Future Technology Devices International Ltd
USB to RS485 Serial Converter Cable
Datasheet
Document Reference No.:
FT_000117
Version 1.4
Issue Date: 2010-05-27
Future Technology Devices International Limited (FTDI)
Unit1, 2 Seaward Place, Centurion Business Park,, Glasgow G41 1HH United Kingdom
Tel.: +44 (0) 141 429 2777 Fax: + 44 (0) 141 429 2758
E-Mail (Support):
support1@ftdichip.com
Web: http://www.ftdichip.com
Copyright © 2010 Future Technology Devices International Limited
Neither the whole nor any part of the information contained in, or the product described in this manual, may be adapted or reproduced
in any material or electronic form without the prior written consent of the copyright holder. This product and its documentation are
supplied on an as-is basis and no warranty as to their suitability for any particular purpose is either made or implied. Future Technology
Devices International Ltd will not accept any claim for damages howsoever arising as a result of use or failure of this product. Your
statutory rights are not affected. This product or any variant of it is not intended for use in any medical appliance, device or system in
which the failure of the product might reasonably be expected to result in personal injury. This document provides preliminary
information that may be subject to change without notice. No freedom to use patents or other intellectual property rights is implied by
the publication of this document. Future Technology Devices International Ltd, Unit1, 2 Seaward Place, Centurion Business Park,
Glasgow, G41 1HH, United Kingdom. Scotland Registered Number: SC136640
Copyright © 2010 Future Technology Devices International Limited
Document Reference No.: FT_000117
USB TO RS485 SERIAL CONVERTER CABLE Datasheet
Version 1.4
Clearance No.: FTDI
#75
1
Description
The
USB-RS485
cable is a USB to RS485 levels serial UART converter cable incorporating FTDI‟s
FT232RQ USB to serial UART interface IC device which handles all the USB signalling and protocols. The
cable provides a fast, simple way to connect devices with a RS485 interface to USB.
Each USB-RS485 cable contains a small internal electronic circuit board, utilising the FT232R, which is
encapsulated into the USB connector end of the cable. The FT232R datasheet,
DS_FT232R,
is available at
http://www.ftdichip.com.
The integrated electronics also include the RS485 transceiver plus Tx and Rx
LEDs which give a visual indication of traffic on the cable (if transparent USB connector specified).
The other end of the cable is bare, tinned wire ended connections by default, but can be customised
using different connectors to support various applications.
The USB-RS485 cable is designed for use at the end of an RS485 network up to approximately 10m. For
longer networks or placement of the USB-RS485 cable in the middle of an RS485 network it is
recommended that the attached wire is cut to 20cm or less to ensure signal integrity
Cables are FCC, CE, RoHS compliant.
The cable is USB powered and USB 2.0 full speed compatible. Each cable is 1.8m long and supports a
data transfer rate up to 3 Mbaud. Each cable supports the FTDIChip-ID™, with a unique USB serial
number programmed into the FT232R. This feature can be used to create a security or password
protected file transfer access using the cable. Further information and examples on this feature are
available at
http://www.ftdichip.com
under
FTDIChip-ID Projects.
The USB-RS485 cables require USB drivers, available free from
http://www.ftdichip.com,
which are
used to make the FT232R in the cable appear as a virtual COM port (VCP). This then allows the user to
communicate with the USB interface via a standard PC serial emulation port (for example TTY). Another
FTDI USB driver, the D2XX driver, can also be used with application software to directly access the
FT232R on the cable though a DLL. This is illustrated in the Figure 1.1
Various Connector
Options
TTY
USB_RS485
USB
Customised connectors
Wire Ended
VCP
Virtual COM Port
Various Connector
Options
Wire Ended
TTY
D2XX
Software application access to USB via D2XX
Figure 1.1 Using the USB-RS485 Cable
Copyright © 2010 Future Technology Devices International Limited
1
DLL
USB
Customised connectors
Document Reference No.: FT_000117
USB TO RS485 SERIAL CONVERTER CABLE Datasheet
Version 1.4
Clearance No.: FTDI
#75
2
Cable Part Numbers
The following
Table
2.1
gives details of the available USB-RS485 cables.
Part Number
Description
End Connector*
Cable details
USB
to UART cable with
RS485
USB-RS485-WE-1800-BT
level UART signals.
Black
cable,
Transparent
USB connector
USB
to UART cable with
RS485
level UART signals.
*
C =
cable colour (B black or
T
USB-RS485-CC-LLLL-CU-
X
U
= USB connector colour (T
transparent or
B
black)
X
= voltage (P is 5V, G is 0V)
Table 2.1 USB-RS485 Cables Descriptions and Part Numbers
*
Wire Ended
(no
connector)
1.8m
cable,6 core,
UL2464 24 AWG,
diam=5mm
LLLL = Length of
CC
= Connector
description.
cable.
transparent),
FTDI supports customised end connector designs. For more information, please contact FTDI Sales Team
(sales1@ftdichip.com)
2.1
Certifications
FTDI USB-RS485 cable is fully RoHs compliant as well as CE and FCC certified.
