COMSPHERE 3900 Series Modems
5-32
September 1998
3910-A2-GN32-40
Table 5-4
(3 of 3)
Dial Line Configuration Options
V22b Guard Tone: Disable
Nxt Disable 550Hz 1800Hz
This configuration option only appears when Dial Line Rate is configured for V.22bis or V.22 data
rate, or when V.32bis Automode is configured for Enable.
V.22bis Guard Tone. Determines whether the V.22bis guard tone is disabled, set to 550 Hz, or set to
1800 Hz.
H
Disable
No guard tone.
H
550 Hz or 1800 Hz
When the modem is in Answer mode, it transmits the guard tone at this frequency.
NOTE: The V.22bis Guard Tone cannot be disabled in some countries.
The AT command for Disable is &G0.
The AT command for 550 Hz is &G1.
The AT command for 1800 Hz is &G2.
V32bis Train: Long
End Long Short
This configuration option only appears when Dial Line Rate is configured for V.32 terbo, V.32bis, or
V.32 data rate.
V.32bis Train. Controls V.32 terbo/V.32bis/V.32 train time. Determines whether minimum or maximum time
durations are used during the V.32 terbo/V.32bis/V.32 handshaking sequence for both dial and 4-wire/2-wire
leased-line applications.
H
Long
Selects long train. Use this setting whenever far-end frequency offset (phase roll) may be
encountered. This is usually only required when transmitting over satellite links.
H
Short
Allows the modem to train-up faster when using V.32 terbo/V.32bis/V.32 modulation.
The AT command is S-Register S43=n, where n is 0 for Long and 1 for Short.
