Adding A Bcc (Block Check Code); An Overview Of The Bcc; Sample Programs - Panasonic FP2 User Manual

FP2 Serial Data Unit
8.1

Sample Programs

8.1.1

Adding a BCC (block check code)

8.1.1.1

An Overview of the BCC

With serial communication, erroneous data can sometimes occur because of noise or
another factor. With the normal parity check, the data is checked to see if the total number
of "1" bytes in one data element is an even or an odd number, but the BCC (block check
code) can be used for a more sophisticated check.
FP2
SDU
SD RD ERR SD RD ERR AL
COM.1 C OM.2
COM.1(RS232C)
COM.2(RS232C)
Received data and
BCC are compared,
and contents
checked
Received data
On the sending side, this code is inserted just before the end code and the data is sent.
On the receiving side, the received data is compared with this code, and the data is
checked for reliability.
Receiving side
BCC
Sending side
BCC is added based on
contents of sent data
Data sending
Sample Programs
8.1 Sample Programs
FP1
BCC
Sent data
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