FCC Part 15, Subpart B, Class B. CISPR 22: 1997+A1: 2000, Class B. ICES-003: 2004, Class B.
ANSI C63.4-2003.
2.1
USB Compliant
The USB-R485 cables are fully compliant with the USB 2.0 specification.
Copyright © 2010 Future Technology Devices International Limited
2
Document Reference No.: FT_000117
USB TO RS485 SERIAL CONVERTER CABLE Datasheet
Version 1.4
Clearance No.: FTDI
#75
Table of Contents
1
2
Description ..................................................................................... 1
Cable Part Numbers ........................................................................ 2
2.1
2.1
Certifications ................................................................................................. 2
USB Compliant .............................................................................................. 2
The USB-R485 cable is fully compliant with the USB 2.0 specification. ................... 2
3
Typical Applications ........................................................................ 4
3.1
3.2
Driver Support .............................................................................................. 4
Features ........................................................................................................ 4
4
5
Features of FT232R applicable to USB-RS485 Cable ....................... 5
USB-RS485-WE-LLLL-CU-X ............................................................. 6
5.1
5.2
5.3
5.4
USB-RS485-WE Connections and Mechanical Details ..................................... 6
USB-RS485-WE Cable Signal Descriptions ..................................................... 7
USB-RS485-WE Electrical Parameters ........................................................... 7
Local Echo ..................................................................................................... 8
6
7
8
Cable PCB Block Diagram................................................................ 9
USB-RS485 – Schematic ............................................................... 10
Contact Information ..................................................................... 11
Appendix A - Cable EEPROM Configuration ......................................... 13
Appendix B - List of Figures and Tables.............................................. 14
Appendix C - Revision History ............................................................ 15
Copyright © 2010 Future Technology Devices International Limited
3
Document Reference No.: FT_000117
USB TO RS485 SERIAL CONVERTER CABLE Datasheet
Version 1.4
Clearance No.: FTDI
#75
3
Typical Applications
USB to serial RS485 level converter.
Upgrading legacy peripherals to USB.
Interface Microcontroller UART or I/O to USB.
Interface FPGA or PLD to USB.
USB Instrumentation PC interface.
USB industrial control.
USB password protected file transfers.
3.1
Driver Support
Royalty free VIRTUAL COM PORT
(VCP) DRIVERS for...
Windows 7 64-bit
Windows XP and XP 64-bit
Windows Vista and Vista 64-bit
Windows XP Embedded
Windows 98, 98SE, ME, 2000, Server 2003,
and Server 2008
Windows CE 4.2, 5.0 and 6.0
Mac OS 8/9, OS-X
Linux 2.4 and greater
Royalty free D2XX
Direct
Drivers
(USB Drivers + DLL S/W Interface)
Windows 7 64-bit
Windows XP and XP 64-bit
Windows Vista and Vista 64-bit
Windows XP Embedded
Windows 98, 98SE, ME, 2000, Server 2003,
and Server 2008
Windows CE 4.2, 5.0 and 6.0
Linux 2.4 and greater
Mac OS-X
The drivers listed above are all available to download for free from
www.ftdichip.com.
Various 3rd
Party Drivers are also available for other operating systems - see
www.ftdichip.com
for details.
3.2
Features
USB-RS485 converter cable provides a USB to
RS485 serial interface with customised end
connectors.
Entire USB protocol handled by the electronics
in the cable.
X-On / X-Off software handshaking.
Data transfer rates from 300 baud to 3 Mbaud.
Support for FT232R FTDIChip-ID™ feature for
improved security.
Low USB bandwidth consumption.
UHCI / OHCI / EHCI host controller compatible.
USB 2.0 Full Speed compatible.
-40°C to +85°C operating temperature range.
Cable length is 1.80m (6 feet).
ESD Protection for RS-485 I/O's
±15kV Human Body Model (HBM)
±15kV EN61000-4-2 Air Gap Discharge
±8kV EN61000-4-2 Contact Discharge
FCC and CE compliant.
Custom versions available on request (subject
to MOQ).
RoHS Compliant
Copyright © 2010 Future Technology Devices International Limited
4
EIA/TIA-485 communication interface with low
power requirements.
UART interface support for 7 or 8 data bits, 1
or 2 stop bits and odd / even / mark / space /
no parity.
Internal EEPROM with user writeable area.
FTDI‟s royalty-free VCP allow for
communication as a standard emulated COM
port and D2XX „direct‟ drivers provide DLL
application programming interface.
Visual indication of Tx and Rx traffic via LEDs in
the transparent USB connector.