Appendix D:  Johnson N2 Protocol Implementation Conformance Statement
   
 
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Integration Guide    All rights reserved 
  49 
 
Vendor Name: 
 
Product Names: 
 
Product Model Number: 
 
Protocol Description: 
N2 is not a standard protocol, but one that was created by Johnson Controls, Inc. that has been made open and 
available to the public. The speed of N2 network is limited to only 9600 baud. The N2 slave address can be set 
from 01 to 99. 
Product Description: 
The RTU Open is a factory-installed rooftop controller that is capable of speaking multiple protocols. The RTU Open 
controller speaks the Johnson N2 Open Protocol as described in the Metasys N2 System Protocol Specification 
(for Vendors) document, revision 6/13/96.  Further details on the N2 supported implementation are described 
below. 
 
 
 
Appendix D:  Johnson N2 Protocol Implementation Conformance 
Statement