Xircom An Intel Company GEM3501 User Manual
Core Engine GSM/GPRS Modem Developer Guide Preliminary Draft: 7/6/2001
18
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
All trademarks and copyrights are the property of Xircom, Inc., an Intel company
4.6 Primary Serial Interface [P3]
The primary serial I/O interface (connector P3 on the carrier board) implements RS-232
using a DB-9 connector and supports auto baud capability from 2400 bps to 115200 bps
with hardware handshake flow control.
using a DB-9 connector and supports auto baud capability from 2400 bps to 115200 bps
with hardware handshake flow control.
Pin
Number
Signal
Name
Direction
Functionality
1
DCD0_DS
To CPE
Data Carrier Detect 0. DCE Output signal. Active low. Main
serial interface data carrier detect signal. Connects to a DTE,
CD, Carrier Detect pin.
2
RX0_DS
To CPE
Receive data 0. DCE Output signal. Main serial interface
transmit data signal. During idle or reset, signal will be a logic
1. Connects to a DTE, RX, receive data pin.
3
TX0_DS
From CPE
Transmit data 0. DCE Input signal. Active low. Main serial
interface receive data signal. During idle or reset, signal will
be a logic 1. Connects to a DTE, TX, transmit data pin.
4
DTR0_DS
From CPE
Data Terminal Ready 0. DCE Input signal. Active low. Main
serial interface data terminal ready signal. Connects to a
DTE, DTR, Data Terminal Ready pin.
5
GND_IN
From CPE
Electrical power return for digital and analog grounds.
6
DSR0_DS
To CPE
Data Set Ready 0. DCE Output signal. Active low. Main serial
interface data set ready signal. Connects to a DTE, DSR,
Data Set Ready pin.
7
RTS0_DS
From CPE
Request-To-Send 0. DCE Input signal. Active low. Main serial
interface request to send signal. Connects to a DTE, RTS,
Request-To-Send pin.
8
CTS0_DS
To CPE
Clear-To-Send 0. DCE Output signal. Active low. Main serial
interface clear to send signal. Connects to a DTE, CTS, Clear
to send pin.
9
RI0_DS
To CPE
Ring Indicator 0. DCE Output signal. Active low. Main serial
interface ring indicator signal. Connects to a DTE, RI, Ring
Indicator pin.
Table 3: Carrier Board Primary Serial Connector Pin Out
NOTE: The maximum length for the Primary Serial cable is 25 feet.
4.7 Secondary Serial Interface [P2]
The secondary serial I/O interface (connector P2 on the carrier board) implements RS-
232 using a DB-9 connector and supports auto baud capability from 2400 bps to 115200
bps with hardware handshake flow control.
232 using a DB-9 connector and supports auto baud capability from 2400 bps to 115200
bps with hardware handshake flow control.
Pin
Number
Signal
Name
Direction
Functionality