The Wiegand protocol is set at the reader level through the 1st three dipswitches on the bank of eight, on the mainboard. Out of the box, the reader is set to output Wiegand 26 with the Facility Code of 10. Below is each output setting choices and if changes are made to the dipswitches, a power cycle is needed to have the changes to take effect.

page 4 of the P85 Firmware Guide.

Standard Output Configurations.

Wiegand 26 (H10301)

Wiegand 26 is the industry standard format. It consists of a leading parity but, 8 facility code bits, 16 bits identification number and a trailing parity bit.
The facility code and id-number are transmitted with the most significant bit first. The total number of bits is 1+8+16+1=26.
The leading parity bit is even calculated over the succeeding 12 bits. The trailing parity bit is odd calculated over preceding 12 bits.

Wiegand 37 (AWF = H10302) no Facility Code

(default setting when changed to Wiegand 37)
Wiegand 26 is the industry standard format. It consists of a leading parity but, 8 facility code bits, 16 bits identification number and a trailing parity bit.
The facility code and id-number are transmitted with the most significant bit first. The total number of bits is 1+8+16+1=26.
The leading parity bit is even calculated over the succeeding 12 bits. The trailing parity bit is odd calculated over preceding 12 bits.

Wiegand 37 (AWF = H10304)

Wiegand 37 with facility code differs only from Wiegand 37 in that it has a facility code. The Wiegand 37 bit with facility code format contains 16
facility code bits and 19 bits identification number.

Additional communication protocol structures found in: