[Solved] Difference between Hardware and Software PWM.
Richu Bini last edited by salmanfaris
What is the difference between hardware pwm and software pwm
kowshik1729 last edited by
@Richu-Bini thanks for posting the question . just for a brief about pwm, pulse width modulation technique is a method to change the duty cycle of a wave. Which means you can determine how much time a signal must be on or off.
So, coming to the question, software pwm and hardware pwm is just two different ways of producing same result. In software(referring Arduino here) you'll just write a value between 0 to 255 inorder to determine duty cycle percentage. For example 0 is 0% duty cycle which means the cycle is on for 0% of whole time, similarly 127 means 50% of time cycle will be on and 255 means signal will be on for ever. This is regarding software.
Coming to hardware, you can generate a pwm signal using very simple passive component, called as potentiometer and 555 timer IC by using 555 timer as bistable multivibrator(The generated output will have two stable states 0 and Vmax, hence the name bistable) and changing the resistance using a potentiometer generates different duty cycles. This is the difference between hardware and software pwm. Please let me know if I haven't explained what you have expected.
Richu Bini last edited by
This link has even more extensive ways to do it
The way that I've seen most people do it (have a look on the Raspberry Pi forums), and have done myself with success is using /etc/rc.local.
All you need to do here is put ./myscript in the rc.local text file. If it's in python, put python myscript.py.
This literally is "a simple solution, (like dropping my script in some "startup" directory or something similar)"- maybe search on the forums when you're having questions as well, this solution came up on the first 4 results of a google search!
i need to run a QT application on BOOT. and i want to disable all controls like minimize application, close application.
Anyone have experience in this? please help me.
@mubassir-mk Glad that it helped.
@kowshik1729 Thank you....
Very help full your replay ...