reading a 32bit value from a modbus slave device using com_mod_mast
I want to read a float value from a mod bus slave device using com_mod_mast.
Is any type casting required to read the value properly in plc, if so then how to do it.
i have defined an array of datatype word of length 2 in the data input of the com_mod_mast block.But Im getting some unknown value of 16828 in the first word of the array while the second word reads zero for a value of 23.5 in the slave device.
Asked 2 years ago
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No type cast required. Just change your array to real type variable. If the value is still incorrect then you probably have reversed bytes or words
Answered 2 years ago
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Hello,
You can refer Codesys help file for information on COM_MOD_MAST block.
You can refer Codesys help file for information on COM_MOD_MAST block.
Answered 2 years ago
1
https://forum.codesys.com/viewtopic.p...
The value you are reading is an IEEE floating point number. You can verify it here ... https://www.h-schmidt.net/FloatConver...
Answered 2 years ago
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