Omron SYSDRIVE 3G3JV, Руководство по связи

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Chapter 2
2-3
CompoWay/F Communications Procedures
■
BCC Calculation Example
The BCC (Block Check Character) is determined by calculating the exclusive OR of the bytes from
the node number through ETX. The 8-bit result is written to the BCC byte at the end of the frame.
■
Communications Data
Communications
protocol
Set values Negative
values
Data
Compoway/F 8-digit hexadecimal 2's comple-
ment
The decimal point is removed and the result is con-
verted to hexadecimal.
Example conversion: 105.0
→
1050
→
H'0000041A
STX Node number Sub-address SID
Command text
ETX BCC
The result of the calculation (H'35) is written to the BCC byte.
The + symbols indicate exclusive OR operations.
H'02 0 (H'30) 0 (H'30) 0 (H'30) 0 (H'30) 0 (H'30) 0 (H'30) 5 (H'35)
0 (H'30) 3 (H'33)
H'03 H'35
BCC = H'30 + H'30 + H'30 + H'30 + H'30 + H'30 + H'35 + H'30 + H'33 + H'03 = H'35