MT3334HD8 User Guide
42 CommPlete Communications Server

&RP Immediate Line Probe

Default: none
This immediate action command initiates a retrain that make s the processor read line probe inform ation
for display using the L9, L10, and L11 commands. It is valid only when online in V.34 mode. Before
issuing the command, you must escape to command mode while remaining online. To combine both
actions, use the following command string: +++AT&RP<CR>.
The modem will not read and store the line probe information from this retrain unless you first issue a
%DP1 command

LnDisplay Line Probe Data

n
= 9–11
Default: none
These immediate action commands cause the modem to display line probe information when it is in V.34
mode. The line probe information must first be read and stored by the modem (see “Read Line Probe
Data”). Data format is controlled by the Format Line Probe Data command, %DF.
The display commands are valid only in online mode. To use them online, you must first escape to
command mode with +++AT<CR>. To return online, enter ATO.
ATL9 displays signal strength information.
ATL10 displays the signal to noise ratio (SNR).
ATL11 displays noise information.
Diagnostic Commands
The MT3334HD8 has two diagnostic commands and four diagnostic modes. The power-on self -test is
activated every time power is applied. The U command selects a loopback test, while the &T command
enables a modem to respond to a loopback test from another modem . See Chapter 5, “Testing the
MT3334HD8,” for a fuller discussion. Refer to the L8 command to see how to list the diagnostic online
status.

&TnRespond to Remote Digital Loopback Signal

n
= 4 or 5
Default: &T5
The &T command enables or disables the modem’s ability to recognize the remote digital loopback (RDL)
test signal. (See Chapter 5 for remote digital loopback test procedures.)
AT&T4 lets the modem respond to an RDL signal, and places it in digital loopback.
AT&T5 causes the modem to ignore the RDL signal.