AT&D Controlling Data Terminal Ready, AT&D0, AT&D1 | Telenetics 56

ATCommands

AT&D Controlling Data Terminal Ready

The DTR signal is used to indicate to the modem whether your computer is ready to communicate.

☞The &D command will only take effect when the DTR option switch is in the UP position and %S0 is selected. (See the Dumb Mode Section for details.)

Options

AT&D0	The modem ignores the DTR signal and acts as if it is asserted (the modem
	assumes the computer is ready to communicate).
AT&D1	The modem will return to on line command state if DTR is lowered during a
	connection.
AT&D2 ■	The modem will hang up, return to local command state and disable auto-
	answer whilst DTR is low (is not asserted).
	To enable auto-answer, the DTR signal must be asserted.
	The computer must assert DTR before dialling or answering may commence.
AT&D3	If DTR is lowered, the modem will hang up, return to local command state
	and initialise itself with the values stored in the &Y profile.
AT&D4	The modem will hang up, return to local command state and go off-hook. It
	will remain off-hook whilst DTR is low.

☞S Register 25 determines how long DTR must be low before the modem recognises it as such.

☞S Register 57 determines how long DTR must be high before the modem recognises it as such.

Range

0-4

See Also

S 25, S 57 DTR Detection Times

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Telenetics 56 manual AT&D Controlling Data Terminal Ready, AT&D0, AT&D1, AT&D3, AT&D4

