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6 ] bcc for horizontal parity checking, Bcc for horizontal parity checking – Denso BHT-6000 User Manual

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[ 6 ] BCC for Horizontal Parity Checking

To check whether data has been transmitted accurately, the BHT-6000 supports hori-
zontal parity checking for every transmission block.

In horizontal parity checking, a horizontal parity byte so called BCC (Block Check
Character) is suffixed to an ETX of every transmission block.

In the BHT-protocol, every parity bit of BCC is set so that all set bits at the same bit
level (including a parity bit) in the characters contained in the transmission block have
an even number by binary addition, excluding SOH, STX, and functions SOH$ and
STX$.

(For details about SOH$ and STX$ which are protocol functions unique to BHT-BASIC
3.0, refer to the "BHT-BASIC 3.0 Programmer's Manual.")

b7

b0

Character

(Vertical parity)

Horizontal parity byte

(BCC)

[ For 8-bit data ]

Shown below is a data text block indicating the bits to be added for horizontal parity
checking.

To be added for
horizontal parity
checking

Serial
number

Data text