DIGITAL-LOGIC MICROSPACE MSMX104 Technical User's Manual page 23

DIGITAL-LOGIC AG
7.2 RS485 Output
The Pin 1+2 of the RS422/RS485 connector must be connected to the host bus and to the Pins 3 + 4 of
the receiver input. The Pin 1 is the TX+ and must be connected to the RX+ (Pin 3) and the A-signal of
the RS485 bus of the host. The Pin 2 is the TX- and must be connected to the RX- (Pin 4) and the B-
signal of the host computer.
Only the receiver inputs of the MICROSPACE interface card MSMX104 is terminated with 100Ohms.
RX+
RX-
TX+
TX-
ADM489
470Ohm
100Ohm
470Ohm
23
MSMX104 Manual V1.3
Signal-A
RS486 bus
to / from host
Signal-B