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6.4 MODBUS Common function codes
6.4.1 Read holding register command 0x03
Host -> Slave Data
Device
Function Register
Number of
address
code
address
registers
read
CRC check
01
03
00
00
00
01
85
0A
Slave -> Host Data
Device
address
Function
code
Number of
bytes
returned
Register
count
CRC check
01
03
02
0A
8C
BF
41
The return current value of the slave (register address 00) is 2700mA.
6.4.2 Write single register command 0x06
Host -> Slave Data
Device
address
Function
code
Register
address
Write data
CRC check
01
06
00
40
06
40
8A
4E
Slave -> Host Data
Device
address
Function
code
Register
address
Write data
CRC check
01
06
00
40
06
40
8A
4E
Write 1600 pulse/s to the lower 16bit of the slave speed (register address 64).