VFD-B Series
DELTA ELECTRONICS, INC. ALL RIGHTS RESERVED
5-56
( 7.N.2)
( 7.E.1)
Start
bit
0123456
Stop
bit
10-bit character frame
( 7.O.1)
Odd
parity
Start
bit
0
12
3456
Stop
bit
10-bit character frame
Even
parity
Start
bit
01234
5
6
Stop
bit
7-bit character
10-bit character frame
Stop
bit
7-bit character
7-bit character
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
arity
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. Communication Protocol
3.1 Communication Data Frame:
ASCII mode:
STX Start character ‘:’ (3AH)
ADR 1
ADR 0
Communication address:
8-bit address consists of 2 ASCII codes
CMD 1
CMD 0
Command code:
8-bit command consists of 2 ASCII codes
DATA (n-1)
to
DATA 0
Contents of data:
n×8-bit data consist of 2n ASCII codes.
n<=25, maximum of 50 ASCII codes
LRC CHK 1
LRC CHK 0
LRC check sum:
8-bit check sum consists of 2 ASCII codes
END 1
END 0
End characters:
END1= CR (0DH), END0= LF(0AH)
RTU mode: