Adamczewski GmbH
Manual AD-MM 500 FE
RL
Register Lowbyte
RCH
Registercount Highbyte
RCL
Registercount Lowbyte
BC
Bytecount
D0H
Dataword 0 Highbyte
D0L
Dataword 0 Lowbyte
DNH
Dataword n Highbyte
DNL
Dataword n Lowbyte
CRCL
16-Bit CRC Lowbyte
CRCH
16-Bit CRC Highbyte
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 of 2 (0x0002) to the slave. If everything is OK, the slave replies with the
number of bytes and the requested registers.
Request
SA
FC
RH
RL
RCH
RCL
CRCL
CRCH
1
0x03
0x9F
0x61
0x00
0x02
...
...
Response
SA
FC
BC
D0H, D0L, DNH, DNL
CRCL
CRCH
1
0x03
4
0x00, 0x00, 0x00, 0x00
...
...
In the event of an error, the slave responds with an error message:
Exception
Slave
Errorcode
Exception
CRC Low
CRC High
1
0x83
see 8
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 registers to
be written to the slave. If all data are OK, the slave replies with the start address and the number
of written registers. Example: the master writes a 4-byte counter (unsigned uint32) with the value
243186 (0x0003B5F2) to register 45300 (0xB0F4) of the slave with address 2.
Request
SA
FC
RH
RL
RCH
RCL
BC
D0H, D0L, ... DNH, DNL
CRCL
CRCH
2
0x10
0xB0
0xF4
0x00
0x02
0x04
0x00, 0x03, 0xB5, 0xF2
...
...
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1.0 2021-05-19