Echo Command Mode Characters E

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.

4.4.5Command Response (Result Code) Commands

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.