Reference MVI46-N2
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SLC Platform
Johnson Controls N2 Communication Module
ProSoft Technology, Inc.
Page 47 of 68
October 27, 2008
The following illustration shows the data transfer method used to move data
between the SLC processor, the MVI46-N2 module and the N2 network.
All data transferred between the module and the processor over the backplane is
through the M0 and M1 files. Ladder logic must be written in the SLC processor
to interface the M-file data with data defined in the user-defined data files in the
SLC. All data used by the module is stored in its internal database.
User data contained in this database is continuously read from the M1 file.
Block identification codes define specific functions to the module. The module
uses the following block numbers:
Block Range
Descriptions
9001
Write Binary Object
9002
Write Analog Output
9998
Warm-boot control block.
9999
Cold-boot control block.
Each block has a defined structure depending on the data content and the
function of the data transfer.
Normal Data Transfer
This version of the module provides for direct access to the data in the module.
All data related to the module is stored in the module's M1 file. To write data to
the module, use the COP instruction to copy data from a user file to the module's
M1 file.
