Datasheet

Copyright © 2011 Future Technology Devices International Limited 12
Document Reference No.: FT_000204
DB9-USB Datasheet
Version 2.1
Clearance No.: FTDI# 130
3.1.2 Female DB9 UART Connector Signals
The DB9-USB-X-F can be used to replace a female DB9 connector used for transmitting UART signals.
Table 2.2 gives the pin out description of each pin/pad of an UART connector/footprint.
Pin
Number
Pin Type of
DB9-USB
module
Pad Type at
application PCB
Description
1
Input
Output
DCD = Data Carrier Detect
(this is an input to the DB9-USB-X-F from the
application DCD output)
2
Input
Output
RXD = Receive Data
(this is an input to the DB9-USB-X-F from the
application Tx output, normally labelled RXD in
DCE convention)
3
Output
Input
TXD = Transmit Data
(this is an output to the DB9-USB-X-F from the
application Rx input, normally labelled TXD in DCE
convention)
4
Output
Input
DTR = Data Terminal Ready
(this is an output to the DB9-USB-X-F from the
application DSR input, normally labelled DTR in
DCE convention)
5
Ground
Ground
GND = RS232 signal ground
6
Input
Output
DSR = Data Set Ready
(this is an input to the DB9-USB-X-F from the
application DTR output, normally labelled DSR in
DCE convention)
7
Output
Input
RTS = Request To Send
(this is an output to the DB9-USB-X-F from the
application CTS input, normally labelled RTS in
DCE convention)
8
Input
Output
CTS = Clear To Send
(this is an input to the DB9-USB-X-F from the
application RTS output, normally labelled CTS in
DCE convention)
9
Input
Output
RI = Ring Indicator
(this is an input to the DB9-USB-X-F from the
application RI output)
Shield
Ground
Case Ground
Drain = typically connected to the host PC case
Table 2.2 – Female DB9 UART Signal Description