I solved my problem in this way:
Measurment of voltage on switches pins showed me 4V, and I decided to rise up this value with external 5V supply. But it still doesn't works. Signal LED was lit all time, because it's 13 pin, but 13 pin is J6dirPIN too... Once this pin wasn't initialized and I saw that LED partially lit. The reason was a voltage between GND of external 5V supply and GND of my laptop. I disconnected GND of external 5V and now endstops work.