Contents

Global Carrier 56 Modem User’s Guide Page Contact Information Technical SupportMailing List Contents 106 203 248 RS-232 Signals Error CorrectionDumb Mode AT Commands Additional Items You Need Unpacking Your Hardware DTE RS232 Hardware OverviewBack View Front View Finding a Suitable Location Installation Summary Connecting the Cables Set Connector Power InputTelco/Dial Line Telephone Driver Installation WindowsWindows ME Modem LED Display Front Panel Mode LEDs Line Modulation OneThree Four AT Commands Multiple CommandsEscape Sequence Help Command Repeat Command Dialling Response Codes Dial Modifiers Hanging Up Stored Number DiallingAnswering Calls ATCommands Terminal Speeds Selecting Speeds Setting Terminal Speeds 90 & V.34 Typical SettingsLine Speeds Example 2 Dialling other modems at 14,400 bps or V.32bis 32bis Modem Typical SettingsExample 3 Dialling information services at 1200 bps or Example 2 Dialling other modems at 19,200 bps V.34 or V.FC Example 3 Answering incoming calls Transparent XON/XOFF Flow Control Flow ControlRTS/CTS Flow Control XON/XOFF Flow Control AT\T5 Inactivity TimerCommand Timer Failsafe Flow Control Viewing the Current Configuration Configuring the Modem Error Correction Protocols Error Correction Reliable Mode Auto-Reliable ModeData Compression Improving Performance with MNP Cellular Modem Users Speed Changes ATCommands Security Menu Entering a Security Password Adding and Changing Users Access Record Removing UsersListing Existing Users Quitting the Menu Enabling Modem Security Callback Security Downloading the Security File Integrating Caller ID into the Security Database Encryption DES Multikey SuperSecure Advanced Security Mode Entering a Key for Each User Ringing Accessing a System Using SuperSecure Enabling Rotating Secondary Keys Password Expiry Option Entering a Password in the Remote Modem’s Database Entering a New Password in the Local Modem’s DatabaseMinimum Password Length Security Database Lock Option Outdial Disable Option General Notes on Data Security Dial Stored Phone Numbers Only Option Synchronous Operation Synchronous Modes Synchronous Mode Selecting Synchronous ModeDialling Answering Calls Hanging Up Dialling Smart Leased- Line Mode Calling and AnsweringUsing &L1Leased Line Operations Auto Leased Line Operation &L2 or &L3 Wire Leased Line setup via audio port Selecting Communications Speeds Setting Up your Modem Hints for Unix Computers and Multiplexers Dialling in Dumb Mode Using the Talk /Data Button to Dial Using DTR to Dial Answering Calls in Dumb Mode Manual Answering AT%F Option SwitchesSwitch Description Selecting V.25bis Operation 25bis Operations Overridden Settings 25bis CommandsData Formats Verbal Meaning 25bis Indications Hanging Up Direct Dialling Selecting Speeds Asynchronous Notes DB25 Pin SignalModem Cable Synchronous Character Encoding Hdlc Notes Distinctive Ring Commands AT-SDR=0AT-SDR=7 Enabling the Caller ID Function Caller ID Integrating Caller ID into the Security Database AT#CID?AT#CID=? Distinctive Ringing ‘Tune’ Option Call Log Format Call Logging +++ Escape Sequence OptionsSee Also ATA, ATD, ATH, ATZ, AT&T Remote Access Sequence Request remote access AT? Interactive Command Help AT?AT?&T Repeat Last Command ATA Answer ATBn Select Communications Standard Command Speed B10 32 at 4800bps B11 32 at 7200bps B12 See Also Example ATD Dial Pause Dial Modifiers Return to local command state Reverse mode@ wait for quiet answer Last number redial Or disable calling tonesInitiate MNP 10 at 1200 bps MNP 10 Cellular Option Hook flash =n dial stored phone number nWait for dial tone See Also ATE Echo RangeATE0 ATH2 ATH Hang UpATH0 ATH1 ATI Identity ATL1 ATL Speaker Volume ControlRange See Also ATL0 ATM3 ATM MonitorATM0 ATM2 ATO Return to On-line State ATO30 ATO27ATO28 ATO29 ATQ Quiet Suppress Response Codes ATQ1ATQ2 ATR Set Terminal Speed ATR57 ATR26ATR28 ATR38 ATSn? Display S Register Value ATSn= Set S Register Value Verbal Numeric Meaning ATV Verbal Response Codes ATW Connection Speed Information ATW0ATW1 ATX Extended Response Codes Command ATZ2 ATZn Restore Configuration ProfileATZ0 ATZ1 Range Options AT&B Character Length AT&C3 AT&C Controlling Data Carrier DetectAT&C0 AT&C2 AT&D3 AT&D Controlling Data Terminal ReadyAT&D0 AT&D1 AT&F. Reinitialise Modem AT&F2 AT&F Restore Factory DefaultsAT&F0 AT&F1 AT&G Guard Tone AT&G1AT&G2 AT&H1 AT&H Clock Control AT&K5 AT&K Flow ControlAT&K0 AT&K4 Modem to the computer AT&L Leased Line AT&M4 AT&M Synchronous/Asynchronous ModeAT&M1 AT&M2 Range See Also AT&N0 AT&N Abort Connection AT&R1 AT&R RTS/CTS Control AT&S Controlling DSR AT&S1AT&S2 AT&Vn View Active Configuration Profile AT&W2 AT&Wn Write Configuration ParametersAT&W0 AT&W1 AT&X Transmit Clock