Sony Ericsson T312 Cell Phone User Manual


 
White Paper T310/T312
23 January 2003
Using GPRS in the T310/T312
Instead of occupying an entire voice channel for
the duration of a data session, the T310/T312
sends/receives data in small packets, as needed,
much like IP on the Internet. Because of this, the
T310/T312 has data transmission abilities
summoned by the application in use on an as-
needed basis.
The GPRS specification includes four coding
schemes CS1, CS2, CS3 and CS4 that allow
theoretical data speeds of 9,050 bps, 13,400 bps,
15,600 bps and 21,400 bps respectively. The T310/
T312 works with all four coding schemes, but data
speed will naturally vary according to network
configuration. At the moment, CS-3 and CS-4 are
not supported in any live network, i e present
speed is limited to 40,200 bps.
Information about the identity of the phone and the
characteristics of the connection are described in
the PDP (Packet Data Protocol) context. This
information is stored both in the phone and in the
mobile network, so that each phone is identified
and visible to the system.
Using GPRS with the T310/T312 has
several advantages, for example:
All connection settings can be managed by
using the data connections feature.
High speed
Cost efficient when downloading large files,
images etc.
Use transmission capacity only when needed,
thus reducing costs.
WAP over GPRS
Access the Internet via WAP at high speed.
E-mail over GPRS
Data communication
Transfer data and access the Internet or an
intranet with a PC, PDA or handheld device
connected via infrared.
Receive GPRS configuration settings from the
provider over the air, OTA, making manual
configuration unnecessary.
User controlled settings
Take advantage of full user control in the data
connections menu, establishing multiple
descriptions and accessing advanced settings
for GPRS.
Modem and AT commands
The T310/T312 contains a complete GSM/GPRS
modem. This provides data and e-mail
communication, as well as Internet/intranet access,
for a connected PC, PDA or handheld device. Once
the PC/PDA is connected to the phone using
infrared, and the appropriate software is installed,
the modem in the phone works in a similar way to a
PC Card modem, or an external modem.
In the T310/T312, AT commands are used for:
controlling the data communication between
the PC and the remote service
configuring and requesting settings and behav-
iours in the phone, from a connected PC or PDA
GSM data communication
The built-in data capability turns the phone into a
modem when connected to a PC/PDA. The T310/
T312 offers the user data connection anytime,
anywhere, unmatched by fixed telephone
networks. Each GSM channel is divided into eight
repeating time slots. A normal GSM voice or data
call is circuit switched, and only one time slot is
used for each call. The data speed is therefore