User Manual

GM47/48 Technical description

BA/SEM/MS 02:0004 Rev B

Clear To Send (CTS)

CTS is an output from the module. The signals on this circuit shall be

used to indicate that the DCE (the module when used for data

transmission purposes) is ready to transmit data. Default level is high.

The exact behaviour of CTS shall be defined by an AT command.

Software or hardware flow control can be selected.

This is a Dig. 2.75 CMOS Output and general characteristics are

applicable.

Tip: if only software flow control is to be used it becomes necessary

to assert RTS low or to connect RTS to CTS at the module.

Parameter Limit

Application load capacitance < 500 pF

Application load resistance

> 1 MΩ

Data Terminal Ready (DTR)

DTR is an input to the module. Signals from the DTE on this circuit

indicate the DTE is ready to transmit and receive data. DTR also acts

as a hardware 'hang-up' so that calls are terminated if DTR is OFF

(high).

Default level is ON (low). The exact behaviour of DTR shall be

defined by AT commands.

This is a Dig. 2.75 CMOS Input and general characteristics are

applicable.

Data Carrier Detect (DCD)

DCD is an output from the module. An ON (low) signal shall indicate

that a valid carrier (data signal) is being received by the DCE

(module). The exact behaviour of DCD shall be defined by an AT

command.

This is a Dig. 2.75 CMOS Output and general characteristics are

applicable.

Ring Indicator (RI)

RI is an output from the module. An ON (low) signal shall indicate a

ringing signal is being received by the DCE (module).

The functionality shall be selected by an AT command.

This is a Dig. 2.75 CMOS Output and general characteristics are

applicable.