Maxim Integrated 73M2901CE AT Command - Manual (Page 14)

73M2901CE AT Command User Guide UG_2901CE_027
14 Rev. 2.0
2.15 O[n] – Return to On-Line
The O[n] command is used to go back on-line when the command state was entered by issuing the +++AT
escape sequence or turning DTR from ON to OFF with the appropriated S-Register setting in effect. The
O[n] command applies only to asynchronous operation.
O0
If you have returned to Command state from Data state without breaking a connection, the O0
command will return you on-line (Data state).
O[1-7] Retrain
O1
Similar to O0, but also causes the modem to initiate an equalizer retrain sequence.
O2
Enables the modem to respond to a remote request for retrain.
O3
Disables the modem to respond to a remote request for retrain (default).
O4
Enables speed negotiation.
O5
Disables speed negotiation (default).
O6
Enables rate change to 1200 bps.
O7
Enables rate change to 2400 bps (default).
Note: If commands O0 or O1 are given to the modem while not connected, it will respond with ERROR.
2.16 P – Pulse Dial
Causes the modem to pulse dial until tone dialing is selected or the modem is reset.
2.17 Q[n] – Result Codes On/Off
The Q[n] command tells the modem to either report result codes or to remain quiet. Result codes
acknowledge AT commands and call status events. Also refer to the V[n] and X[n] commands.
Q0 Report Result Codes (default).
Q1 Stay quiet.
2.18 R[n] – Select Data Terminal Ready Option
The R[n] command selects how the Data Terminal Ready ( DTR) signal is used by the modem.
R0 – In Asynchronous mode, the modem ignores
DTR. (Default)
R1 – Modem assumes the Command State when
DTR transitions from ON to OFF.
R2 – Modem goes on-hook (hangs up), disables the Auto Answer mode, and assumes the Command
State when
DTR transitions from ON to OFF. Turning DTR back ON will enable auto-Answer
mode.
R3 – Modem is reset when
DTR transitions from ON to OFF.
R4 – Enable V.23 Turnaround via
DTR (On to Off edge triggered) in Master mode. Turn around is
done via
RTS in all other R command settings.
R5 – Power Down with setting
DTR high (requires hard reset to resume normal operation).