Omega OMG-USB-SER-2 User Manual

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 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 
 
TX + 
Transmit Data Positive 
Output  
TX- 
Transmit Data Negative 
Output  
RTS+ 
Request To Send Positive 
Output  
RTS- 
Request To Send Negative 
Output  
RX+ 
Receive Data Positive 
Input  
RX- 
Receive Data Negative 
Input  
CTS+ 
Clear To Send Positive 
Input  
CTS- 
Clear To Send Negative  
Input  
RS-232 
(DB-9 Male) 
Signal 
Name 
Pin # 
Mode 
GND 
Ground 
 
TX 
Transmit Data 
Output 
RTS 
Request To Send 
Output 
DTR 
Data Terminal Ready 
Output 
RX 
Receive Data 
Input 
CTS 
Clear To Send 
Input 
DSR 
Data Set Ready 
Input 
DCD 
Data Carrier Detect 
Input 
RI 
Ring Indicator 
Input