User's Manual

0 Automode disabled
1 Automode enabled using V.8 bis/V.8 or V.32 default
Annex A
The default value is 1, which enablesautomode. Note, however, there are modulations for which
there is no automode negotiation, e.g., Bell 212 (<mod>=69).
For <automode> = 0 (automode disabled, i.e., fixed modulation):
a. If <max_rate> is within the rates supported by the selected modulation, the selected rated is that
specified by <max_rate>. For example,
+MS=10, 0, 1200, 4800 selects V.32 bis 4800 bps fixed rate.
b. If <max_rate> is greater than the highest speed supported by the modulation specified by <mod>,
the starting rate is the highest rate supported by the selected modulation. For example,
+MS=10, 0, 2400, 14400 selects V.32 bis 14400, 12000, 9600, 7200, or 4800 bps.
c. To emulate issuance of the N0S37=x command sequence to select fixed mode operation, specify
the <max_rate>and<min_rate> both to be the (same) requested speed, and <mod> to be the
modulation for that speed. For example,
+MS=11, 0, 16800, 16800 selects V.34 16800 bps fixed mode (no comparable S37 command).
+MS=10, 0, 12000, 12000 selects V.32 bis 12000 bps fixed mode (same as N0S37=10).
For <automode> = 1 (automode enabled, i.e., automatically selected speed and modulation):
The modem connects at the highest possible rate in accordance with V.8 bis/V.8, or V.32 bis Annex
A if V.8 bis/V.8 is not supported by the remote modem.
a. If <max_rate> is greater than the highest rate supported by the modulation specified by <mod>,
the modem automodes down from the highest rate of the selected modulation. For example,
+MS=10, 1, 1200, 24000 selects automoding down from V.32 bis 14400 bps.
b. To emulate issuance of the N1S37=x sequence command, specify the modulation and the rate to
start automoding down from using <mod> and <max_rate>, respectively. Set <min_rate> to 300
to allow automoding all the way to V.21 300 bps. For example:
+MS=11, 1, 300, 16800 selects automodestarting at V.34 16800 bps (no comparable S37 command).
+MS=9, 1, 300, 12000 selects automode starting at V.32 bis 12000 bps same as N1S37=10).
3. <min_rate> is an optional number specifies the lowest rate at which the modem may establish a
connection. The value is decimal coded, in units of bps, e.g., 2400 specifies the lowest rate to be
2400 bps. The default is 300 for 300 bps.
4. <max_rate> is an optional number specifies the highest rate at which the modem may establish a
connection. The value is decimal coded, in units of bps, e.g., 14400 specifies the highest rate to
be 14400 bps. The default is 28800 for 28800 bps.
5. <x_law> is an optional number, which specifies the codec type. The options are:
0=µ-Law
1=A-Law
Note that ATZ will reset the <x_law> selection to 0 (µ-law).