Raspberry Pi B ，L293D和两个DC电机，带PWM的可变速度，C/C 的代码，但不起作用

Question

在这里我的代码，它运行，没有错误，但是车轮上没有旋转。我的设置：1.覆盆子Pi B 2. DC电动机的L293D3.两个直流电动机4.使用WireingPi库

示例1：

#include <iostream>
#include <wiringPi.h>
#include <softPwm.h>
using namespace std;
// motor pins (pwm)
// motor left
int motor_l_u = 26;
int motor_l_v = 27;
// motor right
int motor_r_u = 28;
int motor_r_v = 29;
// pwm
int pwmValue = 1023;
int pwmValueInit = 0;
int main(void) {
if (wiringPiSetup() == -1)
    return -1;
if (wiringPiSetupSys() == -1)
    return -1;
pinMode(motor_l_u, OUTPUT);
pinMode(motor_l_v, OUTPUT);
pinMode(motor_r_u, OUTPUT);
pinMode(motor_r_v, OUTPUT);
digitalWrite(motor_l_u, LOW); // at start turn off the GPIO
digitalWrite(motor_l_v, LOW); // at start turn off the GPIO
digitalWrite(motor_r_u, LOW); // at start turn off the GPIO
digitalWrite(motor_r_v, LOW); // at start turn off the GPIO
pinMode(motor_l_u, PWM_OUTPUT);
pinMode(motor_l_v, PWM_OUTPUT);
pinMode(motor_r_u, PWM_OUTPUT);
pinMode(motor_r_v, PWM_OUTPUT);
// prepare GPIOs for motors
softPwmCreate(motor_l_u, pwmValueInit, pwmValue);
softPwmCreate(motor_l_v, pwmValueInit, pwmValue);
softPwmCreate(motor_r_u, pwmValueInit, pwmValue);
softPwmCreate(motor_r_v, pwmValueInit, pwmValue);
// acceleration forward
for (int var = 0; var < pwmValue; ++var) {
    if (debug == 1) {
        cout << "set speed to " << var << endl;
    }
    softPwmWrite(motor_r_u, (pwmValue - var));
    softPwmWrite(motor_r_v, var);
    softPwmWrite(motor_l_u, var);
    softPwmWrite(motor_l_v, (pwmValue - var));
    delay(10);
}
// acceleration backward
for (int var = 0; var < pwmValue; ++var) {
    if (debug == 1) {
        cout << "set speed to " << var << endl;
    }
    softPwmWrite(motor_r_u, var);
    softPwmWrite(motor_r_v, (pwmValue - var));
    softPwmWrite(motor_l_u, (pwmValue - var));
    softPwmWrite(motor_l_v, var);
    delay(10);
}
return -1;
}

我的另一个例子是这样，但是在轮子上编译旋转时没有错误。

#include <iostream>
#include <wiringPi.h>
#include <softPwm.h>
using namespace std;
// motor pins (pwm)
// motor left
int motor_l_u = 26;
int motor_l_v = 27;
// motor right
int motor_r_u = 28;
int motor_r_v = 29;
// pwm
int pwmValue = 1023;
int pwmValueInit = 0;
int main(void) {
if (wiringPiSetup() == -1)
    return -1;
if (wiringPiSetupSys() == -1)
    return -1;
pinMode(motor_l_u, OUTPUT);
pinMode(motor_l_v, OUTPUT);
pinMode(motor_r_u, OUTPUT);
pinMode(motor_r_v, OUTPUT);
digitalWrite(motor_l_u, LOW); // at start turn off the GPIO
digitalWrite(motor_l_v, LOW); // at start turn off the GPIO
digitalWrite(motor_r_u, LOW); // at start turn off the GPIO
digitalWrite(motor_r_v, LOW); // at start turn off the GPIO
pinMode(motor_l_u, PWM_OUTPUT);
pinMode(motor_l_v, PWM_OUTPUT);
pinMode(motor_r_u, PWM_OUTPUT);
pinMode(motor_r_v, PWM_OUTPUT);
// prepare GPIOs for motors
pwmWrite(motor_l_u, pwmValueInit);
pwmWrite(motor_l_v, pwmValueInit);
pwmWrite(motor_r_u, pwmValueInit);
pwmWrite(motor_r_v, pwmValueInit);
// acceleration forward
for (int var = 0; var < pwmValue; ++var) {
    if (debug == 1) {
        cout << "set speed to " << var << endl;
    }
    pwmWrite(motor_r_u, (pwmValue - var));
    pwmWrite(motor_r_v, var);
    pwmWrite(motor_l_u, var);
    pwmWrite(motor_l_v, (pwmValue - var));
    delay(10);
}
// acceleration backward
for (int var = 0; var < pwmValue; ++var) {
    if (debug == 1) {
        cout << "set speed to " << var << endl;
    }
    pwmWrite(motor_r_u, var);
    pwmWrite(motor_r_v, (pwmValue - var));
    pwmWrite(motor_l_u, (pwmValue - var));
    pwmWrite(motor_l_v, var);
    delay(10);
}
return -1;
}

我看不到我的问题:-(。请不要发布python代码。

Answer 1

本节是错误的

pinMode(motor_l_u, OUTPUT);
pinMode(motor_l_v, OUTPUT);
pinMode(motor_r_u, OUTPUT);
pinMode(motor_r_v, OUTPUT);
digitalWrite(motor_l_u, LOW); // at start turn off the GPIO
digitalWrite(motor_l_v, LOW); // at start turn off the GPIO
digitalWrite(motor_r_u, LOW); // at start turn off the GPIO
digitalWrite(motor_r_v, LOW); // at start turn off the GPIO
pinMode(motor_l_u, PWM_OUTPUT);
pinMode(motor_l_v, PWM_OUTPUT);
pinMode(motor_r_u, PWM_OUTPUT);
pinMode(motor_r_v, PWM_OUTPUT);