Adamczewski AD-MM 400, Manual

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7.5 Supported Functions
The AD-MM 400 supports the following functions as master and slave on the RS-485
interface.
3 (0x03) Read Holding Registers.
16 (0x10) Write Multiple Registers.
7.5.1 Read Holding Registers
This function is used to read one or more registers.
Example: The master sends a request with the start address 40801 (0x9F61) And a
number of registers to be read from 2 (0x0002) to the slave:
Slave Function Register
High
Register
Low Number
High Number
Low CRC
Low CRC
High
1 0x03 0x9F 0x61 0x00 0x02 ... ...
If everything is correct, the slave responds with the number of bytes and the registers
requested:
Slave Function Number
Bytes
Reg0
High Reg0
Low Reg1
High Reg1
Low CRC
Low CRC
High
1 0x03 4 0x00 0x00 0x00 0x00 ... ...
In the event of an error, the slave responds with an error message:
Slave Error Code Exception CRC0 CRC1
1 0x83 see 7.6
7.5.2 Write Multiple Registers
This function is used to write one or more registers.
The master sends a request with the start address, the number of registers and the To
be written to the slave:
Slave Func. Reg.HighReg.LowNumber
High
Number
Low Bytes Value
High Value
Low CRC
Low CRC
High
1 0x10
If all data are correct, the slave responds with the start address and the number of
written registers:
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