S Register Conventions; S Register Sample; Other Document Conventions - US Robotics 56K USB Modem User Manual

S Register Conventions

S registers contain parameters used by the modem. The presentation format for an S register is very
similar to the format used for an AT command. Each S register has a standard layout consisting of the
following:
• S register title.
• S register description.
• Parameter description.
The S register title is formatted in large bold letters and begins with a capital S followed by the register
number. The title also includes a descriptive name for the register. The S register description defines the
parameter the S register represents.
S register parameters can have a variety of effects on the functionality of the modem. As a result, the
parameter description can have several forms. The most common form includes the parameter range, the
parameter default, and the units used by the parameter.

S Register Sample

S2—Escape Character (User Defined)
S2 contains the decimal value of the ASCII character used as the escape character. The default value
corresponds to an ASCII +. The escape sequence allows the modem to exit data mode and enter
command mode when online. A value over 127 disables the escape process, i.e., no escape character is
recognized.
• Range: 0—255
• Default: 43 (+)
• Units: ASCII

Other Document Conventions

For the sake of clarity, the following conventions have been adopted and used throughout this document.
Table 2. Other Document Conventions
Item Example
AT Command &C <value>
S Registers S <value>
Parameters <value>
Results Codes OK
Examples —
Conventions Description
AT commands are all capitals followed by parameter values in bold print.
This document does not explicitly use the AT prefix when presenting
commands. However, the AT prefix is used for all examples.
S registers have a capital S followed by the register number.
Parameters or variables always use lowercase lettering enclosed in
brackets, <>.
Result codes are all capitals and italics.
Examples use the Courier font and are shown exactly as they appear
when the commands are entered into a terminal program such as Win-
dows Hyperterminal.
56K USB Modem
User Guide
Command Reference - 10