User Manual

Appendix A
Modem AT Commands
37
Xircom Inc. Mini PCI User’s Guide
S30 Inactivity Timer
• The value specified by this register sets how long the modem will wait (in minutes) before disconnecting
when no data is sent or received. This function is only applicable in buffer mode. It is set by AT\Tn. Values
are 0-255. Default is 0 (disabled).
S34 DTE Throughput Limit
• This register specifies whether the modem should limit throughput when the DTE is operating at higher
speeds (57,600 or 115,200bps)
S34=0
Do not limit throughput (default).
S34=1 Limit throughput to DTE speed.
S35 Data Calling Tone
• This register enables or disables a tone of a certain frequency and cadence as specified in V.25 that
allows remote data/fax/voice discrimination. It is set by AT-Cn. The frequency is 1300 Hz with a cadence
of 0.5 seconds on and 2 seconds off. The default is country-specific. Some countries do not allow data
calling tone to be overridden.
S35=0
Data calling tone disabled (default).
S35=1 Data calling tone enabled.
S36 Negotiation Fallback
• This register specifies the action to be taken in the event of a negotiation failure when error control is
selected.
S36=0,2 Hang up
S36=1,3 Fall back to an asynchronous connection
S36=4,6 Attempt MNP. If MNP fails, hang up.
S36=5,
7
Attempt MNP. If MNP fails, fall back to an asynchronous connection.
S37 Dial Line Rate
S37=0
Maximum modem speed (default).
S37=1 Reserved.
S37=2 1200/75bps.
S37=3 300bps.
S37=4 Reserved.
S37=5 Attempt to connect at 1200bps.
S37=6 Attempt to connect at 2400bps.
S37=7 Attempt to connect at 4800bps.
S37=8 Attempt to connect at 7200bps.
S37=9 Attempt to connect at 9600bps.