MT3334HD8 User Guide

#Fn Fallback Modes

n = 0, 1, or 2 Default: #F2

The #F command controls whether the modem will fall back to a lower speed because of an unacceptable error rate. If line conditions deteriorate, the modem has the ability to fall back from its original speed to the next lower speed when operating in V.34, V.32bis, or V.32 mode. If the error rate becomes too great, the modem performs a retrain at the next lower speed. If, after the retrain, the error rate is still too high, the modem performs a retrain at the next lower speed, down to 4800 bps.

If the modem returns online at the original speed after the first retrain, the modem starts a counter and a timer. If three retrains occur within a two-minute period, the modem falls back to 4800 bps.

The fallback and fall-forward speeds for the modem are 33.6K, 31.2K, 28.8K, 26.4K, 24.0K, 21.6K, 19.2K, 16.8K, 14.4K, 12K, 9.6K, and 4.8K bps.

#F0 (or #F) disables fallback when online.

#F1 lets the modem fall back from the starting speed to a low speed of 4800 bps in 2400 bps decrements.

#F2 lets the modem fall back when line conditions deteriorate, but also lets it fall forward in 2400 bps increments if line conditions improve.

&Gn Guard Tones

n = 0, 1, or 2

Default: &G0 (models outside U.K.) or &G2 (U.K. models only)

The &G command is used to control 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.

*Hn Busy-Out After Disconnect

n = 0 or 1 Default: *H0

The *H1 command causes the MT3334HD8 to remain out of service and return a busy signal until configuration from the CommPlete Communication Server’s dedicated management console has finished. If no configuration option is set on the dedicated management console, the MT2834MR remains out of service for ten seconds after disconnect. Register S94 controls the length of the out-of-service, or busy-out, time (see Chapter 4).

*H0 disables busy-out after disconnect.

*H1 enables busy-out after disconnect.

&Pn Set Pulse-Dial Ratios

n = 0 or 1

Default: &P0 (Models outside U.K.) or &P1 (U.K. models only)

The &P command sets the time ratios between the open (break) and closed (make) states of dialing pulses. U.K. models are locked to &P1 (67:33 ratio). See Appendix B for more dial pulse information.

&P0 sets a pulse dial ratio of 60 ms break to 40 ms make.

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CommPlete Communications Server

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Multi-Tech Systems MT3334HD8 #Fn Fallback Modes, Gn Guard Tones, Hn Busy-Out After Disconnect, Pn Set Pulse-Dial Ratios