Copyright © 2010 Future Technology Devices International Limited

13

Document Reference No.: FT_000118

USB-COM232-PLUS1 Datasheet

Version 1.2

Clearance No.: FTDI# 76

3 Connections

3.1 External Connectors

3.1.1 USB

The USB-COM232-Plus1 is a downstream USB 2.0 Device. A standard USB Series “B” receptacle is

mounted inside the USB-F-1001 to facilitate connection to an upstream USB Host or Hub.

Pin Number

Pin Type

Description

1

Power

VBUS – USB Power provided from upstream USB Host or Hub

2

Bidirectional

D– = USB data signal, negative polarity

3

Bidirectional

D+ = USB data signal, positive polarity

4

Ground

GND = USB signal ground

Shield

Case Ground

Drain = typically connected to the host PC case

Table 3.1 – USB "B" Receptacle Pin-Out

3.1.2 RS232

The RS232 port is configured as Data Terminal Equipment (DTE), with a 9-contact D-Sub Pin connector.

Pin assignments are according to TIA/EIA-574 which formally defines the assignments for a COM port

found on many personal computers. In addition, Ring Indicator (RI) may be re-assigned to provide

+5VDC to an external device with a maximum current draw of 250mA once the USB-COM232-Plus1 has

been enumerated by the system.

Pin Number

Pin Type

Description

1

Input

DCD = Data Carrier Detect

2

Input

RXD = Receive Data

3

Output

TXD = Transmit Data

4

Output

DTR = Data Terminal Ready

5

Ground

GND = RS232 signal ground

6

Input

DSR = Data Set Ready

7

Output

RTS = Request To Send

8

Input

CTS = Clear To Send

9

Input / Power

RI = Ring Indicator or +5VDC @ 250mA max

Shield

Case Ground

Drain = typically connected to the host PC case

Table 3.2 – DE-9P RS232 Pin-Out