Piezo readings to ADC

Hi:

What circuit will give me the first (highest) value of a Piezo disc read with an ADC (ADC0831)? When I hit the Piezo the ADC , which is connected to a Parallax Stamp, it reads at least 3 to 4 values ,for example ; 100 (first value), 47 , 5, 2..... I will like to include a circuit that will give me only the first value , or maybe an average of the set of values. Tell me the name of the circuit and I will "google" it.

The piezo is connected to the ADC with a Resistor (1M) and Capacitor (101) in parallel to ground. On the Positive side of the piezo I add a Diode with +5V. I notice better readings with the diode included in the input circuit.

I already try using a PAUSE command to the ADC readings ; that reduce the number of readings in the set; but slowdown to much the reading. This is for a MIDI Percussion controller; therefore by ear I know it is not correct.

Thanks,
PRPROG

Why not do that in the Stamp software?

A "Peak detector" but you'll need to reset it after your reading so that it can measure the next peak. The diode and cap are a form of peak detector, with the 1Meg resistor discharging the cap.

Or just do it in software as Carl already suggested.....

Ian Rogers said:

Or just do it in software as Carl already suggested.....

Click to expand...

Thanks Crutschow for the suggestion...but adding a coding solution might work in more faster microprocessors but not on the Stamp II. At least in this case the delay is perceptible when playing faster notes. A hardware solution is my other option. I and considering Moffy's suggestion on a peak detector. I will do some research on the web.

Thanks,
PRPROG

So what is the processor doing with the ADC words?

crutschow said:

So what is the processor doing with the ADC words?

Click to expand...

Once it initialze the ADC0831 and read the values it convert (divide by 2 or MAX to a value of 127) , construct a MIDI message and send to a MIDI out port to a sound module. Not too much, but as I add code the basic program (IF , Loops, etc) the latency increment and it does not work......"musically" speaking that is.