wiki.raudys.com

pigpio yra kita biblioteka kontroliuoti GPIO, jie turiu geresni/tikslesni DMA paremta softwarini PWM. PWM reikalingas servo motorams kontroliuoti.

• http://abyz.co.uk/rpi/pigpio/

#include <stdio.h>
#include <stdlib.h>
#include <signal.h>
 
#include <termios.h> 
#include <unistd.h>  
 
#include <pigpio.h>
 
// gcc -Wall -pthread -o pigpio_spwm pigpio_spwm.c -lpigpio -O3
// sudo ./pigpio_spwm
 
int main(int argc, char *argv[])
{
    static struct termios oldt, newt;
    tcgetattr( STDIN_FILENO, &oldt);
    newt = oldt;
    newt.c_lflag &= ~(ICANON | ECHO);          
    tcsetattr( STDIN_FILENO, TCSANOW, &newt);
 
   if (gpioInitialise() < 0) return -1;
   //gpioSetMode(21, PI_OUTPUT);
   //gpioSetPWMfrequency(21, 10000);
   //gpioSetPWMrange(21, 2000);
 
    int p = 0;
 
    printf("Press e to exit program\n");
    printf("press q and w to increase and decrease software pwm\n");
    int c;  
    while((c=getchar())!= 'e')
    {      
        if (c == 'q') p ++;
        if (c == 'w') p --;
        printf("%d  \r",p);
        gpioPWM(21, p); 
    } 
 
   tcsetattr( STDIN_FILENO, TCSANOW, &oldt);
   return 0;   
}