Sony Ericsson T312 Benutzerhandbuch

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White Paper
 
 
T310/T312
24
January 2003
limited to 9,600 bps. For more information, see 
“Built-in GSM data modem technical data” on 
page 69.
High Speed Data gives a faster speed
High Speed Data (HSCSD) increases speeds for 
circuit switched data by allowing the phone to use 
a coding scheme with a high capacity, and to use 
two time slots for receiving data. The download 
speed is increased to up to 28,800 bps. The speed 
for sending data is limited to 14,400 bps. The data 
rate can be increased several times by the use of 
rate adaption, inter working with ISDN. This also 
provides additional features, such as quick call set-
up capability.
GPRS at high speed
With GPRS data is transmitted in packets. Pricing 
of GPRS may be dependent on the data 
transmitted, which means very low cost when no 
data is sent or received. When transmitting large 
amounts of data, it may be possible to increase 
bandwidth automatically to allow faster 
transmission speed, up to 40,200 bps download 
speed.
AT commands support
This section outlines the AT commands supported 
by the T310/T312. The information here can be of 
use for advanced users, to indicate the possibilities 
they have to:
develop new communications software
add the T310/T312 to an application’s list of 
compatible modems
adjust the settings of their mobile telephone and 
modem
The modem in the T310/T312 supports the V.25ter 
command set, which is the standard 
communication set used by modems.
The T310/T312 is compatible with industry de facto 
extensions, ETSI 07.05, 07.07 and 07.10.
Overview of AT command functions
AT commands are used to configure the mobile 
telephone, to request information about the current 
configuration or operational status of the mobile 
phone, and to test availability and request the 
range of valid parameters, when applicable, for an 
AT command.
The built-in modem can be set to any one of three 
modes of operation. These are:
Off-line command mode
The command mode for entry of AT commands, 
when the device is first turned on.
On-line data mode
Allows “normal” operation of the built-in modem, 
for exchanging data or facsimiles with a remote 
modem.
On-line command mode
For sending AT commands to the built-in modem 
while remaining connected to a remote modem.
The AT commands in the T310/T312 are 
grouped as follows:
Control and Identification
Call Control
Interface Commands
Data Compression
Mode Management
Audio Control
Accessory Menus
Accessory Authentication
Voice Call Control
Accessory Identification
GSM DTE-DCE Interface Commands
GSM Call Control
GSM Data
GSM High Speed Circuit Switched Data
GSM Network Services
GSM USSD
GSM Facility Lock
GSM Mobile Equipment, Control and Status
GSM Mobile Equipment Error Control
GSM SMS and PDU Mode
GSM GPRS
GSM Phone book
GSM Clock, Date and Alarm Handling