PR11 FOR loop count

[fir]

I want to ask if I changed the number of loop to (original is 2000) 1000, 1500, 2500 and 3000; what will happened to the reading of the temperature on LCD?
Thanks in advance.

[shahrul]

That number is like number of sampling. The ADC take 2000 reading and get the average.
It effect depends on application. If you are reading parameter that not much varying, it's not many affected.
If you are reading parameter is like have some spike, this average value will help to read this.

[fir]

I see. I need to make the changes in those looping cycle but unfortunately my PR11 doesn't work.
So, in your opinion how much the temperature will deviate from 2000 cycle? say ±1°C for every 500 cycle changed?
Thanks in advance.

[shahrul]

I see. I need to make the changes in those looping cycle but unfortunately my PR11 doesn't work.
So, in your opinion how much the temperature will deviate from 2000 cycle? say ±1°C for every 500 cycle changed?
Thanks in advance.

Don't know. You also can use this method for temperature LM35.

[fir]

Last question. Is there any negative effects if the cycle loop set too high? For example the software crash or etc.

[shahrul]

Last question. Is there any negative effects if the cycle loop set too high? For example the software crash or etc.

Software will not crash.. It's just effect your reading performance. If the value high, it's increase reading time.

[ober]

You can change the value of reading, but remember to change the value for averaging right after the loop, which in original sample code, the result_temp is divided by 2000. There is no negative effect, as shahrul said, it will take longer time if the loop is more compared to less sample reading. You can take 1 reading if you like. This is like what we did in bio, physic or chemical lab during secondary school, taking more sample will average out the noise and offer nearer data to real result.

[fir]

Thanks Ober and Shahrul, your guys opinion conclude my project. Thanks again

[black_smtk]

can someone give me the pwm driver circuit for dc motor? need to control fan speed based on temperature

[shahrul]

can someone give me the pwm driver circuit for dc motor? need to control fan speed based on temperature

You can use motor driver L298 or can use mosfet IRF540 if only use one direction.