©Sealevel Systems, Inc.
SL9249 – 12/2013
7802e Manual
15
Technical Description
The COMM+8.422.PCIe provides eight RS-422/485 ports from a single PCIe slot.
The COMM+8.422.PCIe utilizes the OXPCIe954 UART. This chip features programmable baud
rates, data format, interrupt control and industry leading 128-byte transmit and receive FIFOs.
The UARTs are register compatible with 16C450, 16C550, 16C654 and 16C750 UARTs. The
FIFO depth can be changed to match the depth of these UARTs.
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
