temperature formula found

so last night i was working on the whole brewery monitoring device and getting the degrees F of the probe.

I found out that it was incredibly easy. so the arduino card on the analog read gets a value in increments of (5/1024) or 0.0048828125V. the reported value returns how many steps of that voltage it is reporting. so the actual value is like 315 for about 34F and 348 for 66F.

after staring at that for a while, i was trying to hard to figure out a formula. then out of more of a desperation move, i thought, i wonder what the difference is. After some subtracting I found that it seems to be reporting the degrees F + 282.

so in short, its the reported value – 282 = degrees F. so now my code looks like this

int pin = 0; // analog pin
int tempf=0; // temperature variable
int samples[10]; // variables to make a better precision
int serialByte = 0;//incoming serial byte
int i;

void setup()
  Serial.begin(57600); // start serial communication
void loop()
  if (Serial.available() > 0) {
    serialByte = Serial.read();
    //do not allow other pins to be read.
    if(serialByte >=48 && serialByte <= 53) {
      //get multiples and take average for more stable reading
      for(i = 0;i<=9;i++){
        tempf = tempf + samples[i];
        //has a 10 second read period for the average
      int temp = (tempf/10)-282;
      //return the degrees F.
      //will automatically be sent through xbee

now just have to do the web portal code and the windows app to upload to the database the web portal reads from.
and my code tags dont seem to work…


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