APPENDIX A. AT COMMANDS

 

AT\K2,3

Modem does not clear buffers but sends a break to the

 

 

local DTE

 

 

 

AT\K4,5

Modem sends a break in sequence with any received

 

 

data

 

 

AT\Ln

MNP block transfer control

Default :

0

 

AT\L0

Uses stream mode for MNP link connections

 

 

 

AT\L1

Uses block mode for MNP link connections

 

 

AT\Nn

Operation mode control

Default :

3

 

\N0

Selects normal speed buffered mode (no error correction)

 

 

\N1

Selects direct mode (equivalent to &M0, &Q0)

 

 

\N2

Selects reliable mode. Failure to make reliable connection

 

 

results in the modem hanging-up

 

 

 

\N3

Selects auto-reliable mode

 

 

 

\N4

Selects LAPM error correction mode. Failure to make an

 

 

LAPM error correction connection results in the modem

 

 

hanging-up

 

 

 

\N5

Selects MNP error correction mode. Failure to make an

 

 

MNP error correction connection results in the modem

 

 

hanging-up

 

 

AT\Vn

Connect Message

Default :

0

 

AT\V0

Disable single line connect message.

 

 

 

AT\V1

Enable single line connect message

 

 

AT%Cn *

Compression control

Default :

3

 

%C0

Disables data compression

 

 

 

%C1

Enables MNP5 data compression

 

 

 

%C2

Enables V.42bis data compression

 

 

 

%C3

Enables both MNP5 and V.42bis data compression

 

AT%En

Enable/disable auto-retrain

Default :

2

 

Controls whether the modem will automatically monitor the line quality

 

and request a retrain (%E1) or fall back when line quality is insufficient

 

or fall forward when line quality is sufficient (%E2)

 

 

 

%E0

Disables line quality monitor and auto-retrain

 

 

 

%E1

Enables line quality monitor and auto-retrain

 

 

 

%E2

Enables line quality monitor and fallback/fall forward

 

 

%E3

Enables line quality monitor and auto-retrain, but hang-up

 

 

immediately when EQM reaches hang-up threshold (fast

 

 

hang-up)

 

 

AT%L

Report received signal level

 

 

 

Returns a value identifying the received signal level. The value is

 

implemented as follows:

 

 

 

001 =

Received level of -1dBm

 

 

ACTIVE Professional External Modem User’s Manual

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