Multitek MultiLed M812-LD Series Operating Manual page 57

Function 16 (10 hex) - Preset Multiple registers (4X)
These registers contain the system settings and controls. Register
addresses in the MultiLed at 0, but in keeping with Modicon
Modbus codes, are designated addresses starting 40001.
Write
Packet from master :
[Node addr][10][Register start address(2 bytes)][No of registers(2
bytes)][Byte count][Data (byte count bytes)][CRC (2 bytes)]
Response from slave format :
[Node addr][10][Register start addr.(2 bytes)][No of
registers(2 bytes)][CRC (2 bytes)]
The table lists the parameter, its Modbus equivalent address and its
address within the MultiLed. Any Illegal operation will return an
Error code.
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