digital in sensitivity - building a fencing box

Hi all,

At present I am trying to build fencing scoring apparatus, what we call in the sport simply a 'box'. This is one of my first arduino projects and I am a beginner when it comes to electronics. Programming is more my game.

Anyway at the moment I've got a weapon with a button tip hooked up to the arduino. The way that it is meant to work is that when the button is depressed it breaks the circuit and a light shows indicating a hit. Now I've got this working all very well. However, I am having an issue with the sensitivity of the tip. You see when I depress the tip ever so slightly the digital pin registers this increase as a LOW, thus turning on the light. What I'd like to know if there's a way to get the input to withstand more resistance before it changes to the LOW state. It's quite important as there are rules about all this sort of thing - actually I think its somewhere in the region of 200ohms before it should register.

Cheers in advance,


While your explaination is good I think that you need to supply a wiring diagram showing the switch, light, voltage source, ground and connection to the Arduino. I'm sure there is something simple that can be done either with external components or with software to make it function like you wish, but more circuit detail is needed.


If you know the resistance value you want to use then have a pull up resistor of that value and connect your probe to ground. Then use an analogue input pin and read it using an analogue read. Then when the reading is below half way (512) you register a hit.

Excellent, thanks mike. Analogue it is!