Xircom An Intel Company GEM3501 사용자 설명서

Core Engine GSM/GPRS Modem Developer Guide Preliminary Draft: 7/6/2001

6

Part Number: 07100026, Revision: 002

Confidential

© 2001 Xircom, Inc., an Intel company All rights reserved.
All trademarks and copyrights are the property of Xircom, Inc., an Intel company

4.7 Secondary Serial Interface [P2] ..................................................................................18

4.8 Primary Audio Interface [P1] .......................................................................................19

4.9 Secondary Audio Interface [J1] ...................................................................................20

4.10 Audio Interface Select [JP2]......................................................................................20

4.11 Subscriber Interface Module [J3] ..............................................................................20

4.12 Status Indication [DS1] .............................................................................................20

5 POWER....................................................................................................................... 22

5.1 Power Up Sequence...................................................................................................22

5.2 Power Management....................................................................................................22

5.2.1 Power Modes ......................................................................................................22

5.2.2 Hardware Signals................................................................................................24

5.2.3 Software Commands...........................................................................................24

5.3 Transmit Power ..........................................................................................................25

6 SERIAL COMMUNICATIONS .................................................................................... 26

6.1 Supported Serial Port Configurations..........................................................................26

6.1.1 Single Port Configuration ....................................................................................26

6.1.2 Dual Port Configuration .......................................................................................27

7 AUDIO......................................................................................................................... 29

7.1 Audio Path Selection ..................................................................................................29

7.1.1 Hardware Selection of Audio Path.......................................................................29

7.1.2 Software Selection of Audio Path ........................................................................29

7.2 Microphone Input ........................................................................................................29

7.3 Speaker Output ..........................................................................................................30

7.4 Audio Circuit Implementation ......................................................................................31

7.4.1 Example Single-Ended Microphone Circuit .........................................................31

7.4.2 Example Differential Microphone Circuit..............................................................32

7.5 Microphone Cable Considerations ..............................................................................32

8 RF ANTENNA............................................................................................................. 33

8.1 Antenna Connector.....................................................................................................33

8.2 Antenna Selection.......................................................................................................33

8.3 Antenna Performance Guidelines ...............................................................................33

8.3.1 Antenna Impedance Match .................................................................................33

8.3.2 Antenna Pattern and Gain...................................................................................34

8.3.3 Antenna Beam Width ..........................................................................................34