ABB C100 - 5 MODBUS FUNCTIONS; 5.6 Write Multiple Registers - Function Code 16; 5.6.1 Write Multiple Registers Query; 5.6.2 Write Multiple Registers Response

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…5 MODBUS FUNCTIONS
5.6 Write Multiple Registers – Function Code 16
5.6.1 Write Multiple Registers Query
This message is used to change the contents of up to eight holding registers at a
time. When used with slave address zero (broadcast mode) all slave controllers
load the selected registers with the contents specified.
Note. To write to a register, its offset address (one less than the register
number) must be used, e.g. to write to register 25, the offset address 24 (18H)
is transmitted.
Example. Write the value 500 to the register address 25 (proportional band 1 –
heat) and the value 100 to the register address 26 (integral action time) in slave 01.
Register Register Number of Byte
Address Function Start Start Registers Count
Offset High Offset Low
01 10 00 18 00 02 04
Holding Holding Holding Holding Error Check
Register 24 Register 24 Register 25 Register 25 Field (CRC16)
High Low High Low
01 F4 00 64 B2 E0
5.6.2 Write Multiple Registers Response
The Write Multiple Registers Response confirms slave identification, function code,
starting register address and quantity only.
Example
Register Register Number of Error
Address Function Start Offset Start Offset Registers Check (CRC-16)
High Low Field
01 10 00 18 00 02 C1 CF