Azbil F4Q, Руководство пользователя

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5-9
Chapter 5. Modbus Communication (RTU Mode)
„
Function 16 (multiple data write command)
Function 16 is the command for writing multiple data records.
The command and normal response formats are shown in the table.
Note
•
„ Error termination code (p. 5-4) (for details of error response)
z Send command format
Frame structure Number of
bytes
Description
Address 1 Device address
Function 1 16 (0x10)
Data Data address 2 Data address (upper byte
→
lower
byte)
Number of data
records 2 Number of data records to write
(upper byte
→
lower byte)
Data size 1 Number of data bytes to write
(= 2 × number of data records)
1st data record 2 Data to write (upper byte
→
lower
byte)
to (more write data)
nth data record 2
Data to write (upper byte
→
lower
byte)
CRC check 2 Check code (lower byte
→
upper
byte)
z
Normal response format
Frame structure Number of
bytes
Description
Address 1 Device address
Function 1 16 (0x10)
Data Data address 2
Data address (upper byte
→
lower
byte)
Number of data
records 2 Number of data records to write
(upper byte
→
lower byte)
CRC check 2
Check code (lower byte
→
upper
byte)
Examples:
Sent message: Write 2 data records (1 and 2) in order, starting at data address 2001
(0x07D1)
Device
address
Function code Data address Number
of data
records
Data size Data 1 Data 2 CRC
01H 10H 07H D1H 00H 02H 04H 00H 01H 00H 02H D5H 47H