I have set it up as a digital input.I think I have sold the issue but it still seems a little weird.Let me explain...First of all one wire to physical pin 19 (probe input) and the other wire at Ground without a pullup resistor as my board is V1.4.Then in pokeys plugin through Mach3 I set the input 19 as probe input in Pulse Engine Settings tab and also in PokeysMapping tab.The weird thing is in Diagnostics tab of mach 3 the Digitize Led blinks randomly without doing nothing but the probe works.If I go to pulse engine tab and put none in probe input but let the pin 19 as probe in Pokeyw Mapping tab then in diagnostics the led works fine,on when I touch the two wires off when they dont touch,but the Probe doesnt work,mach3 shows a message "No probe input".