Gram ZFOC Serie Manual De Utilización página 56

BCC. Character of data verify. One byte. Set STA to D1, SIGN to D2, byte before
BCC to DN, so BCC=D1^D2^. .^DN.'^' is a logic XOR operator.
ETX. Symbol of ending data item, one byte, fixed at 03H.
EOT. Symbol of ending sending, one byte, fixed at 04H.
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