Hayes Improved Escape Sequence with Guard Time

The Hayes Improved Escape Sequence with Guard Time (U.S. Patent #4,549,302) is used when the modem is online and you need to enter commands to the modem without disconnecting. The Escape Sequence with Guard Time maintains the connection while you are sending commands to your modem.

A Guard Time must precede and follow the sequence of escape characters so that, should the same characters need to be transmitted in a message, the modem will not accidentally switch to command state. The default Guard Time is 1 second.

The escape sequence character and the Guard Time interval can be changed by assigning different values to registers S2 (for the escape character) and S12 (for the guard time).

To use the Hayes Improved Escape Sequence with Guard Time:

Step 1:  Pause a little longer than the Guard Time.                                                           


Step 2:  Type +++.                                                                                            


Step 3:  Pause again a little longer than the Guard Time.


		  (These pauses help the modem to distinguish the escape 


		  sequence from your message.)                                                                   


Step 4:  Enter any necessary commands to the modem.                                                           


Step 5:  When you are ready to resume your call to a remote 


		  system, type ATO E. The modem returns to the online state.

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