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Chapter 4 - Command Mode
Set Pulse Dial Ratios &P
This command sets the time ratios between the open and closed portions of the dialing pulse
frequencies. To set the dialing pulse ratio of 60 mSec to 40 mSec, enter
AT&P0.
To set a ratio of 67
mSec to 33 mSec, enter
AT&P1
. The factory default is
&P0
.
Automatic Pauses in Dialing ,
You can cause the modem to pause during the dialing sequence by entering a comma character
where the pause is desired. This pause lasts two seconds. If a longer pause is desired, more than
one comma may be entered consecutively, with each comma causing a two second pause. You also
have the option of changing the length of the pause caused by the comma, from two seconds to any
other value from 0 up to 255 seconds. This is done by setting S-Register S8 (refer to Chapter 6).
Each comma in a dialing command counts as one of the sixty allowed characters.
Long Space Disconnect Y
When two modems are connected in Normal mode (i.e. without error correction) there is no
"polite"
means of requesting a disconnect. A link disconnect request packet is sent under reliable
connections. As a result some
"garbage"
may be received when a hang-up command is issued. The
Y1 command enables the modem to use the break signal which accomplishes the hang-up as an
instruction to shut off its receiver and disconnect (both modems must have Y1 enabled for this
feature to be effective). Y0 (factory default) disables this function.
Wait for New Dial-Tone W
A
W
inserted in the dialing command causes the modem to wait for another dial tone, and not resume
dialing until another dial tone is detected.
It is not necessary to enter a
W
at the beginning of the dialing command to wait for a modem dial
tone, because the modem will do that first (pause automatically).
In order for this command to work, you must select Wait-For-Dial Tone dialing with the
X2
or
X4
command, so that your modem will be able to detect the dial tone.
Return to Command Mode After Dial Command Execution ;
A semicolon (
;
), entered as the last character of a dialing command causes the modem to return to
the Command mode immediately after executing the command, instead of waiting for a carrier signal
and going on line.
For example, entering
ATDT5551212;
would tone-dial the number, and do nothing afterwards except
go back into Command mode. This can be useful in dialing applications where modem data transfer
is not desired, such as voice communications, or in applications involving the use of touch tones as a
data entry method, such as bank-by-phone.
Reverse the Mode of Operation R
In certain operations you may need to reverse the mode of operation for your modem from originate
to answer or answer to originate so that it would answer the phone and go into answer mode. This
command turns off the reversing function with the
R0
command and turns it on with the
R1
command
with the modem in either command mode. If you want to reverse from the originate mode, use
R
(with
no number) in the dialing string.