RFIDeas AIR ID, Руководство пользователя

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© 1998-2005 RF IDeas, Inc.
Card Formats Tab
There are several bits constructed together
which make up the data sent from the proximity
token to the reader. The reader reads all bits for
any format card produced.
The proximity token has several bits, and these
will vary from customer to customer. There are
literally hundreds of bit formats and lengths for
proximity cards! The most popular is the 26-bit
format card. There are actually 24 bits of usable
information as the first and last bits are really
parity bits to ensure data integrity.
This is typical layout for a 26-bit card.
PARITY BIT
The leading and trailing 1-3 bits are usually the
parity bits. For a 26-bit card, only 1 leading and
1 trailing parity bit is used.