User Manual
Z-SG2 / Z-SG2-L
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Doc: MI-005370-EN
Rev. 1.0.0.2
Page 39
NUMBERING OF MODBUS ADDRESSES WITH "0-BASED" CONVENTION
The numbering is:
HOLDING REGISTER MODBUS
ADDRESS (OFFSET)
MEANING
0
FIRST REGISTER
1
SECOND REGISTER
2
THIRD REGISTER
3
FOURTH REGISTER
4
FIFTH REGISTER
Therefore the first register is at address 0.
In the following tables, this convention is indicated with “ADDRESS OFFSET”.
NUMBERING OF MODBUS ADDRESSES WITH "1 BASED" CONVENTION (STANDARD)
The numbering is that established by the Modbus consortium and is of the type:
HOLDING REGISTER MODBUS
ADDRESS 4x
MEANING
40001
FIRST REGISTER
40002
SECOND REGISTER
40003
THIRD REGISTER
40004
FOURTH REGISTER
40005
FIFTH REGISTER
In the following tables this convention is indicated with “ADDRESS 4x” since a 4 is added to the address so
that the first Modbus register is 40001.
A further convention is also possible where the number 4 is omitted in front of the register address:
HOLDING MODBUS ADDRESS
WITHOUT 4x
MEANING
1
FIRST REGISTER
2
SECOND REGISTER
3
THIRD REGISTER
4
FOURTH REGISTER
5
FIFTH REGISTER
