DS_USB-COM422-PLUS1 Datasheet, PDF (7/23 Pages) List of Unclassifed Manufacturers – Future Technology Devices International Ltd

2 Installation
Document Reference No.: FT_000131
USB-COM422-PLUS1 Datasheet
Version 1.1
Clearance No.: FTDI# 94
2.1 Example Applications and Configurations
2.1.1 Wiring
Insert the A-plug into an available USB Host or Hub port. Insert the B-plug into the B-receptacle on the
USB-COM422-Plus1.
The USB-COM422-Plus1 follows EIA-422 standard as a Data Terminal Equipment (DTE) device. If the
RS422 equipment being connected is a Data Communication Equipment (DCE) device, it’s typical that a
straight-through cable can be used.
DTE Pin Number Signal Name
Expected Connect Signal
1
TXD- = Transmit Data,
negative polarity
RXD-
2
TXD+ = Transmit Data,
positive polarity
RXD+
3
RXD+ = Receive Data,
positive polarity
TXD+
4
RXD- = Receive Data,
negative polarity
TXD-
5
GND = signal ground
GND
6
RTS- = Request To Send,
negative polarity
CTS-
7
RTS+ = Request To Send,
positive polarity
CTS+
8
CTS+ = Clear To Send,
positive polarity
RTS+
9
CTS- = Clear To Send,
RTS-
negative polarity
Table 2.1 RS422 DTE to DCE connection with straight-through cable
Some serial devices may require certain handshake signals be connected. Refer to your device manual
for cabling details.
2.2 Device Driver Installation
The USB-COM422-Plus1 module drivers are available for download from:
www.ftdichip.com
2.2.1 Microsoft Windows
With the device drivers being Windows Hardware Quality Labs (WHQL) certified, they are also available
through download directly from the Microsoft^® Windows^® Update service. This is the best choice when
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