User's Manual

HF Mifare Easy Module V1.0
ACG Identification Technologies GmbH 25
7.2.4 Data
This part contains the command and data. The command values are the same as in
ASCII protocol mode (‘x’, ‘s’, …) whereas data is transmitted binary.
The length of the command block depends on the instruction.
7.2.5 Block Check Character (BCC)
The BCC is used to detect transmission errors. The BCC is calculated XOR-ing each
byte of the transmission frame excluding the STX/BCC and ETX character.
)(...)()()(
0 N
DataXORXORDataXORLengthXORStatIDBCC =
7.2.6 ETX
End of transmission. (03h)
7.2.7 Remarks
If the reader device receives an invalid instruction frame (i.e. BCC wrong) or the
requested station ID does not match the internal ID of the reader, the command is
not executed. The reader waits for the next valid frame.
The automatic binary timeout (see protocol configuration register) is used to detect
incomplete binary frames.
The reader module answers in the same telegram format, with the ID-field set to 0.
The Data block of the answers in binary protocol mode does match the ASCII mode
answers, with the only difference that data values are transmitted binary instead of
ASCII Hex.