Moeller DF51 - Page 160

Serial interface (Modbus)
10/05 AWB8230-1541GB
156
Example:
This example writes the start signal for a frequency inverter with
slave address 10 to coil number 1.
Precondition: PNU A002 has the value 03.
Writing to holding register [06
hex
]
This function writes data to a selected holding register.
Example.
• Reference input (PNU A020). Write 50 Hz as first fixed
frequency to the frequency inverter with slave address 5.
• Frequency reference value 50 Hz is transferred in the form of
value 500 (01F4
hex
) as reference input 0 (PNU A020) to holding
register 003A
hex
. The first value is 0.1 Hz.
If the data written to the selected coil contains errors, an exception
message is issued (a page 160).
Request: Answer:
No. Name Exampl
e
No. Name Exampl
e
hex hex
1 Slave address (broadcast disabled) 0A 1 Slave address 0A
2 Function code 05 2 Function code 05
3 Coil start number (High byte) 00 3 Coil start number (High byte) 00
4 Coil start number (Low byte) 01 4 Coil start number (Low byte) 01
5 Change data (High byte) FF 5 Change data (High byte) FF
6
Change data (Low byte) 00 6 Change data (Low byte) 00
7 CRC-16 (High byte) DC 7 CRC-16 (High byte) DC
8 CRC-16 (Low byte) 81 8 CRC-16 (Low byte) 81
Request: Answer:
No. Name Exampl
e
No. Name Exampl
e
hex hex
1 Slave address (broadcast disabled) 05 1 Slave address 0A
2 Function code 06 2 Function code 05
3 Register start number (High byte) 00 3 Register start number (High byte) 00
4 Register start number (Low byte) 3 A 4 Register start number (Low byte) 3 A
5
Change data (High byte) 01 5 Change data (High byte) 01
6
Change data (Low byte) F4 6 Change data (Low byte) F4
7 CRC-16 (High byte) A8 7 CRC-16 (High byte) A8
8 CRC-16 (Low byte) 54 8 CRC-16 (Low byte) 54