US Robotics 56K Series Manual page 97

Fax Commands (Continued)
+FRS=n Makes the modem wait for a specified length of silence before
sending OK to the screen. The pause is set in10 millisecond intervals. n
is the number of 10
appears.(n=0-255)
Note: This command terminates with OK when either the specified
amount of silence is detected or when the user types anything (which is
ignored).
+FTM=n Transmits data using the modulation specified by n.(n = 3, 24, 48, 72,
96, 97, 98, 121, 122, 145, or 146)
Note: See the "Screen Messages" table at the end of this section for
an explanation of messages that appear in response to this command.
millisecond intervals that pass before OK
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