Delta Electronics ASDA-B2 series User Manual page 275

Chapter 8 MODBUS Communications
11-bit character frame (For 8-bit character)
8N2
Start
0
bit
8E1
Start
0
bit
8O1
Start
0
bit
 Communication Protocol:
ASCII Mode:
Start
Slave address
Function
DATA(n-1)
.......
DATA(0)
LRC
End 1
End 0
ASCII Mode: ':' character
ADR (Communication Address) consists of 2 ASCII codes and it ends in CR (Carriage Return) and
LF (Line Feed)
CR (Carriage Return) is represented by ASCII number 13, and LF (Line Feed) is represented by
ASCII number 10.
There are communication address, function code, contents of data, LRC (Longitudinal Redundancy
Check) between start and end characters.
8-8
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Manuel Baliña 456, Lomas de Zamora (B1832CCJ) Buenos Aires, Argentina.
VARITEL INGENIERIA ELECTRONICA S.A.
1 2 3
8-data bits
11-bits character frame
1 3
2
8-data bits
11-bits character frame
1 2 3
8-data bits
11-bits character frame
Start character': ' (3AH)
Communication address: 1-byte consists of 2 ASCII codes
Function code: 1-byte consists of 2 ASCII codes
Contents of data: n word = n x 2-byte consists of n x 4 ASCII codes,
n10
LRC check sum: 1-byte consists of 2 ASCII codes
End code 1: (0DH)(CR)
End code 0: (0AH)(LF)
4 5 6
7
4 5 6
7
4 5 6
7
ASDA-B2
Stop
Stop
bit
bit
Even
Stop
parity
bit
Odd
Stop
parity
bit
Revision September 2013