ATC Mini Chiller - ModBUS Communication Protocol
ATC MINI Chiller Modbus Protocol v1 - 03 May 2019
6
Function Code 16 is used by the master to write data to multiple sequential registers in the slave.
Master request
Slave reply
Data
Byte (Hex)
Data
Byte (Hex)
Slave address (1-254)
1
Slave address (1-254)
1
Function code ( 16 )
1
Function code (16 )
1
First register address (MSB)
1
First register address (MSB)
1
First register address (LSB)
1
First register address (LSB)
1
Number of requested registers (MSB)
1
Number of written registers (MSB)
1
Number of requested registers (LSB)
1
Number of written registers (LSB)
1
Byte count
1
CRC-16 (LSB)
1
Values
n
CRC-16 (MSB)
1
CRC-16 (LSB)
1
CRC-16 (MSB)
1
Example:The master unit requires to the slave 1 to write in the registers 10314 (0x284A) and 10315 (0x284B) the
values 100 (0x64) and 200 (oxC8)
Master request
Slave reply
Data
Byte (Hex)
Data
Byte (Hex)
Slave address
01
Slave address
01
Function code ( 16 )
10
Function code ( 16 )
10
First register address (MSB)
28
First register address (MSB)
28
First register address (LSB)
4A
First register address (LSB)
4A
Number of requested registers (MSB) 00
Number of written registers (MSB)
00
Number of requested registers (LSB)
02
Number of written registers (LSB)
02
Byte count
4
CRC-16 (LSB)
69
Value 1 (MSB)
00
CRC-16 (MSB)
BE
Value 1 (LSB)
64
Value 2 (MSB)
00
Value 2 ((LSB)
C8
CRC-16 (LSB)
C9
CRC-16 (MSB)
A8
Annex L-11M 190503 SA00011M RS485 ModBUS RTU for Mini
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