ProSoft MVI56E-MCMR User Manual page 63

MVI56E-MCMR ♦ ControlLogix Platform
Modbus Communication Module with Reduced Data Block
Parameter
Enable = YES
Internal Address = 1000
Reg Count = 10
Node Address = 1
Modbus Function =3
MB Address in Device = 0
Read Input Registers 3xxxxx (Modbus Function Code 4)
Like the 4x holding registers, 3x input registers are used for reading analog
values that are 16-bit register values. You can also use these registers to store
floating-point data (page 71). Unlike the 4x registers, 3x registers are Read Only.
The following illustration shows a sample command to read Modbus addresses
30021 to 30030 of Modbus Slave Device Address 1.
ProSoft Technology, Inc.
Description
The module will send the command every time it goes through the
command list.
Begins placing the data read from the slave device into the module at
address 1000. Internal Address 1000 of the module memory will be
copied into the tag MCMR.DATA.R
MCMR.CONFIG.ReadStartReg = 1000.
Read 10 consecutive registers from the Slave device.
Issues the Modbus command to Modbus Slave Device Address 1.
Issues Modbus Function Code 3 to Read Holding Registers.
Using Function Code 3, MB Address in Device of 0 will read Holding
Register address 40001 (or 400001, if using 6-digit addressing)
With a count of 10, this command reads 40001 to 40010 (400001 to
400010).
Configuring the MVI56E-MCMR Module
D [0], assuming
EAD ATA
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