Contents
How PWM generates a microcontroller signal?
Programming PIC to generate PWM signals:
- Set the PWM period by writing to the PR2 register.
- Set the PWM duty cycle by writing to the CCPR1L register and CCP1CON<5:4> bits.
- Make the CCP1 pin an output by clearing the TRISC<2> bit.
- Set the TMR2 prescale value and enable Timer2 by writing to T2CON.
What is PWM microcontroller?
Pulse Width Modulation (PWM) is a technique where the width of digital pulses is adjusted to generate different average dc voltages. Most microcontrollers have a built-in timer that can be used to generate a PWM signal.
What are the methods used to generate PWM signals?
One of the simplest methods of generating a PWM signal is to compare two control signals, a carrier signal and a modulation signal. This is known as carrier-based PWM. The carrier signal is a high frequency (switching frequency) triangular waveform. The modulation signal can be any shape.
Which is microcontroller is used for PWM generation?
In this tutorial we are using PIC 16F877A for demonstrating PWM generation using CCP module. PIC 16F877A contains two CCP modules. In the below circuit four switches are provided for controlling the Duty Ratio of PWM generated by two CCP modules of the PIC Microcontroller.
How to generate a PWM signal in Pic?
The program involves the PIC Timer Module and PIC ADC Module to create a PWM signal based with a varying Duty cycle according to the ADC value form the POT. If you are new to using these modules then it is strongly recommended to read the appropriate tutorial by clicking on the hyperlinks.
How is mikroC used in a PIC microcontroller?
MikroC for PIC PWM Library As mentioned earlier, MikroC provides a built-in library for pulse width modulation module of pic microcontroller. This library is generic and can be used with all PIC16F, PIC18 series microcontrollers. These are the four functions that are used to generate PWM, set frequency and change duty cycle.
How to change module number for PWM generation?
Note 1 : For microcontrollers with more than one CCP module, to use the desired CCP module for PWM generation simply change the number “1” in the prototype with desired module number. eg: PWM2_Init (5000), PWM2_Start ().