Velleman HAA2866 - Manual (Page 34)

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THE 34 BIT WIEGAND DATA OUTPUT FROM THE ENTRY OF USER PINS
Wiegand is also a commonly used interface between keypad with user PINs and control panels used
in access control. The keypad unit is designed to accept both card reading and PIN code entry in
operation without conflict to the two media and confusion to the control panel. It accepts User PINs
up to 8 digits maximum in decimal numbers. The Wiegand data protocol has been expended to 34
bits to accommodate the maximum PIN length without causing code error (26 bits Wiegand data for
PIN causes error to number 16,777,215 or any number above 16,777,215). The 34 bit and the 26 bit
Wiegand signals are transmitted in the same electrical manner and timing standard in Binary Codes.
The 34 bit Wiegand protocol for PINs has 1 first parity bit, 32 bits for the PIN code, and 1 stop bit for a
total of 34 bits. The first parity bit is an Even parity bit calculated from the first 16 bits of the code and
the trailing parity bit is an Odd parity bit from the last 16 bits.
Example 2 : Wiegand Output from PIN / Code Entry
A) The keyed-in PIN is 1 2 3 4 5 6 7 8
The PIN in Decimal Number : 1 2 3 4 5 6 7 8
The PIN 1 2 3 4 5 6 7 8 Equivalent to Hex Number : B C 6 1 4 E
E 0 0 B C 6 1 4 E O
An Even Parity Bit of 0 0 B C = 1 An Odd Parity Bit of 6 1 4 E = 0
The 34 bits Wiegand data sending out in Binary from entry of the PIN:
1 0 0 0 0 0 0 0 0 1 0 1 1 1 1 0 0 0 1 1 0 0 0 0 1 0 1 0 0 1 1 1 0 0
B) The keyed-in PIN is 1 2 3 4
The PIN in Decimal Number : 1 2 3 4
The PIN 1 2 3 4 Equivalent to Hex Number : 4 D 2
E 0 0 0 0 0 4 D 2 O
An Even Parity Bit of 0 0 0 0 = 0 An Odd Parity Bit of 0 4 D 2 = 0
The 34 bits Wiegand data sending out in Binary from entry of the PIN:
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 1 1 0 1 0 0 1 0 0
C) The keyed-in PIN is 0 0 0 0 1 2 3 4
The PIN in Decimal Number : 0 0 0 0 1 2 3 4
The PIN 0 0 0 0 1 2 3 4 Equivalent to Hex Number : 4 D 2
E 0 0 0 0 0 4 D 2 O
An Even Parity Bit of 0 0 0 0 = 0 An Odd Parity Bit of 0 4 D 2 = 0
The 34 bits Wiegand data sending out in Binary from entry of the PIN:
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 1 1 0 1 0 0 1 0 0
Important Note:
a)
b)
From the above examples (B) & (C), The PINs 1 2 3 4 and 0 0 0 0 1 2 3 4 give the same Wiegand
data output in Binary.
Pressing any number of only 0’s prior to the PIN makes error code in Binary. Do NOT program the
PIN with 0’s in front of it.