Impulse 7205 - Manual (Page 11)

Technical Description
Sealevel Systems ULTRA COMM+2.LPCI Page 8
Technical Description
The Sealevel Systems ULTRA COMM+2.LPCI provides a Low Profile PCI interface adapter with 2 asynchronous
serial ports providing a versatile interface, field selectable as RS-232 for modems, printers and plotters, as well as
RS-422/485 for industrial automation and control applications.
The ULTRA COMM+2.LPCI utilizes the 16850 UART. This chip features programmable baud rates, data format,
interrupt control and a 128-byte input and output FIFO. The ULTRA COMM+2.LPCI also supports the Oxford
Semiconductor 16C950. This chip features the same FIFO and automatic RS-485 driver enable capabilities as the
16C850, and enhanced clocking features.
Connector Pin Assignments
RS-232
Signal Name Pin # Mode
TD Transmit Data 3 Output
RTS Request To Send 7 Output
DTR Data Term Ready 4 Output
GND Ground 5
RD Receive Data 2 Input
DCD Data Carrier Detect 1 Input
DSR Data Set Ready 6 Input
CTS Clear To Send 8 Input
RI Ring Indicator 9 Input
Note: These assignments meet EIA/TIA/ANSI-574 DTE for DB-9 type connectors.
Technical Note: Please terminate any control signals that are not going to be used. The most common way to do
this is connect RTS to CTS and RI. Also, connect DCD to DTR and DSR. Terminating these pins, if not used,
will help insure you get the best performance from your adapter.
RS-422/485
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