Delta Electronics VFD-DD Series - Page 92

Chapter 4 Parameter Settings|DD Series
4-68
11-bit character frame (For RTU):
Start
bit
0123456
Stop
bit
Stop
bit
8-bit character
11-bit character frame
( 8.N.2 )
Start
bit
01234
5
6
Even
parity
Stop
bit
11-bit character frame
( 8.E.1 )
Start
bit
01234
5
6
Stop
bit
11-bit character frame
( 8.O.1 )
Odd
parity
7
7
7
8-bit character
8-bit character
 3.1 Communication Protocol
Communication Data Frame:
ASCII mode:
STX Start character ‘:’ (3AH)
Address Hi
Address Lo
Communication address:
8-bit address consists of 2 ASCII codes
Function Hi
Function Lo
Command code:
8-bit command consists of 2 ASCII codes
DATA (n-1)
…….
DATA 0
Contents of data:
Nx8-bit data consist of 2n ASCII codes
n<=16, maximum of 32 ASCII codes
LRC CHK Hi
LRC CHK Lo
LRC check sum:
8-bit check sum consists of 2 ASCII codes
END Hi
END Lo
End characters:
END1= CR (0DH), END0= LF(0AH)
RTU mode:
START A silent interval of more than 10 ms
Address Communication address: 8-bit address
Function Command code: 8-bit command
DATA (n-1)
…….
DATA 0
Contents of data:
n×8-bit data, n<=16
CRC CHK Low
CRC CHK High
CRC check sum:
16-bit check sum consists of 2 8-bit characters
END A silent interval of more than 10 ms