Technical
OMG-USB-SER-2
Page
8
Technical Description
The
OMG-USB-SER-2
utilizes two USB UARTs. These chips feature
programmable baud rate, data format, 128 byte Dual Port TX Buffer, and 384 byte
Dual Port RX Buffer. The RS-232/422/485 transceiver supports data rates up to
921.6K baud for RS-422/485 and up to 460.8K baud for RS-232.
Features
•
Hot pluggable device that does not require opening the case
•
No system resources are required (i.e. I/O ports or IRQ’s)
•
LED status indicators for USB Enabled and port activity
Connector Pin Assignments
RS-422/485 (DB 9 Male)
Signal
Name
Pin #
Mode
GND
Ground
5
TX +
Transmit Data Positive
4
Output
TX-
Transmit Data Negative
3
Output
RTS+
Request To Send Positive
6
Output
RTS-
Request To Send Negative
7
Output
RX+
Receive Data Positive
1
Input
RX-
Receive Data Negative
2
Input
CTS+
Clear To Send Positive
9
Input
CTS-
Clear To Send Negative
8
Input
RS-232
(DB-9 Male)
Signal
Name
Pin #
Mode
GND
Ground
5
TX
Transmit Data
3
Output
RTS
Request To Send
7
Output
DTR
Data Terminal Ready
4
Output
RX
Receive Data
2
Input
CTS
Clear To Send
8
Input
DSR
Data Set Ready
6
Input
DCD
Data Carrier Detect
1
Input
RI
Ring Indicator
9
Input
