Copyright © 2010 Future Technology Devices International Limited

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Document Reference No.: FT_000136

USB-COM485-PLUS2 Datasheet

Version 1.3

Clearance No.: FTDI#104

2 Installation

2.1 Example Applications and Configurations

2.1.1 Wiring

Insert the A-plug into an available USB Host or Hub port. Insert the mini-B-plug into the USB mini-B-

receptacle on the USB-COM485-PLUS2.

DTE Pin Number

Signal Name

Expected Connect Signal

1

DATA- = Transmit/Receive

Data, negative polarity

Also Terminator 2

DATA-

Pin 2 of 120R Terminating Resistor. Only Required if the USB-

COM485-PLUS2 is the first or last device in a multi-drop RS485

System, to meet RS485 Termination Requirements.

2

DATA+ = Transmit/Receive

Data, positive polarity

DATA+

3

Terminator 1

Pin 1 of 120R Terminating Resistor. Only Required if the USB-

COM485-PLUS2 is the first or last device in a multi-drop RS485

System, to meet RS485 Termination Requirements.

4

N/A

N/A

5

GND = signal ground

GND

6

N/A

N/A

7

echo enable terminal 1

Local echo function control. Connect to pin 8 can disable the

local echo function. The local echo is enabled by default.

8

echo enable terminal 2

Local echo function control. Connect to pin7 can disable the

local echo function. The local echo is enabled by default.

9

PWR = +5V DC output

PWR

Table 2.1 – RS485 DTE to DCE connection

Figure 2.1 USB-COM485-PLUS2 Termination resistor and echo disable