StepperOnline CLRS Series - 4.2.1 Read Holding Registers FC= 03

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CLRS Series RS485 Closed Loop Stepper Drive User Manual
4.2.1 Read Holding Registers FC= 03
Example A: Read the value of a single register--peak current
Send message: 01 03 01 91 00 01 D3 1B
Receive message: 01 03 02 00 0A 38 43
Details as following: Master->slave data:
Slave->master data:
Message:
01
03
02
00 0A
38 43
Description:
Slave ID
FC
Number of bytes returned
Value of 0x01 91
CRC
Note: 0x0191-- output peak current, 000A(Hexadecimal)=10(decimal, unit: 0.1A), it means the current 1A.
Example B: Read multiple register values
Send message: 01 03 01 BC 00 06 05 D0
Receive message: 01 03 0C 00 00 00 02 00 00 00 01 00 00 00 04 B6 13
Details as following: Master->slave data:
Message
01
03
01 BC
00 06
05 D0
Description
Slave ID
FC
Register address
Number of registers read
CRC
Slave>master data:
Message
01
03
0C
00 00
00 02
00 00
00 01
00 00
00 04
9D
B3
Description
Slave
ID
FC
Number of
bytes
returned
Value of
0x01BC
Address
0x01BD
Value of
0x01BE
Value of
0x01BF
Value of
0x01C0
Value of
0x01C1
CRC
Read Holding Registers Query (Master to
Slave)
Read Holding Registers Response (Slave to Master)
Slave ID
00 - 1F
Slaver ID
00 - 1F
FC
03
FC
03
Address of beginning register
to be read
High
Number of data bytes in
message
High
Low
Low
Total number of registers to
be read
High
Data from registers (2 bytes
per register)
High
Low
Low
CRC
Low
CRC
Low
High
High
Message:
01
03
01 91
00 01
D3 1B
Description:
Slave ID
FC
Register address
Number of registers
read
CRC