Keri Systems BioPointe Users Manual - Manual (Page 72)

Appendix C –Communicating in RS422 and RS485
71
Appendix C
14 Appendix C – Communicating in RS422 and RS485
The following examples show how three BioPointe are connected in daisy chain using RS422 first and
RS485 next.
The following diagram shows a schematic layout of the connection. Appendix C can be referred to for a pinout
description for the RS422 or RS485 signals at the ADAM. ADAM configurations are also described in the
Appendix C. Note that terminating resistors are required at the ADAM. The contents that follow in this Appendix
will describe how the terminating resistors are connected as well as how to connect the various pin -outs.
Schematic Diagram of a netwok of BioPointe in RS422 / RS485
The following diagram shows a schematic layout of the T-Junction box. There are three main sections for the
pin-outs, namely ‘IN’, ‘OUT’ and ‘DAISY CHAIN’. Each pin number of a section is internally shorted to the
similar pin number of the other two sections. If this is the first T-Junction box from the ADAM, the RS422 or
RS485 signals go into the ‘IN’ section. The signals from the ‘OUT’ section go into the BioPointe unit. And the
signals from the ‘DAISY CHAIN’ section go into the next T-Junction box. Take note that the ‘DAISY CHAIN’
section of the last junction box has to be terminated with terminating resistors. The recommended colors of the
wires to use are also shown.
CN2
CN1
1 2 3 4 1 2 3 4