Signal processing

I am new to the Arduino environment. I am using an Arduino Duemilanove for a course project and hoping to take some pulse signals from a pulse oximeter we have built in lab.

I would like to find the peaks (min, max) of the incoming signal from the pulse oximeter.

Could anyone help with how to proceed and whether it is possible to find the min and the max of the signal (sine wave) in real time?

When reading a sensor value, you get the instantaneous value at that point in time. In other words, a single value. Not a sine wave.

The value will be an integer between 0 and 1023, inclusive. The value represents the relative value of the analog pin voltage with respect to VRef.

It is, then, a trivial matter to determine the maximum and minimum value in any given time period.

signal (sine wave) in real time?

It's a pulse - is it really a sine wave? (I think not).

Say a resting pulse of 70 beats per minute (I think mine's about 55), so that's a little over 1.1Hz.

Not going to be difficult, I think.