Sony Ericsson GM48 Cell Phone User Manual


 
GM47/GM48 INTEGRATOR’S MANUAL
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LZT 123 7263 R1C
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 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.
Data Set Ready (DSR)
No DSR signal is provided. Use any DGND connection for this
functionality.
2.8.4 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 module is turned on. These are:
the module is reprogrammed if UART2 is connected to a computer
running Sony Ericsson update software;
the module 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.
Transmitted Data 2 (TD2)
TD2 is used by the application to send data to the module 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.