Instruction Manual
8
Application Wiring
RS-485 (Transmitter is controlled by ATTA
TM
Hardware)
TXD+ (485)
TXD- (485)
DATA (+)
DATA (-)
2-wire twisted pair cable
Please note that PCI2S485 supports optional auto echo mode operation. When enabled,
data sent to the connected RS-485 transmitter is simultaneously sent to the receiver.
The current application can then use the “echoed” data to check for data collisions.
RS-422 (Transmitter buffer always enabled)
TXD+
TXD-
RXD- (485)
TX+
RX+
TX-
RXD+ (485)
RX-
4-wire twisted pair cable
Please note that PCI2S485 supports 4-wire RS-422 mode, which requires cross-over
twisted pair cable.
PCI2S485 also provides two handshaking signals, RTS+/RTS- and CTS+/CTS- to
perform hardware flow control, which requires the following wiring scheme:
PCI2S485
RS-422 Device
