Technical Description
Sealevel Systems
COMM+4.PCI
Page
7
Technical Description
The Sealevel Systems
COMM+4.PCI
provides a PCI interface adapter with 4
RS-232/422/485 asynchronous serial ports for industrial automation and control
applications.
The
COMM+4.PCI
utilizes the 16C864 UART. This chip features
programmable baud rates, data format, interrupt control and industry leading
128-byte transmit and receive FIFOs.
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
DB-9 RS-232 (DB-9 Male)
Signal
Name
Pin #
Mode
GND
Ground
5
TD
Transmit Data
3
Output
RTS
Request To Send
7
Output
DTR
Data Terminal Ready
4
Output
RD
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
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
ensure you get the best performance from your adapter.
