Thank you very much for the pointers and advice. It's exactly what I was looking for to get started.
I'm sure I will have more questions in the near future. This will end up being a fairly involved project dealing with sensor manipulation of my vehicle where I'm going to try to make otherwise impossible adjustments to the fuel injection system.
I just found this and it looks like what I need to begin
/*Example 22.1 Measuring range of analogRead() using a 1.8V AREF voltage
tronixstuff.com/tutorials CC by-sa-nc
*/
int analoginput = 0; // our analog pin
int analogamount = 0; // stores incoming value
float percentage = 0; // used to store our percentage value
float voltage =0; // used to store voltage value
void setup()
{
Serial.begin(9600);
analogReference(EXTERNAL); // use AREF for reference voltage
}
void loop()
{
delay(200);
analogamount=analogRead(analoginput);
percentage=(analogamount/1024)*100;
voltage=analogamount*1.75; // in millivolts
Serial.print("Percentage of AREF: ");
Serial.println(percentage,2);
Serial.print("voltage on analog input (mV): ");
Serial.println(voltage,2);
}
I'll be back after I've done some experimenting/testing
Thanx!