User Manual

Appendix A
Modem AT Commands
27
Xircom Inc. Mini PCI User’s Guide
&Gn V.22bis Guard Tone Selection
This option is for international use only. It is not used in North America. The AT&Gn
determines which guard tone, if any, to transmit while in answer mode (transmitting in the high
band). The value of n can be 0, 1, or 2. This parameter is set automatically for most countries
that require it.
&G0
No guard tone set.
&G1 Enable RTS/CTS flow control (default).
&G2 1800-Hz guard tone set.
&Jn Auxiliary Relay Option
&J0 Auxiliary relay is never closed.
&J1 Not supported (returns ERROR).
&Kn Local Flow Control Options
The AT&Kn command, where n represents 0-4, determines how the flow control between the
computer and the local modem is handled.
&K0 Disable local flow control.
&K3
Enable RTS/CTS flow control (default).
&K4 Enable XON/XOFF flow control.
&Mn Communications Mode
The AT&Mn command, where n represents 0-4, determines how the flow control between the
computer and the local modem is handled.
&M0
Asynchronous mode (default; supplied for backward compatibility only).
&Pn Pulse Dial Make-to-Break Ratio Selection
The AT&Pn command, where n represents 0, 1, or 2, controls the ratio of the off-hook (make) to
on-hook (break) interval used by the modem when it pulse dials.
&P0
Selects 39:61 make/break ratio at 10 pps (default - U.S.).
&P1 Selects 33:67 make/break ratio at 10 pps (default - Japan).
&P2 Selects 33:67 make/break ratio at 20 pps (option - Japan).
&Qn Asynchronous Communications Mode
&Q0 Asynchronous mode, buffered (same as \N0).
&Q5 Error control mode, buffered (default; same as \N3).
&Q6
Asynchronous mode, buffered (same as \N0).