Floating-Point Data Handling (Modbus Slave) - ProSoft MVI56E-MCMR User Manual

Configuring the MVI56E-MCMR Module
User Manual
Value
Float offset
Internal Slave ID
Minimum Response Delay
Bit Input Offset
Word Input Offset
Output Offset
Holding Register Offset
Use Guard Band Timer
Guard Band Timeout

2.4.4 Floating-Point Data Handling (Modbus Slave)

In most applications, the use of floating-point data requires no special handling.
1 Copy the data to and from the MVI56E-MCMR module with a tag configured
as a data type REAL in the ControlLogix processor.
Each floating-point value will occupy 2 registers on the Modbus network.
Some Master devices use Enron or Daniel Float data. These types of floats
require one Modbus register for each float in the module memory. If your
Master requires this addressing, refer to the following section.
For standard floating-point data handling, the following is an example of
copying 10 floats to the module.
2 First, configure a tag within the ControlLogix processor.
3 Then configure a COP statement within the main routine to copy this tag to
the module's MCMR.DATA.W
The length of the copy statement is determined by the Dest file size. To copy 10
floats from the MCM_Write_Floats array to the MCMR.DATA.W
the length of the COP statement must be set to a value of 20.
To copy data from the MVI56E-MCMR module to a floating-point tag within the
ControlLogix processor
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Modbus Communication Module with Reduced Data Block
Description
Internal address for floats
Valid values are 1 to 247
0 to 65535 milliseconds to delay before response
Defines the starting address within the module for 1x Modbus
addressing. A value of 0 sets 10001 to 10016 as address 0 in the
MVI56E-MCMR module.
Defines the starting address within the module memory for 3x
registers.
Defines the starting address within the module for 0x coils.
Defines the starting address within the module for 4x addressing.
Y or N
ES O
Packet gap timeout for messages
0 to 65535
A value of 0 uses the default baud rate, or you can set a timeout value
in milliseconds.
D array.
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MVI56E-MCMR ♦ ControlLogix Platform
D array,
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