RKC INSTRUMENT PG500, Инструкция по эксплуатации системы связи

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4. MODBUS COMMUNICATION PROTOCOL
IMR02F04-E1
37
4.6.4 Preset multiple registers [10H]
The query message specifies the starting register address and quantity of registers to be written.
The write data is arranged in the query message with high-order 8-bit first and low-order 8-bit next. Only
R/W holding registers can be specified.
Example: Data is written into the two holding registers from 00F4H [Alarm 1 set value] to 00F5H
[Alarm 2 set value] of slave address 1.
Query message
Slave address 01H
Function code 10H
Starting number High 00H
Low F4H
Quantity High 00H
Low 02H
Number of data 04H
Data to first register High 00H
(Low-order word)
Low
32H
Data to next register High 00H
(High-order word)
Low
32H
CRC-16 High DDH
Low 02H
Normal response message
Slave address 01H
Function code 10H
Starting number High 00H
Low
F4H
Quantity High 00H
Low 02H
CRC-16 High 00H
Low 3AH
Error response message
Slave address 01H
80H

Function code
90H
Error code 02H
CRC-16 High CDH
Low C1H
First holding register address
The setting must be between 1 (0001H) and
123 (007BH).
Number of holding registers

2
Any pertinent data