ProSoft Technology MVI69-MCM User Manual

Page 60

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Configuring the MVI69-MCM Module

MVI69-MCM ♦ CompactLogix or MicroLogix Platform

User Manual

Modbus Communication Module

Page 60 of 167

ProSoft Technology, Inc.

March 22, 2011

Floating Point Support
The movement of floating point data between the MCM module and other

devices is easily accomplished as long as the device supports IEEE 754 Floating

Point format. This IEEE format is a 32-bit single precision floating point format.
The programming necessary to move the floating point data takes advantage of

the CPS command that exists in the Compact Logix and SLC processors. The

CPS command is unique for CPX/SLC data movement commands in that it is an

untyped function, meaning that no data conversion is done when moving data

between file types (that is, it is an image copy not a value copy).
The structure of the CPS command to move data from a Floating Point file into

an integer file (something you would do to move floating point values to the

module) is as follows:

This command will move one floating point value in two 16 bit integer images to

the integer file. For multiple floating point values increase the count field by a

factor of 2 per floating point value.
The structure of the COP command to move data from an Integer file to a

Floating Point file (something you would do to receive floating point values from

the module) is as follows:

This command will move two 16 bit integer registers containing one floating point

value image to the floating point file. For multiple values increase the count field.

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