modem is idle (waiting for

 

 

 

 

 

command), it will not dial any

 

 

 

 

 

number when DTR changes from

 

 

 

 

 

ON to OFF

 

S49=

bit

dec

hex

Bit-mapped register

+006

 

3-0

0-15

0-F

Set cellular mode transmit power

 

 

 

 

 

level -9 to -24 dBm. (See also

 

 

 

 

 

S43b2)

 

 

7

0

0

For cellular mode only. Modem

 

 

 

 

 

is installed in office (Default)

 

 

 

128

80

For cellular mode only. Modem

 

 

 

 

 

is connected to a mobile phone

 

S50=

 

dec

hex

Inactively timer, in 10 second

+000

 

 

 

 

units

 

 

 

0-

0-FF

The modem counts when there is

 

 

 

255

 

no data flow in or out of the RS-

 

 

 

 

 

232 serial port. A connection is

 

 

 

 

 

disengaged when the counter

 

Status Registers & Result Codes 121

Page 135
Image 135
ZyXEL Communications U-336SA user manual Status Registers & Result Codes

U-336S, U-336SA specifications

ZyXEL Communications, a leading global provider of networking and cybersecurity solutions, has offered a range of products designed to cater to various connectivity needs. Among these, the U-336SA and U-336S modems stand out for their reliability and performance, particularly in the dial-up category during the heyday of internet access.

The U-336SA and U-336S modems are external devices that revolutionized the way users connected to the internet in the late 1990s and early 2000s. Designed for both home users and small businesses, these modems supported 33.6 Kbps data transfer rates, which, at the time, were considered cutting-edge. This capability allowed for reasonably swift internet browsing, email communication, and file downloads compared to earlier modems.

One notable feature of both the U-336SA and U-336S models is their plug-and-play functionality. This ease of use made them accessible to even the less tech-savvy users, allowing quick and straightforward installation. Users could connect the modems to their PCs or laptops via a standard serial interface, minimizing setup time and complexity.

Additionally, both modems were equipped with error correction and data compression technologies. The V.42 and V.42bis protocols enhanced data integrity during transmission, ensuring that users experienced fewer disruptions and greater reliability in their connecting experience. This was particularly vital for tasks like file transfers and large downloads, where data integrity was paramount.

The modems also featured compatibility with various operating systems, including early versions of Windows, which expanded their appeal to a broader audience. The U-336SA was specifically engineered as a standalone device, while the U-336S could often be used with existing computer systems, showcasing versatility in various deployment scenarios.

In terms of design, both modems were compact and lightweight, allowing for easy portability. This made them suitable for users who required connectivity on the go or in different locations.

Ultimately, the ZyXEL U-336SA and U-336S modems represent a significant technological achievement in the history of internet connectivity. Their introduction set the stage for subsequent advancements in modem technology and played a crucial role in the evolution towards broadband and high-speed internet access that we enjoy today. Their legacy endures in the foundational technologies and protocols that continue to drive modern telecommunications.