Mega ANALOG INPUT resolution 255???

Projects General Guidance
1

I'm playing around with some piezo transducers I purchased. For a quick immersion into it I uploaded the sketch from here.

The only change I made was the serial output from "knock" to the value. Shouldn't I be getting values from 100 (threshold) to 1023? I'm only getting values to 255. I did make one other change explicitly declaring pin 0 as an input since I understand output only has a resolution of 0-255.

If it makes any difference, this is an Arduino Mega1280. I get the same result on a Funduino Mega 2560

Thanks

2

That sketch, for some unknown reason, reads the result of analogRead into an eight bit variable, so it isn't surprising you only get 0...255

3

If what AWOL said isn't clear, change "byte val" to "int val" at the start - that declares val as an int which can store numbers above 255.

4

Oh duh.

Didn't notice the byte declaration... that should do it.

Thanks!