User manual

Section 4

AT COMMAND SET

4-3

Repeat Command

When the DPX-213 is in Local Command State (waiting for an attention code), entering

the characters

will cause the DPX-213 to repeat the last command line. The 'A'

character can be in either upper or lower case. If an

is entered directly after turning

on the power, the modem will return an ERROR code.

Command Parameters

Most commands to the DPX-213 have several parameters. These parameters select the

various options for each command. Should the parameter be missing for a particular

command, the modem will substitute the value 0. Should a parameter be outside the

defined range, the modem will return an ERROR code.

Result Codes

After the DPX-213 has executed each command line, it returns a result code to show the

status of the command. The result is in the form of digits (0 to 233) or text. Results

displayed in digit format are often used when the modem is being controlled by a

computer. Results displayed in the text format are suited to terminal control. Result codes

can be disabled by setting Quiet Mode (ATQ1).

Status Registers

Configurations are stored in the Status Registers, called 'S-registers'. The DPX-213 has 24

Status Registers (of which, some are reserved for future expansion or used to maintain

compatibility with the DPX-224). Most commands in the DPX-213 alter values in the

status registers.

4.3 DPX-213 Operating States

There are four distinct operating states for the DPX-213:

1. Idle State

2. Command State

3. Data State

4. On-line command State

A description of each operating states follows.