USB-COM485-PLUS-2 FTDI, USB-COM485-PLUS-2 Datasheet - Page 14

• Manufacturer Part Number: USB-COM485-PLUS-2
• Description: MODULE, DEV, USB-RS485, 2 COM PORT
• Manufacturer: FTDI
• Type: Developmentr

Specifications of USB-COM485-PLUS-2

• Mcu Supported Families: FT232R, FT2232, FT232BM
• Kit Features: Works With USB 1.1 & 2.0 Host And Hub Ports, FIFO
• Svhc: No SVHC (18-Jun-2010)
• 2.0 Host And Hub Ports, Fifo: 4KB Transmit Buffer, 4KB Receive Buffer
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

3.1.2 RS485
The RS485 ports are configured as Data Terminal Equipment (DTE), with a 9-contact D-Sub Pin
connector. Pin assignments are according to TIA/EIA-485. In addition, pin9 of DB9 provides +5VDC to
an external device with a maximum current draw of 450mA once the USB-COM485-PLUS2 has been
enumerated by the system. Both D-type connectors have a similar connection as described in Table 3.2.
Table 3.2 – DE-9P RS485 Pin-Out
Pin Number
1
2
3
4
5
6
7
8
9
PWR = +5V DC output
GND = signal ground
Copyright © 2010 Future Technology Devices International Limited
Input/Output
Input/Output
Pin Type
Output
Input
Input
N/A
N/A
Description
COM485-PLUS2 is the first or last device in a multi-drop RS485
COM485-PLUS2 is the first or last device in a multi-drop RS485
Pin 2 of 120R Terminating Resistor. Only Required if the USB-
Pin 1 of 120R Terminating Resistor. Only Required if the USB-
Pin 7 of the local echo control. Connect to pin 8 of the echo
Connect to pin 7 of the echo control to disable local echo.
control to disable local echo. Default is that local echo is
System, to meet RS485 Termination Requirements.
System, to meet RS485 Termination Requirements.
Default is that local echo is enabled.
enabled.
DATA+
DATA-
GND
PWR
Document Reference No.: FT_000136
N/A
N/A
USB-COM485-PLUS2 Datasheet
Clearance No.: FTDI#104
Version 1.2
13