Omron E5EK, User Manual

Page: 148 / 203

CHAPTER 6 USING THE COMMUNICATIONS FUNCTION
E5EK
6--6
•
End code
Sets the communication results. For details on the types and mean-
ings of end codes, see 6.5 How to Read Communications Error In-
formation (page 6-12).
•
FCS (Frame Check Sequence)
Set the frame check results from the start character to the data area.
For details on the frame check, see 6.6 Program Example (page 6-14).
•
“*” “CR (Carriage Return) code”
Indicates the end (terminator) of the command or response block.
F
Conversion to ASCII code at each digit of the calculation result and setting to FCS
Calculate the exclusive OR from the start character to the data section. The fol-
lowing describes an example of how to calculate the FCS for “@001000000”.
How to Calculate
FCS
(1) Convert the ASCII codes of each character to Hexadecimal “40H, 30H, ...,
30H”.
(2) Calculate the exclusive OR of all characters.
(3) Convert to ASCII code. (
→
“4B”)
(4) Set the result as FCS.
F
ASCII
→
Hex
ASCII @ 0 0 1 0 0 0 0 0 0
Hex 40H 30H 30H 31H 30H 30H 30H 30H 30H 30H
F
Completed frame (with appended terminator)
F
Exclusive OR
ASCII @ 0 0 1 0 0 0 0 0 0 7 1
Hex 40H 30H 30H 31H 30H 30H 30H 30H 30H 30H 37H 31H
ASCII @ 0 0 1 0 0 0 0 0 0 7 1 * CR
Hex 40H 30H 30H 31H 30H 30H 30H 30H 30H 30H 37H 31H 2AH 0DH
FCS
FCS Terminator
40H
¨
30H
¨
30H
¨
31H
¨
30H
¨
30H
¨
30H
¨
30H
¨
30H
¨
30H
¨
=71H