Integrator's Manual GR47/GR48

5. SYSTEM CONNECTOR INTERFACE

LZT 123 7589 R1A

Data Terminal Ready (DTR)

DTR indicates that the DTE is ready to 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.

Data Set Ready (DSR)

DSR indicates that the DCE is ready to receive data. The signal is active

low.

Data Carrier Detect (DCD)

DCD indicates that the DCE is receiving a valid carrier (data signal) when

low.

Ring Indicator (RI)

RI indicates that a ringing signal is being received by the DCE when low.

You can define the exact behaviour of RI with an AT command.

5.9.4 UART2 - TD2, RD2

UART 2 consists of a full duplex serial communication port with

transmission and reception lines.

This communication port works in a mode called Operation and

Maintenance.

Operation and Maintenance mode works in combination with the

SERVICE signal. Two events are possible if the SERVICE signal is active

when the radio device is turned on. These are:

• the radio device is reprogrammed if UART2 is connected to a computer

running Sony Ericsson update software;

• the radio device enters logging mode and sends data to UART2 if no

reprogramming information is received.

Timing and electrical signals characteristics are the same as for UART1,

TD and RD, except for maximum baud rate which could increase to

921 kbps.

Transmitted Data 2 (TD2)

TD2 is used by the application to send data to the radio device via UART2.

It has the same electrical characteristics as TD.

Received Data 2 (RD2)

RD2 is used to send data to the application via UART2. It has the same

electrical characteristics as RD.