English
Language : 

DB9-USB-RS232 Datasheet, PDF (9/27 Pages) Future Technology Devices International Ltd. – DB9-USB-RS232 Module Male & Female
Document Reference No.: FT_000204
DB9-USB-RS232 Datasheet
Version 1.2
Clearance No.: FTDI# 130
2.1.3 Replacing an RS232 DB9 FEMALE (DCE defined) Connector
The DB9-USB-RS232-F can be used to replace a female DB9 connector used for transmitting RS232
protocol. With the DB9-USB-RS232-F in place instead of the standard USB connector a USB bridge is
created, this allow the application to communicate with other devices via USB. Installing the DB9-USB-
RS232-F is simple. Simply replace the female DB9 connector with the DB9-USB-RS232-F connector
(same PCB footprint), install drivers and the device is ready to use.
Table 2.3 gives the pin out description of each pad of an RS232 footprint. Figure 2.3 gives a description
of the connections between the DB9-USB-RS232-F and the footprint of a female DB9 module. Figure 2.4
Illustrates the connection made to an example PCB.
Pin
Number
1
2
3
4
5
6
7
8
9
Shield
Pin Type of DB9-
USB-RS232
module
Input
Input
Output
Output
Ground
Input
Output
Input
Input
Ground
Pin Type at
application PCB
Description
Output
Output
Input
Input
Ground
Output
Input
Output
Output
Case Ground
DCD = Data Carrier Detect
(this is an input to the DB9-USB-RS232-F from
the application DCD output)
RXD = Receive Data
(this is an input to the DB9-USB-RS232-F from
the application Tx output, normally labelled RXD
in DCE convention)
TXD = Transmit Data
(this is an output to the DB9-USB-RS232-F from
the application Rx input, normally labelled TXD in
DCE convention)
DTR = Data Terminal Ready
(this is an output to the DB9-USB-RS232-F from
the application DSR input, normally labelled DTR
in DCE convention)
GND = RS232 signal ground
DSR = Data Set Ready
(this is an input to the DB9-USB-RS232-F from
the application DTR output, normally labelled DSR
in DCE convention)
RTS = Request To Send
(this is an output to the DB9-USB-RS232-F from
the application CTS input, normally labelled RTS
in DCE convention)
CTS = Clear To Send
(this is an input to the DB9-USB-RS232-F from
the application RTS output, normally labelled CTS
in DCE convention)
RI = Ring Indicator
(this is an input to the DB9-USB-RS232-F from
the application RI output)
Drain = typically connected to the host PC case
Table 2.3 – A Female RS232 DB9 footprint Pin-Out
Copyright © 2010 Future Technology Devices International Limited
8