Delta DVP-EX2

4. Communications
4-13
4.5 Command Code
4.5.1 Command Code: 01, Read Status of Contact (Input point X is not included)
Number of Points (max) = 255 (Dec) = FF (Hex)
Example：Read contacts T20~T56 from Slave ID#1
PC→PLC “:01 01 06 14 00 25 BF CR LF”
Sent message:
Field Name
ASCII
STX
:
Slave Address
01
Command code
01
Starting Address Hi
06
Starting Address Lo
14
Number of Points Hi
00
Number of Points Lo
25
Error Check (LRC)
BF
ETX 1
0D (Hex)
ETX 0
0A (Hex)
Assume Number of Points in sent message is n (Dec), quotient of n/8 is M and the remainder is N.
When N = 0, Bytes Count in feedback message will be M; when N≠0, Bytes Count will be M+1.
PLC→PC “:01 01 05 CD 6B B2 0E 1B D6 CR LF”
Feedback message:
Field Name
ASCII
STX
:
Slave Address
01
Command code
01
Bytes Count
05
Data (Coils T27…T20)
CD
Data (Coils T35…T38)
6B
Data (Coils T43…T36)
B2
Data (Coils T51…T44)
0E
Data (Coils T56…T52)
1B
Error Check (LRC)
E6
END 1
0D (Hex)
END 0
0A (Hex)