Example System Default Card Format HID 35bits

Total Bit Length: 35 Facility Code: 3522
Facility Code Start Bit: 3 Facility Code Length: 12
Card Number Start Bit: 15 Card Number Length: 20

This Format will only allow us to use card number from 1-1048575
Because the card number bit length is only 20bits
if you open a calculator and convert 1048575 to binary this will be the result in binary is ‭11111 11111 11111 11111

If we change the same format 
Total Bit Length: 35 Facility Code: 35
Facility Code Start Bit: 3 Facility Code Length: 7
Card Number Start Bit: 10 Card Number Length: 25
This Format will only allow us to use card number from 1-3355443
Because we increase the amount of bits for the card number section.

More to come

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