Multi-Tech Systems MT5600DSVD User Manual
Page 38
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MultiModemDSVD User Guide
4 AT Commands, S-Registers, and Result Codes
33
Command: &Zy=x Store Telephone Number
Values:
y = 0–3
x = Dialing command
Default:
None
Description:
Stores telephone dial string x in memory location y. Each tele-
phone number dial string can contain up to 34 digits. Dial the
stored number using the command ATDS=y.
Note:
DTR dialing uses the number stored in memory location 0.
Command:
%C
n Data Compression Control
Values:
n = 0, 1, 2, or 3
Default:
3
Description:
Enables or disables data compression negotiation. The modem
can only perform data compression on an error-corrected link.
%C0 Disables data compression.
%C1 Enables MNP 5 data compression negotiation.
%C2 Enables V.42bis data compression negotiation.
%C3 Enables both V.42bis and MNP 5 data compression negotiation.
Note:
This command controls both V.42bis and MNP-5 data
compression, whereas the &E14 and &E15 commands control
only V.42bis data compression. The command in effect is the
one last entered.
Command:
%E
n Line Quality Monitor
Values:
n = 0, 1, or 2
Default:
2
Description:
Controls whether or not the modem will automatically moni-
tor 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
Disable line quality monitor and auto-retrain.
%E1
Enable line quality monitor and auto-retrain.
%E2
Enable line quality monitor and fallback/fall forward.
Command:
%L
Line Signal Level
Values:
None
Default:
None
Description:
%L
Returns a value that indicates the received signal level. The
value returned is a direct indication (DAA-dependent) of the
receive level at the MDP, not at the telephone line connector.
For example, 009 = -9 dBm, 043 = -43 dBm, and so on.
Command:
%Q
Line Signal Quality
Values:
None
Default:
None
Description:
%Q
Reports the 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.