144 lines
2.6 KiB
C
144 lines
2.6 KiB
C
#include <wiringPi.h>
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#include <stdio.h>
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#include <stdlib.h>
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#include <stdint.h>
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typedef struct {
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unsigned int ccr;
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unsigned int arr;
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unsigned int div;
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unsigned int div_stepping;
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} pwm_info;
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static pwm_info pwm_info_t;
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static void set_pwm_info(int pin)
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{
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int model;
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piBoardId (&model);
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switch (model)
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{
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case PI_MODEL_BERRY:
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case PI_MODEL_ZERO:
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if (pin != 2 ) {
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fprintf (stderr, "the pin you choose doesn't support hardware PWM\n") ;
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exit(1);
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}
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pwm_info_t.ccr = 512;
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pwm_info_t.arr = 1024;
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pwm_info_t.div = 1;
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pwm_info_t.div_stepping = 1;
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break;
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default:
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printf("Oops - unable to determine board type...");
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exit(1);
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}
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}
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int main(int argc, char *argv [])
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{
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int i = 0;
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int val = 0;
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int pin= 0;
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if (argc != 2) {
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fprintf (stderr, "Usage: %s <pin>\n", argv [0]) ;
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exit (1) ;
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}
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pin = (unsigned int)strtoul (argv [1], NULL, 10) ;
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// 初始化
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printf("wiringPiSetup start\n");
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wiringPiSetup();
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set_pwm_info(pin);
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pinMode(pin,PWM_OUTPUT);
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printf("wiringPiSetup end\n");
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// 开始测试
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while(1) {
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pwmSetRange(pin,pwm_info_t.arr);
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pwmSetClock(pin,pwm_info_t.div);
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pwmWrite(pin,pwm_info_t.ccr);
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//1. 调节PWM占空比
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//1.1 通过设置ARR调节PWM占空比
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printf("Modified ARR test start\n");
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for (i = 0 ; i <= 8 ; i++) {
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pwmSetRange(pin,pwm_info_t.arr + i * (pwm_info_t.arr / 8));
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delay(500);
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}
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delay(5000);
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for (i = 7 ; i >= 0 ; i-- ) {
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pwmSetRange(pin,pwm_info_t.arr + i * (pwm_info_t.arr / 8));
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delay(500);
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}
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delay(5000);
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printf("Modified ARR test end\n");
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//1.2 通过设置CCR调节PWM占空比
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printf("Modified CCR test start\n");
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for (i = 0 ; i <= 8 ; i++) {
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pwmWrite(pin,pwm_info_t.ccr + i * (pwm_info_t.ccr / 8));
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delay(500);
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}
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delay(5000);
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for (i = 7 ; i >= 0 ; i-- ) {
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pwmWrite(pin,pwm_info_t.ccr + i * (pwm_info_t.ccr / 8));
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delay(500);
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}
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delay(5000);
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printf("Modified CCR test end\n");
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//2.调节PWM频率
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//2.1通过设置分频系数调节PWM频率
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printf("Modified frequency division test start\n");
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for (i = pwm_info_t.div_stepping ; i <= 10 * pwm_info_t.div_stepping; i += pwm_info_t.div_stepping) {
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pwmSetClock(pin,i);
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delay(500);
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}
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delay(5000);
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for (i = 9 * pwm_info_t.div_stepping; i >= pwm_info_t.div_stepping ; i -= pwm_info_t.div_stepping) {
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pwmSetClock(pin,i);
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delay(500);
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}
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delay(5000);
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printf("Modified frequency division test end\n");
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//2.2 直接设置PWM频率
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printf("Modified PWM frequency test start\n");
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for (i = 1 ; i <= 10; i++) {
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pwmToneWrite(pin,2000 * i);
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delay(2000);
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}
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delay(5000);
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printf("Modified PWM frequency test end\n");
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}
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}
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