Hitachi NJI-350B - Manual (Page 262)

Chapter 11 Communication Specifications
11-9
11.6.2 Port 2
Port 2 of the MICRO-EH is a communication port that uses either the RS-422 or RS-485 protocol as interface. It is also a
dedicated port with which to perform communication by the H series dedicated procedure (high protocol), which allows
1:n station communication. Figure 11.6 and 11.7 show examples of port 2 connections for 1:n station communication.
Moreover, the connection for communicating 1:1 is performed by connecting only the first CPU in the figure below.
(1) In case of RS-422
MICRO-EH
(32nd CPU)
MICRO-EH
(2nd CPU)
MICRO-EH
(1st CPU)
Host
RD (+)
RD (-)
SD (-)
SD (+)
(13) SDP
(12) SDN
(11) RDP
(10) RDN
(13) SDP
(12) SDN
(11) RDP
(10) RDN (13) SDP
(12) SDN
(11) RDP
(10) RDN
Figure 11.6 Connection for 1:n station communication by RS-422
(2) In case of RS-485
Relay terminal block Relay terminal block
Twisted pair cable
Relay terminal block
MICRO-EH
(1st CPU)
Host
RD (+)
RD (-)
SD (-)
SD (+)
B
A
MICRO-EH
(32nd CPU)
(13) SDP
(12) SDN
(11) RDP
(10) RDN
(13) SDP
(12) SDN
(11) RDP
(10) RDN
Figure 11.7 Connection for 1:n station communication by RS-485