Revision: A1.1
The design and specifications are subject to change without notice for improvement
www.CommFront.com
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INTRODUCTION
This USB
RS485 converter is a port-powered bi-directional USB to RS485 converter, which can be
used to convert any standard full-duplex USB port into a two-wire half-duplex RS485 port and vice
versa. The unit can be used to communicate with one loop of up to 128 units of RS485 devices. The
unit is powered from the USB port and it supports data auto-sensing & self-adjusting, no baud rate
setting is required. And with the data direction auto-turnaround technology, no external power or
flow control is required for RS485 communications.
The unit uses the latest FTDI chipset and is fully compatible with Windows 7/Vista/XP/Server2008
/2003/2000/98 (32-bit), Windows 7/Vista/XP/Server2008/2003 (64-bit), Win CE, Mac, and Linux.
Note: the latest drivers (chipset FT232B) are available at
http://www.ftdichip.com/Drivers/VCP.htm
.
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FEATURES
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Adds one RS-485 port to your USB port.
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Communicate with one loop of up to 128 units of RS485 devices.
•
Built-in 120Ω end-of-line terminator for reliability and easy installation.
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Data direction auto-turnaround, no flow control is required.
•
Supports 300 to 115,200 baud (auto-sensing and self-adjusting).
•
Supports Windows 7/Vista/XP/Server2008/Server2003/2000/98 (32-bit), Windows 7/Vista/XP/
Server2008/Server2003 (64-bit), Win CE, Mac, and Linux.
•
Supports remote wakeup and power management.
•
Plug and play (hot-pluggable, data format auto-sensing and self-adjusting).
•
Port-powered, no external power required.
•
No IRQs required, no IRQ conflicts.
•
Surface Mount Technology manufactured to RoHS and ISO-9001 standards.
•
Safety: Strictly certified by SGS/TUV; 5-year manufacturer’s warranty.
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SPECIFICATIONS
Compatibility:
USB 2.0 (backward compatible) and EIA/TIA RS-485 standards
Power Source:
From USB port
Current Consumption:
Less than 100mA
Baud Rates:
300 to 115,200bps (auto-sensing and self-adjusting)
Distance:
USB side: 10ft (3m); RS-485 side: Depending on the power from
USB port, will transmit up to 4000ft (1.2km) at 19,200bps
Connectors:
USB side: Type A female; RS-485 side: DB-9 male; Termination
board: DB-9 female and a 4-way terminal block
Maximum Number of Drops:
128
End-of-line Terminator:
120Ω (Built-in)
Dimensions (HxWxD):
0.63 x 1.3 x 5.5 in (16 x 32 x 140 mm) (excluding cable)
Cable Length:
3.3 ft (1 m)
Weight:
3.5 oz (100 g)
Operating Temperature:
32ºF to 95ºF (0ºC to 35ºC)
Operating Humidity:
Up to 90% RH (no condensation)
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PIN ASSIGNMENT
RS-485 (DB-9 Male Connector / Termination Board):
DB-9 Pin:
1
3
5
9
6,7
Terminal Block:
A+
B-
GND
+5V
Jumper (120)
Function:
RS485+ RS485-
GND
+5V
measurement
Terminate/remove Jumper 120 to
turn ON/OFF the 120Ω end-of-line
terminator
USB
RS-485 Converter
Part Number: USB-232-1+CVT-485-1
Communications made easy
