min ji Kim / Mbed 2 deprecated Nucleo_digtal_pwm

Make PWM pulse use digital output with Timer

Dependencies:   mbed

main.cpp@0:eb891a3bc014, 2016-01-27 (annotated)

Committer:
Kmj
Date:
Wed Jan 27 04:55:43 2016 +0000
Revision:
0:eb891a3bc014
This is remake version of Nucleo_pwm3.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
Kmj 0:eb891a3bc014 1 #include "mbed.h"
Kmj 0:eb891a3bc014 2
Kmj 0:eb891a3bc014 3 Timeout timer;
Kmj 0:eb891a3bc014 4 InterruptIn my_button(USER_BUTTON);
Kmj 0:eb891a3bc014 5 DigitalOut my_pwm(LED1); // IO used by pwm_io function
Kmj 0:eb891a3bc014 6
Kmj 0:eb891a3bc014 7 int on_delay = 0;
Kmj 0:eb891a3bc014 8 int off_delay = 0;
Kmj 0:eb891a3bc014 9 float duty[5]={0.2f,0.4f,0.6f,0.8f,1.0f};
Kmj 0:eb891a3bc014 10 int i=0;
Kmj 0:eb891a3bc014 11 void toggleOff(void);
Kmj 0:eb891a3bc014 12
Kmj 0:eb891a3bc014 13 void toggleOn(void) {
Kmj 0:eb891a3bc014 14 my_pwm = 1;
Kmj 0:eb891a3bc014 15 timer.attach_us(toggleOff, on_delay);
Kmj 0:eb891a3bc014 16 }
Kmj 0:eb891a3bc014 17
Kmj 0:eb891a3bc014 18 void toggleOff(void) {
Kmj 0:eb891a3bc014 19 my_pwm = 0;
Kmj 0:eb891a3bc014 20 timer.attach_us(toggleOn, off_delay);
Kmj 0:eb891a3bc014 21 }
Kmj 0:eb891a3bc014 22
Kmj 0:eb891a3bc014 23 // p_us = signal period in micro_seconds
Kmj 0:eb891a3bc014 24 // dc = signal duty-cycle (0.0 to 1.0)
Kmj 0:eb891a3bc014 25 void pwm_io(int p_us, float dc) {
Kmj 0:eb891a3bc014 26 timer.detach();
Kmj 0:eb891a3bc014 27 if ((p_us == 0) || (dc == 0)) {
Kmj 0:eb891a3bc014 28 my_pwm = 0;
Kmj 0:eb891a3bc014 29 return;
Kmj 0:eb891a3bc014 30 }
Kmj 0:eb891a3bc014 31 if (dc >= 1) {
Kmj 0:eb891a3bc014 32 my_pwm = 1;
Kmj 0:eb891a3bc014 33 return;
Kmj 0:eb891a3bc014 34 }
Kmj 0:eb891a3bc014 35 on_delay = (int)(p_us * dc);
Kmj 0:eb891a3bc014 36 off_delay = p_us - on_delay;
Kmj 0:eb891a3bc014 37 toggleOn();
Kmj 0:eb891a3bc014 38 }
Kmj 0:eb891a3bc014 39 void pressed()
Kmj 0:eb891a3bc014 40 { if(i>=5)
Kmj 0:eb891a3bc014 41 i=0;
Kmj 0:eb891a3bc014 42
Kmj 0:eb891a3bc014 43 pwm_io(20000,duty[i]);
Kmj 0:eb891a3bc014 44 i++;
Kmj 0:eb891a3bc014 45 }
Kmj 0:eb891a3bc014 46
Kmj 0:eb891a3bc014 47 int main() {
Kmj 0:eb891a3bc014 48 my_button.fall(&pressed);
Kmj 0:eb891a3bc014 49 pwm_io(20000, 0.25); // 20ms - 25%
Kmj 0:eb891a3bc014 50
Kmj 0:eb891a3bc014 51 while(1) {
Kmj 0:eb891a3bc014 52
Kmj 0:eb891a3bc014 53 }
Kmj 0:eb891a3bc014 54 }
Kmj 0:eb891a3bc014 55