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© Sealevel Systems, Inc.
7105-DB9 Manual | SL9053 9/2021
Technical Description
The Sealevel Systems
ULTRA 485.OPTO22
provides an additional asynchronous serial port, field
selectable as RS-422/485 for industrial automation and control applications.
The
ULTRA 485.OPTO22
utilizes the EXAR 16C850 UART. This chip features programmable baud rates,
data format, interrupt control and industry leading 128-byte FIFOs.
Connector Assignments
RS-422/485 Pin Assignments
Signal
Name
Pin #
Mode
GND
Ground
3
RDB
RX+
Receive Positive
8
Input
RDA
RX-
Receive Negative
9
Input
CTSB
CTS+
Clear To Send Positive
6
Input
CTSA
CTS-
Clear To Send Negative
7
Input
TDB
TX+
Transmit Positive
4
Output
TDA
TX-
Transmit Negative
5
Output
RTSB
RTS+
Request To Send Positive
1
Output
RTSA
RTS-
Request To Send Negative
2
Output