3Com 56k User's Manual And Reference page 59

&Gn Sets Guard Tone
&G0 No guard tone, U.S. and
Canada
&G1 550 Hz guard tone, some
European countries, requires B0
setting
&G2 1800 Hz guard tone, U.K.,
requires B0 setting
&Hn Sets Transmit Data (TD) flow control,
see also &Rn
&H0 Flow control disabled
&H1 Hardware flow control, Clear to
Send (CTS)
&H2 Software flow control, Xon/Xoff
&H3 Hardware and software flow
control
Technical Reference
&In
&Kn
Sets Receive Data (RD)
software flow control, see also
&Rn
&I0 Software flow control disabled
&I1 Xon/Xoff signals to your
modem and remote system
&I2 Xon/Xoff signals to your
modem only
Enables/disables data
compression
&K0 Data compression disabled
&K1 Auto enable/disable
&K2 Data compression enabled
&K3 MNP5 compression disabled
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