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from the Automation department...
Analog values in Modbus protocol
Sensors topic
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Posted by jinson on 3 July, 2008 - 12:28 am
How to calculate the actual analog input value in Modbus protocol?
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Posted by Romulo Rodriguez on 5 July, 2008 - 11:00 am
You have to convert the byte array of the reply from the plc to an analog number. Make sure the number the plc is sending is an integer value or a real floating point value. If what you get is a floating point value it seems that you have to use the IEEE 754-1985 algorithm to make the conversion. Google it or take a look on what the wikipedia says:

http://en.wikipedia.org/wiki/IEEE_754
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