Hitachi SJ700-2 - Manual (Page 194)

Chapter 4 Explanation of Functions
(3) How to calculate the block check code (BCC)
(Example) When using the 01 command (frequency-setting command) to set the inverter output
frequency to 5 Hz (the station No. of the inverter is 01):
Transmission fr
tation No. d a
ASCII code
ame configuration
S Comman Dat
The contents of "Station No." to "Data" are converted into ASCII data, and the ASCII data is XORed bit by
bit. The final XOR result is set as the block check code (BCC). In the above example of transmission
frame, BCC is calculated as follows:
(Refere e) ASCII code conversion ta e
Character data ASCII code Character data ASCII code
nc bl
S 41 TX 2 A
ACK 6 42 B
CR 0D C 43
NAK 15 D 44
0 30 E 45
1 31 F 46
2 32 H 48
3 33 P 50
4 34 b 62
5 35
6 36
7 37
8 38
9 39
05 (This result is used as BCC.)
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