I've recently got an arduino board (mega 2560) and I'd like to start making a basic piezo drum trigger as a simple project to get started with arduino.

I've connected a piezo with a 1MOhm resistor wired in parallel to the arduino and I'm getting nice, readable values in the arduino serial monitor (between 0-1023).

So the next step would be to use the comport object in PD to receive the serial output from arduino then divide it by 8 to get a value between 0-127, right?

But when I activate the comport in PD, arduino's serial monitor starts displaying weird ASCII characters. It's the same situation if I try to use a potentiometer - fine before opening the comport and a seemingly meaningless mess once it is open.

Is there an issue with my system or am I missing a step?

Any help would be greatly appreciated.

You might want to have a look at the [pduino/arduino] object in Pd-extended. If all you need is numbers, it makes it really easy. You just load the Standard Firmata to the board, activate the input pin from within Pd, and you should get some values coming in.

Do you upload the Standard Firmata sketch in the usual fashion? But then it will be erased when I upload my piezo drum trigger sketch, right? Or do I just write the drum trigger sketch within the Firmata one?

Thanks

Well, the idea of using the Standard Firmata and [arduino] is that you don't have to write your own sketch. You just do everything in Pd instead.