COMSPHERE 3900 Series Modems

Table 4-4

(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.

HDisable

No guard tone.

H550 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.

HLong

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.

HShort

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.

4-32

November 1996

3910-A2-GN32-30

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Paradyne 3910 operation manual V22b Guard Tone Disable Nxt Disable 550Hz 1800Hz