Delta Electronics VFD-M manual RTU mode

Chapter 4 Parameters

RTU mode:

START	A silent interval of more than 10 ms
ADR	Communication address: 8-bit address
CMD	Command code: 8-bit command
DATA (n-1)
	Contents of data: n×8-bit data, n<=25
…….
DATA 0
CRC CHK Low	CRC check sum:
CRC CHK High	16-bit check sum consists of 2 8-bit characters
END	A silent interval of more than 10 ms

3.3ADR (Communication Address)

Valid communication addresses are in the range of 0 to 254. An address equals to 0 means a broadcast to all AC drives (AMD) in the network. In this case, the AMD will not reply to the master device.

For example, communication to AMD with address 16 decimal: ASCII mode: (ADR 1, ADR 0)=’1’,’0’ => ‘1’=31H, ‘0’=30H RTU mode: (ADR)=10H

3.4Function (Function code) and DATA (data characters)

The format of data characters depends on the function code. The available function codes are described as follows:

03H: read data from register

06H: write single data to register

10H: write multiple data to registers

4-62 Revision May 2008, ME14, SW V3.04