&T7 INITIATE RDL WITH LOCAL SELF TEST (See Figure 5)

This is a system test, end to end.

The command is valid only if the modems are in the command state with a connection established.

Configure the remote modem with an AT&T4 command so that it will honor a remote digital loopback request.

Enter AT&T7 at the local modem and it will send a digital loopback request to the remote modem. After the RDL acknowledgment signal is received from the remote modem, DSR is turned off (if &S1 is in effect), the on-line state is entered, an OK result code is sent to the DTE, and the test timer is set to the value in S18. While the test is active, the local modem sends a test message to the remote modem and counts the errors in the received (looped back) signal. The modems stay in the command state during the test. When the test is terminated (except by a loss of carrier), the local modem sends the release signal to the remote modem, as in &T6, and reports the three-digit error count to the DTE.

The information text is followed by an OK result code. The test is terminated by loss of carrier, or an H0, &T0, or Z command, and by the S18 timer running out.

RESULT CODES

DESCRIPTION

OK

When command executed is started.

OK

After error count is sent to DTE (&T1,

 

&T3, &T6, &T7 or &T8).

ERROR

If not in on-line command state.

ERROR

If the RDL signal is not acknowledged.

MIU Installation, Operation & Diagnostics Edition: March 30, 1998

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Telenetics MIU2.4 manual T7 Initiate RDL with Local Self Test See Figure, Result Codes Description