Ericsson R320s White Paper page 20

C C C C o o o o n n n n n n n n e e e e c c c c t t t t i i i i o o o o n n n n v v v v i i i i a a a a c c c c a a a a b b b b l l l l e e e e
The infrared connection is not always the best solution for connecting with a PC/PDA, or in
fact, even possible. The cable DRS-10 provides the same connectivity between the phone and
another unit.
The DRS-10 cable supports a subset of the signals in the RS-232 standard, as detailed below.
Signal in RS-232
CD (Carrier Detect)
CTS (Clear To Send)
DSR (Data Service Ready)
DTR (Data Terminal Ready)
GND (Signal Ground)
RI (Ring Indication)
RTS (Request To Send)
Rx (Received Data)
Tx (Transmitted Data)
G G G G S S S S M M M M D D D D a a a a t t t t a a a a
The built-in data capability turns the phone into a modem when connected to a PC/PDA. To put
it simple GSM Data is the ability to send data or fax information over the GSM (Global System
for Mobile communication) network. Data over GSM offers new opportunities for both GSM
network operators and mobile workers alike. By using GSM to send and receive data or faxes,
mobile employees have access to a level of geographic mobility previously unobtainable.
The key beneÞts of GSM Data include:
¥ GSM data can be used from any location at any time.
¥ Ease of use for international travellers.
¥ GSM data offers a use anytime, anywhere capability, unmatched by Þxed telephone net-
works.
¥ The cost of using GSM data is reducing over time.
¥ Interworking with ISDN
One of the key advantages that GSM can offer users, is its ability to interwork with ISDN. This
is a core feature of the GSM standard, which has been developed to interwork seamlessly with
ISDN. Interworking between the ISDN and GSM networks is made possible by using a techni-
que known as rate adaptation. If the ISDN terminal adaptor being called by the GSM terminal is
capable of supporting V.110, i t can adapt the 9,600 bps data from the GSM terminal into 64000
bps ISDN data. This is achieved by adding additional bits to the GSM data effectively packing
out the data.
GSM was developed to interwork with the Integrated Services Digital Network (ISDN). ISDN
uses a technique known as rate adaptation to convert the slower GSM data up to 64000 bps
ISDN data using the International Telecommunications Union (ITU) V.110 rate adaptation pro-
tocol, which is a standard for ISDN terminals. As a result when a data call is made from GSM
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Support in DRS-10
No. Set statically
Yes
Statically connected with DTR
Statically connected with DSR
Yes
No. Set statically
Yes
Yes
Yes