RF Ideas Inc PCPROXC101 Manual Do Utilizador

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pcProx
®
 
 
 
Card Formats Tab 
 
There are several bits constructed together 
which make up the data sent from the proximity 
token to the pcProx reader. The pcProx 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. 
 
IDENTIFICATION CODE