I have Wiegand 26bit bus.
- DATA0 - GND = ~12.5V when idle
- DATA1 - GND = ~12.5V when idle
I need some sort of scheme or something to convert 12V signal to 5V without interfere.
I have few thoughts:
Optocoupler. Will the R1 and LED interfere a lot?
MOSFET. What would be the scheme?
- MAX232 chip. a bit difficult at the moment to test
Please suggest something for this case.
The scheme of
EM Fields does work. But i have one more problem.
There are 2 RFID readers connected in parallel. One is newer version than the other. They are configured to give Wiegand 26bit output.
1 parity bit + 8 bit site code + 16 bit card number + 1 parity bit = 26 bit
When i tried to read i received this
Card number is 140,2193
1 10001100 0000100010010001 1, but i noticed that the older one gives extra
0(marked with red dots) after
1. That means DATA0 line is triggered to low after every
1. Security system reads card correct. What could cause the line go low?