AT Commands
F-12 AT Commands
DL Redial the Last Telephone Number Dialed
Redials the last telephone number that the modem dialed.
D/
n Dial a Stored Telephone Number
Where n is a two-digit integer between 01 and 40 that specifies a telephone number
previously stored in the directory with the &Zn= or \Pn command.
Dials one of 40 telephone numbers stored in the directory with the &Zn= or \Pn
command. The telephone number is displayed as it is dialed.
$D Power-Up Diagnostics
Performs power-up diagnostics. Also, when all switches in both banks are up, performs
a reset and power-up diagnostics continuously.
%D
n Disconnect Buffer Delay
Where n is an integer from 0 to 255 representing seconds (Default is 0).
Sets a delay during which the modem attempts to process data in its transmit or receive
buffer before disconnecting. When your software lowers DTR or you type ATH, the
modem attempts for n seconds to empty its transmit buffer before disconnecting. When
carrier drops, the modem attempts for n seconds to empty its receive buffer before
disconnecting. If its buffers are empty or if n=0, the modem disconnects without delay.
If a physical disconnect occurs (for example, the connection drops from too many
retransmissions in reliable mode), the modem can process only the receive buffer. If
the delay expires before the modem empties its buffers or it is in command state at
disconnect, it may loose data.
&D
n DTR Control
&D0
Ignores DTR. DTR is not needed for auto-answer.
&D1
Enters command state on detecting On-to-Off transition of DTR; DTR is not needed
for auto-answer.
&D2
Goes on hook on detecting On-to-Off transition of DTR and prepares the serial port to
accept an AT at any speed. DTR is needed for auto-answer.
&D3
Goes on hook and resets on detecting On-to-Off transition of DTR and prepares the
serial port to accept an AT at any speed. DTR is needed for auto-answer.
The On-to-Off transition of DTR must last as long as the value specified in register S25
(default is 0.05 second). Positive transitions of DTR (Off-to-On) that occur within five
seconds after disconnect are ignored.
