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Chapter 4 - Command Mode
&X0 is the default setting, which allows DIP-Switch #11 to control Internal/External Clocking (default
Internal). Internal clocking is when the modem provides transmit clock to the DTE on pin 15 of the
RS-232C/V.24 interface. The &X1 command overrides DIP-Switch #11 and selects External clocking.
If DIP-Switch #11 is UP (External clocking), you can not override Internal clocking. &X2 enables
Slave Clocking. The &X2 Command causes the modem to generate the transmit clock timing (pin 15)
from the receive clock (pin 17) from the DTE (therefore 15 and 17 are the same). In this mode (Slave
Clocking), all timing is controlled by the receive clock.
4.4.5 Command Response (Result Code) Commands

Echo Command Mode Characters E

If the modem is connected to a full-duplex computer, it may be necessary for the modem to be
configured to echo back characters entered while in the Command Mode in order for them to be
displayed. The E command is used to configure the Command Mode echo, with ATE0 disabling the
echo and ATE1 enabling the echo (default).

Result Codes Enable/Disable and No Response Answer Q

The
Q
command enables or disables Result Codes and the No Response Answer mode of operation.
Result Codes may be disabled altogether in certain applications, such as computer-controlled auto
dialing, using the
Q
command.
ATQ1
disables Result Code transmissions.
ATQ0
(or
ATQ
) enables
Result Code transmission.
Regarding No Response Answer, you may want the answer mode handled without responses and
echo turned off, but want the originate mode still intelligent. This is called the No Response Answer
mode.
ATQ2
selects the No Response Answer mode. If you do not select any mode, the factory
default setting (enable Result Codes) is automatically selected.

Result Codes ("Multi-Tech" or "Standard AT") &Q

The modem gives you a choice between the Multi-Tech Result Codes, and Result Codes that more
closely match the standard AT command set responses.
AT&Q1
selects AT responses with no Reliable/Compression modifiers. With this command, the
terse result code for
CONNECT 2400
is
10
.
AT&Q0
selects Multi-Tech responses with Reliable/Compression modifiers. With this command, the
terse result
code for
CONNECT 2400
is
9
.

Result Codes (Verbose/Terse) V

The V command controls whether the modem’s result codes are displayed as word (
“verbose”
) or
single digit (
“terse”
) messages.
For example, if after dialing, no carrier signal is detected, the resulting message can be displayed
either as
NO CARRIER
, or as the digit
3
.
Entering
ATV0
(or
ATV
) causes the modem to display the Result Codes as digits, while
ATV1
displays them as words. If you do not select a method, the factory default setting causes the modem
to display Result Codes as words.