AT&X1AT&X2 AT&Y2 AT&Yn Select Stored Profile on Power UpAT&Y0 AT&Y1 AT&Z Stored Phone Number AT#A Universal Remote Access AT#A0AT#A1 Range AT#B1 AT#B 1200bps Originate Mode AT#C0 AT#C V.25 Calling Tones AT#CID Caller ID AT#CID3 AT#CID0AT#CID1 AT#CID2 AT#D1 AT#D V.25bis Direct Calling AT#E3 AT#E EncryptionAT#E1 AT#E2 AT#H Display Help AT#I1 AT#I V.22bis Leased Line AT#J0 AT#J V.42 Capability Checking AT#K MNP 10 mode AT#K0AT#K2 AT#M3 AT#M Command Mode SelectionAT#M1 AT#M2 AT#N1 AT#N V.25bis Character Encoding AT#O3 AT#O Buffer OverflowAT#O1 AT#O2 AT#Q V.25bis Terminal Speed AT#R Enable Remote Control AT#S Security Menu AT#U1 AT#U V.25bis Character Set AT#V0 AT#V Verifier AT%B2 AT%B AutoAnswer Setting Examples AT%C Compression Control AT%D Set Disconnect Delay AT%E Auto EQM Retrain AT%E0AT%E1 AT%F0 AT%F DTR/DSR override AT%H3 AT%H MNP 10 Negotiation SpeedAT%H1 AT%H2 AT%K1 AT%K CTS During Dial and Handshake AT%L Display Line Signal Level 11-19 AT%Ln Transmit Level Data Mode AT%M1 AT%M Mode LED Indication AT%N Non-Standard Terminal Speeds AT%N1AT%N2 AT%P1 AT%P Connect Message Timing AT%Q AT%Q Line Signal Quality AT%R CTS Override AT%R1AT%R2 AT%S1 AT%S DSR Override AT%T1 AT%T DCD Override AT%U V.42 Response Codes AT%U1AT%U2 AT%W1 AT%W Welcome Message AT\A2 AT\A MNP Block SizeAT\A0 AT\A1 Default See Also AT\Bn Generate BreakAT\B4 AT\J1 AT\J Auto-Reliable Fallback AT\K Break Control Default AT\N Asynchronous Operating Mode See Also AT\Q Extended Flow Control AT\S AT\S Display Active Configuration AT\Tn Inactivity Timer Data Mode AT\V9 AT\V Error Correction Response CodesAT\V1 AT\V8 AT\X1 AT\X XON/XOFF Pass Through AT*K Select Primary DES KEY from Stored Keys Default Range See Also AT*R1 AT*R V.13 Remote RTS Signalling AT*S Change Current User Password AT*T1 AT*T Auto Call Redial AT*V1 AT*V Maximum V.42bis Dictionary Size AT*W Welcome Message Text AT*Y1 AT*Y Escape Seq. Detection in Sync AT+ICF Character Framing and Parity Select Mod AT+MS Select Modulation Automode Minrate MaxrateXlaw Rbsignaling Connecting with 56k technologyNn Automode +MS AT+MS=? Reporting Supports Options AT-Q0 AT-Q MNP10 Fallback to V.22bis AT-DATE Time & Date AT-LOG Call Log AT-LOGAT-LOG2 ATE V.32 compromise Equaliser 25BIS CIC Connect Incoming Call Modifier Meaning 25BIS CRN Dial CRS command Dial Stored Number Register 25BIS CRS Dial Stored Number 25BIS DIC Disregard Incoming Call CRS 25BIS PRN Stored Phone Number 25BIS RST Reset Register Settings and Modem Memory IntroductionReading and Changing S Registers Page ATS0 Rings Before Answer Default Range ATS1 Ring Count ATS2 Escape Sequence Character ATS3 Carriage Return Character Default Example ATS4 Line Feed Character ATS5 Backspace Character ATS6 Dial Tone Wait Time ATS7 Wait for Carrier ATS8 Pause Dial Modifier Delay ATS9 Carrier Detect Response Time ATS10 Lost Carrier/Hang Up Delay ATS11 Dtmf Tone Timing ATS12 Escape Sequence Guard Time ATS16 ATS16 Test in Progress read only ATS18 Test Timer ATS25 DTR Loss Detection ATS26 RTS/CTS Delay ATS27 Delay Before Dial ATS29 Hook Flash Duration ATS30 Inactivity Timer Data ModeVoice Mode ATS105Voice ‘Dead-man’ Timer ATS33 EQM Threshold Value ATS38 Disconnect Delay Value Meaning ATS42 Modem Disconnect Reason ATS43 Break Sequence Length ATS45 V.22bis EQM Threshold Value ATS57 DTR High Detection ATS62 V.42 Detection Timer ATS66 Remote Access Guard Time ATS67 Remote Access Character ATS69 Command Line Time-out ATS71 Ignore Incoming Call ATS74 Disconnect Reason for Prev. Call ATS80 Flow Control High Water Mark ATS81 Flow Control Low Water Mark ATS82 Failsafe Flow Control Overrun ATS95 Extended Response Codes ATS96 Help Page Width ATS97 Help Page Length ATS30 ATS105 Voice ‘Dead Man’ Timer EQM ATS122 AutoRateChange ATS123 AutoRateChange ATS124 Duration EQM Modem Response Codes 25bis Indications Modem Response Codes Request To Send RTS Pin Signal Ground SG PinTransmit Data TxD Pin Receive Data RxD Pin Receive Clock RxC Pin Ring Indicator RI PinData Carrier Detect DCD Pin Transmit Clock TxC Pin Standard RS-232 Examples General Commands Abbreviated Command ListPage Answer mode Page #CID0 S0=0 No AutoAnswer Mod Possible Rates bps Dial Modifiers Distinctive Ring Commands AbbreviatedCommandList Page Ascii Ansi BBS BPS Clock ContentionCharacter Set Clear to Send CTS CPU CRTCTS DCE DCD DTE Mail EbcdicEeprom EIA ETX ENQ Hdlc Host Computer HeaderHertz Hz Horizontal Redundancy Checking HRC ISO ITULED Loopback Log onLog Off Longitudinal Redundancy Check Pabx NAK PEP PBX RAM Prom SIG ROMRTS Sdlc STX SOH SYN XON/XOFF ZModem Caller ID Command Sets Humidity Error CorrectionEncryption Environmental Product Warranty Return Merchandise Authorization RMA Procedure RMA Procedure Department of Canada Statement Compliances Compliances