Hi I have a problem with the ne555 timer. What I'm supposed to do is that I receive an positiv input PULSE that I am supposed to measure the length of with one or several ne555 timers. I'm only supposed to measure if it is longer, shorter or as long as 5ms. I'm supposed to have two outputs u0 and u0 and the truth table shuld look like this: 0 0 - "Measure in progress" 1 0 - "Shorter pulse than expected recieved" 0 1 - "Error" 1 1 - "Excpected or longer pulse recieved. I had a thought about using only a monostable ne555 and som inverters but I haven't really been able to implement it. Please help.