Product Specifications; Features Of Vscom Usb-Com Pro Series; Serial Port Operation Modes - VSCOM USB-COM PRO User Manual

2 Introduction
2.2 Product Specifications
The VScom USB-COM PRO all have similar properties. Most important difference is the number
of serial ports. The maximum speed is 3 Mbit/s, which may be used in RS422 or RS485 mode,
RS232 is limited.
Host interface
Serial Ports
Signals
Max. Bitrates
Serial configurations
FIFO size
LED
Each of the serial ports may be used in 8 different operation modes as listed below. The Mode
LED related to each port is light in a certain color to indicate the mode used.
Mode
RS485 "4w"
RTS
RS485 "2w"
RTS no Echo
RS485 "2w"
RTS Echo
RS485 "4w"
auto
RS485 "2w"
auto no Echo
RS485 "2w"
auto Echo
RS422
RS232
RS422 is a Full-Duplex mode by definition, RS485 may be used in Half- or Full-Duplex. Half-
Duplex is also known as "2 wire" and denoted as "2w" here, while "4w" specifies the "4 wire"
Full-Duplex mode. Since in Half-Duplex the wires to transmit and receive data are the same, it is
June 2009
USB 2.0
Connector
1, 2, 4, 8
RS232
RS422 / RS485
RS485
3.0 Mbit/s
500 kbit/s
Data bits
Parity
Stop bits
128 Bytes
Data
Mode
Power
Table 1: Features of VScom USB-COM PRO Series
Comment
Full-Duplex, Transmitter controlled by RTS signal
Half-Duplex, Transmitter controlled by RTS signal,
sent data is suppressed
Half-Duplex, Transmitter controlled by RTS signal,
sent data is received
Full-Duplex, Transmitter activates automatic
Half-Duplex, Transmitter activates automatic, sent
data is suppressed
Half-Duplex, Transmitter activates automatic, sent
data is received
Table 2: Serial Port Operation Modes
USB-COM PRO User Manual
Full Speed or High Speed
Type B
RS232 / RS422 / RS485
RxD, TxD, RTS, CTS, DTR, DSR, DCD, RI, GND
Tx , Rx , GND
Data
RS422 and RS485
RS232
7, 8
None, Odd, Even, Mark, Space
1, 2
At least, for Transmit and Receive each
Transmit and Receive
3-Color LED
Red LED
LED
Orange
Orange
Orange
Orange
Orange
Orange
Green
Red
6