Multi-Tech MultiModem ISIHI-2S, Руководство пользователя

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MultiModemISI Hybrid Series, ISIHI-2S 75
Chapter 4—MODEM AT Commands, S-Registers, Result Codes
Modem
&G
n
Guard Tones
n = 0, 1, or 2
Default: &G0 (models outside U.K.) or &G2 (U.K. models only)
The &G command controls the presence or absence of guard tones from the transmitter
when in answer mode at either 1200 or 2400 bps. Guard tones are used in Europe and
other areas to allow the modem to function in the telephone systems. Guard tones are
not used in the United States. U.K. models are locked at &G2 (1800 Hz guard tone).
&G0 disables ITU-T guard tones.
&G1 enables ITU-T 550 Hz guard tone.
&G2 enables ITU-T 1800 Hz guard tone.
N
n
Modulation Handshake
n = 0 or 1
Default: N1
This command controls whether the local modem performs a negotiated handshake with
the remote modem at connection time, when the communication speed of the two
modems is different.
N0 enables handshaking only at the communication standard specified by S37 and the
ATB command.
N1 always begins the handshake only at the communication standard specified by S37
and the ATB command, but allows fallback to a lower speed as the handshake proceeds.
This is the default.
\T n Inactivity Timer
n = 0
Default: \T0
The inactivity timer specifies the length of time, in minutes, that the modem waits before
disconnecting when no data is sent or received. This timer is specified in register S3. The
\T0 command disables the inactivity timer.
Y n Long Space Disconnect
n = 0
Default: Y0
When two modems are connected in reliable mode, a link disconnect request packet is
sent to request a disconnect. In non-error correction mode, there is no
polite way to
request a disconnect. As a result, some garbage may be received when a hang-up
command is issued.
Y0 disables the modem’s use of the break signal.