Hi,

I am running a motor, which goes faster if I increase the temperature by pinching the temperature sensor.

I am trying to check if "Current_Temperature > Original Temperature + 2" to sense the increase in temperature. So initially in while loop, I set temp1 to be original temperature. Then I check if the average temperature has gone over original temperature+2. The problem is that it goes through the if statement instantaneously. What could I do?

  temp_avg = 0.0;
    for(i=0; i<100; i++) {
      last_sample = adc_read();
      this_temp = sampleToFahrenheit(last_sample);

      // add this contribution to the average
      temp_avg = temp_avg + this_temp/100.0;
    }

    if(j = 0){
        temp1= temp_avg;
        j++;
        }

    if(temp_avg > (temp1+2)){
            lcd_write_string(PSTR("HELLO"));
            pwm_set(pos);
            }

The problem is that it goes through the if statement instantaneously. What could I do?

Well at the very least you could put in a delay.

delay_ms(500);

Ralph

chaosatom -

Your first "if" statement will never execute the code inside the braces. When you write:

if(j = 0){

You're assigning j the value 0, which evaluates to "false". For a comparison you need a double "=" sign:

if(j == 0){

The rest looks good.

Thanks for the advice guys.

I got it to work. That if statement was a problem. Also the time delay code would help me as well.

Great.

Did you get the PWM output to vary the motor speed? I'm curious which transistors and flyback diodes you decided on and how it was wired.

Yes, I decided to go with the 2N7000 transistor. For diode, I had one lying around (not sure about the name).

The wiring was done exactly as shown in this tutorial. http://www.nerdkits.com/videos/motors_and_microcontrollers_101/

I had a separate 9V battery powering this.