Omega RS-232 - Manual (Page 9)

Technical Description
OMG-USB-232-1 Page 6
Technical Description
The OMG-USB-232-1 utilizes a USB UART. This chip features programmable
baud rate, data format, 128 byte Dual Port TX Buffer, and 384 byte Dual Port RX
Buffer. The RS-232 transceiver supports data rates up to 460.8K baud. Refer to
Appendix C for cable length limitations.
Features
•
Hot-Pluggable device that doesn’t require opening the case
•
No system resources are required (i.e. I/O ports or IRQ’s)
•
LED status indicators for “USB Enabled”, “TD”, and “RD”
Connector Pin Assignments (DB25 Male)
Name Pin # Mode
TD Transmit Data 2 Output
RTS Request To Send 4 Output
DTR Data Term Ready 20 Output
GND Ground 7
RD Receive Data 3 Input
DCD Data Carrier Detect 8 Input
DSR Data Set Ready 6 Input
CTS Clear To Send 5 Input
RI Ring Indicator 22 Input
Note: These assignments meet EIA/TIA/ANSI-574 DTE specifications for DB-25
type connectors.