Sony Ericsson GTR-64 Serial Data Signals RD, TD, Control Signals RTS, CTS, DTR, DSR, DCD, RI

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GTR64

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3.6.1 Serial Data

The modem supports the standard data character format of

1 start bit, 7 or 8 data bits, 1 optional parity bit, 1 or 2 stop bits

Programmable baud rate

Auto-configuration mode with auto-baud and auto-format operation

In line with serial communication terminology the module is the data circuit-terminating equipment (DCE) and the external application or computer is the data terminating equipment (DTE).

3.6.2 Serial Data Signals - RD, TD

The default baud rate of the UARTs is auto-baud. Baud rates of between 600 bauds to 460 kbauds are possible. The wireless modem also supports 3GPP TS 27.010 multiplexing protocol, which starts when the appropriate command is sent.

Serial Data From Modem (RD)

RD is an output signal that the modem uses to send data to the application.

Serial Data To Modem (TD)

TD is an input signal, used by the application to send data to the modem.

3.6.3 Control Signals - RTS, CTS, DTR, DSR, DCD, RI

Depending upon the user application, some, all, or none of the control signals may be needed. Each of the control signals can alternatively be configured as a general purpose IO. When hardware flow control is not used in communications between the application and the wireless modem, some applications may require RTS and CTS to be connected to each other at the wireless modem. Users should familiarize themselves with the specific implementation of their UART.

RTS and CTS are capable of transmitting at 1/10th of the data transmission speed for data rates up to 460kbps (byte-oriented flow control mechanism).

Request to Send (RTS)

Used to condition the DCE for data transmission. The default level is high by internal pull up. The exact behaviour of RTS is defined by an AT command. Software or hardware control can be selected. Hardware flow is the default control.

The application must pull RTS low to communicate with the modem.

The modem will respond by asserting CTS low, indicating it is ready for communication.

Clear To Send (CTS)

CTS indicates that the DCE is ready to transmit data. The default level is high. You can define the exact behaviour of CTS through an AT command, and can select software or hardware flow control.

Data Terminal Ready (DTR)

DTR indicates that the DTE is ready to transmit and receive data. It also acts as a hardware ‘hang-up’, terminating calls when switched high.The signal is active low. You can define the exact behaviour of DTR with an AT command.

The DTR line can also be used to switch on the modem when activated for 0.2 seconds. The DTR line must be deactivated prior to switching off the modem to ensure it switches off (powers down) correctly.

Data Set Ready (DSR)

An active DSR signal is sent from the modem to the application (DTE) to confirm that a communications path has been established. DSR has two modes of operation, settable using the AT command AT&S.

GTR64 Integrators Manual V.1.2 Pag. 18

Preliminary. Subject to change without prior notice

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Contents Terminal GTR64Service and Support Important informationSecond EDITION. July GTR-64 Wireless modems in a Communication System Installation of the Modem Introduction DescriptionData Features Radio FeaturesGeneral Features HighlightsShort Message Service SMS Features GTR-64 Wireless modems in a Communication SystemVoice Features Internet ProtocolsMain Blocks in a Wireless System external micro-controller Types of Mobile Station Main Features and ServicesShort Message Service GmskData PrecautionsPower Consumption Gprs Multi-Slot SupportMechanical Description OverviewDimensions Dimensions of the GTR64 terminal in mmPower Conector Signal Dir Limits DescriptionElectrical Description Pin Signal Dir Description Audio ConectorMini USB Connector Electrical characteristics are given in the table belowAntenna Conector SIM card readerParameter Limit Description Pin Signal Dir Voltage Description Levels RS232 Serial PortSerial Data Signals RD, TD Control Signals RTS, CTS, DTR, DSR, DCD, RISerial Data Dir Max. Voltage Description Signal Limits Expansion I/O portPin ADC ServiceGTR64 RI1 Pin Name Direction FunctionParameter Min Typ Max Unit SPI BusGeneral Purpose IO Software Updates Real Time ClockResetting the Modem Switching On the ModemSwitching Off the Modem OperationImplementation FeaturesEmbedded Applications LimitationsGeneral precautions Safety and Product CareSafety instructions 2 M2mpower IDE Integrated Developers EnvironmentSIM card precautions Antenna precautionsRadio Frequency RF exposure and SAR Signal strength Installation of the ModemWhere to install the modem Personal Medical DevicesHow to install the modem AntennaAntenna type AccessoriesAntenna placement Antenna cableMagnetic Dual Band Antenna 900/1800MHz Opaniel TechnologiesRight angle short antenna SCL RD3 TD3 SDA Vrtc Alarm VrefService GND RI1/IO8CSD CBMCBS DCEAT Command Summary AT command DescriptionAT*E2CMGR AT*E2RESETGTR64 AT*E2CMGL AT*E2EAMSPage AT+CHLD y AT+CSMS GTR64 AT+CSIMAT+CSMP AT+CSNS