using 5v-12v as input sensor

[amararsa24s]

let "inverted: false" have a test.

i did that, it doesn't help.

the A6 have constant 12v on D3 which is feed to the output of the PNP sensor. in that case, even if the sensor is triggered, D3 will still see 12v.

i also tried setting mode to  INPUT_PULLDOWN or  INPUT_PULLUP but it's not acceptable with the pcf8574. 

(btw-how can i upload photos/wiring diagrams here?)