Chapter 2 – AT Commands
Multi-Tech Systems, Inc. AT Commands Reference Guide (S000273G) 12
Values: n = 0, 1, or 2
Default: 2
Description: Controls whether or not the modem will automatically monitor the line quality and request
a retrain (%E1) or fall back to a lower speed when line quality is insufficient and fall
forward to a faster speed 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.
Values: None
Default: None
Description: % L Returns a value that indicates the received signal level in dBm. This value is a direct
indication (DAA-dependent) of the receive level at the MDP, not at the telephone line
connector. Examples: 009 = -9 dBm, 043 = -43 dBm, and so on.
Values: None
Default: None
Description: % Q reports line signal quality (DAA-dependent) as a three-digit number. Returns the
higher order byte of the EQM value. Based on the EQM value, retrain or fallback/fall
forward may be initiated if enabled by %E1 or %E2.
Values: n = 0 or 1
Default: 0
Description: Specifies the PCM code type for 56K modulation. Note, however, that the modem
automatically selects the code type if the server sends the proper ID.
%U0 Selects µ-Law coding—us ed i n North America and Japan.
%U1 Selects A-Law coding—used out sid e North America and Japan.
Note: See also the +MS= command.
Note: For use with MT5600BA and MT5600BR only.
Values: n= 0, 1, 2, or 3
Default: 1
Description: \A0 64-character maximum block size.
\A1 128-character maximum block size.
\A2 192-character maximum block size.
\A3 256-character maximum block size.
Values: n = 0–9 in 100 ms units
Default: 3
Description: In non-error-correction mode only, sends a break signal of the specified length to a remote
modem. Works in conjunction with the \K command.