LS Industrial Systems GLOFA G7M-DR20U, Руководство пользователя

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Chapter 8. Communication Functions
8-46
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BCC setting: set BCC when it is needed.
Item Contents
Data Type
ASCII adds 2 bytes BCC value in ASCII type to frame. Hex adds 1 byte BCC value in Hex type to
frame. For the detailed setting BCC, refer to 8.1.6 “Execution of Commands”.
Default
It is that sum all the data from 2
nd
data to the data before the data marked as [BCC] and input the
result to the [BCC] area
LRC/CRC
Set as LRC/CRC check which is provided in modbus protocol.
For ASC communication set LRC, for HEX communication set CRC.
SUM 1 BCC method uses sum like defaults, but the user can set the BCC area.
SUM 2
BCC method is the same with SUM 1, but it’s used when the user masks any value to the last BCC
value.
XOR 1 BCC method is OR (Exclusive OR).
XOR 2
BCC method is the same with XOR 1, but it’s used when the user masks any value to the last BCC
value.
MUL 1 BCC method is MULTIPLY that is, multiplication.
Check Rule
MUL 2
BCC method is the same with MUL 1, but it’s used when the user masks any value to the last BCC
value.
Range
H signifies header, S is for segment, and T is for tail.
Ex1) When header is set as [ENQ][STX], tail is set as [EOT][ETX], and the range of setting
BCC is to be from [STX] to [ETX], then set as H [1]~T [1].
Complement
It is to set whether not to take complement number or to take the complement number of 1 or 2 at
[BCC] value. If mask setting is done after taking a complement number, the user can set any value to
do masking.
Mask
Sets any value and method of masking.
Ex1) When masking by XOR method, using a value, HFF : ^FF
Ex2) When masking by OR method, using a value, HFF : |FF
Ex3) When masking by AND method, using a value, HFF : &FF