I bought a kit with some parts to build a bluetooh-controlled toy car, but I can't get it to work, I'm still a beginner and I don't know what could be happening. any suggestion will be welcome.
This is the code that comes with the kit:
#include <SR04.h>
#include <AFMotor.h>
//2022.8.15
//Configure THE PWM control pin
const int PWM2A = 11; //M1 motor
const int PWM2B = 3; //M2 motor
const int PWM0A = 6; //M3 motor
const int PWM0B = 5; //M4 motor
const int DIR_CLK = 4; // Data input clock line
const int DIR_EN = 7; //Equip the L293D enabling pins
const int DATA = 8; // USB cable
const int DIR_LATCH = 12; // Output memory latch clock
//Define the pin of ultrasonic obstacle avoidance sensor
const int Trig = A2; //A2 is defined as the pin Trig connected to the ultrasonic sensor
const int Echo = A3; //A3 is defined as the pin Echo connected to the ultrasonic sensor
//Define motion state
const int Forward = 39; //39 save to Forward
const int Back = 216; //216 save to Back
const int Left = 116; //116 save to Left
const int Right = 139; //139 save to right
const int Stop = 0; //Parking variable
const int L_turn = 106; //turn left
const int R_turn = 149; //turn right
//Set the default speed between 1 and 255
int Speed1 = 180;
int Speed2 = 180;
int Speed3 = 180;
int Speed4 = 180;
int distance = 0; //Variables for storing ultrasonic sensor measurements
char serialData; //put the data received by the serial port in serialData
char cmd; //Store bluetooth receive commands
void setup()
{
Serial.begin(9600);//Set the serial port baud rate 9600
//Configure as output mode
pinMode(DIR_CLK,OUTPUT);
pinMode(DATA,OUTPUT);
pinMode(DIR_EN,OUTPUT);
pinMode(DIR_LATCH,OUTPUT);
pinMode(PWM0B,OUTPUT);
pinMode(PWM0A,OUTPUT);
pinMode(PWM2A,OUTPUT);
pinMode(PWM2B,OUTPUT);
pinMode(Trig,OUTPUT);//The Trig pin connected to the ultrasound is set to output mode
pinMode(Echo,INPUT);//The Echo pin connected to the ultrasound is set to input mode
void Motor(int Dri,int Speed1,int Speed2,int Speed3,int Speed4);
int SR04(int Trig,int Echo);
void AvoidingObstacles();
void HC05();
}
void loop()
{
distance = SR04(Trig,Echo); //Acquisition of ultrasonic distance
HC05(); //Call the Bluetooth car control function
}
/* Function name: Motor();
* Function: Change the movement direction and speed of the car through the entrance parameters
* Entry parameter 1: Dri car movement direction
* Entry parameters 2~3: Speed1~Speed4 motor speed, value range 0~255
* Dri value description (forward :39; Back: 216; Left translation: 116; Right translation: 139; Stop: 0;
* Right rotation: 106; Left rotation: 149)
* Return value: None
*/
void Motor(int Dir,int Speed1,int Speed2,int Speed3,int Speed4)
{
analogWrite(PWM2A,Speed1); //Motor PWM speed regulation
analogWrite(PWM2B,Speed2); //Motor PWM speed regulation
analogWrite(PWM0A,Speed3); //Motor PWM speed regulation
analogWrite(PWM0B,Speed4); //Motor PWM speed regulation
digitalWrite(DIR_LATCH,LOW); //DIR_LATCH sets the low level and writes the direction of motion in preparation
shiftOut(DATA,DIR_CLK,MSBFIRST,Dir);//Write Dir motion direction value
digitalWrite(DIR_LATCH,HIGH);//DIR_LATCH sets the high level and outputs the direction of motion
}
/*
Function name: SR04()
Function: Obtain ultrasonic ranging data
Entry parameters: Trig, Echo
Function return value: cm
*/
int SR04(int Trig,int Echo)
{
digitalWrite(Trig,LOW); //Trig is set to low level
delayMicroseconds(2); //Wait 2 microseconds
digitalWrite(Trig,HIGH); //Trig is set to high level
delayMicroseconds(10); //Wait 15 microseconds
digitalWrite(Trig,LOW); //Trig is set to low
float cm = pulseIn(Echo,HIGH)/58; //Convert the ranging time to CM
Serial.print("Distance:"); //Character Distance displayed in serial port monitor window:
Serial.print(cm);
Serial.println("cm");
return cm; //Returns cm value ranging data
}
/*
* Function name: HC05()
* Function: Receive Bluetooth data, control the car movement direction
* Entry parameters: None
* Return value: None
*/
void HC05()
{
if(Serial.available() > 0) //Determine if the received data is greater than 0
{
serialData = Serial.read(); //Receiving function
if ('F' == serialData ) cmd = 'F'; //If the data received by the serial port is character F, save F to CMD
else if('B' == serialData ) cmd = 'B'; //If the data received by the serial port is character B, save F to CMD
else if('L' == serialData ) cmd = 'L'; //If the serial port receives data as the character L, save F to CMD
else if('R' == serialData ) cmd = 'R'; //If the serial port receives data as the character R, save F to CMD
else if('S' == serialData ) cmd = 'S'; //If the serial port receives data as character S, save F to CMD
else if('C' == serialData ) cmd = 'C';
else if('D' == serialData ) cmd = 'D';
else if( serialData == '+' && Speed1 < 245)//If you receive a string plus, the speed increases
{
Speed1 += 10; //We're going to increase the velocity by 10 at a time
Speed2 = Speed1;
Speed3 = Speed1;
Speed4 = Speed1;
}
else if( serialData == '-' && Speed1 > 30)//When I receive a string -- the speed decreases
{
Speed1 -= 10; //I'm going to subtract 10 at a time
Speed2 = Speed1;
Speed3 = Speed1;
Speed4 = Speed1;
}
// else if('A' == serialData)
// {
// AvoidingObstacles();//The ultrasonic obstacle avoidance function is called to realize the obstacle avoidance function
// }
}
if('F' == cmd) //If Bluetooth receives the string F, the dolly moves forward and enables obstacle avoidance
{
AvoidingObstacles();//
}
else if('B' == cmd) //Bluetooth receives string B, car backs up
{
Motor(Back,Speed1,Speed2,Speed3,Speed4);
}
else if('L' == cmd) //Bluetooth received the string L, car left translation
{
Motor(Left,Speed1,Speed2,Speed3,Speed4);
}
else if('R' == cmd) //Bluetooth received the string R
{
Motor(Right,Speed1,Speed2,Speed3,Speed4); //right translation
}
else if('S' == cmd) //When the string S is received, the cart stops moving
{
Motor(Stop,0,0,0,0);
}
else if('C' == cmd) //Bluetooth received the string C
{
Motor(L_turn,Speed1,Speed2,Speed3,Speed4); //turn left
}
else if('D' == cmd) //Bluetooth received the string D
{
Motor(R_turn,Speed1,Speed2,Speed3,Speed4); //turn right
}
}
void AvoidingObstacles()
{
if((distance > 20 ) || cmd == 'F')//If the distance is greater than 20cm or bluetooth receives a command equal to F
{
delay(100);//Delay of 100 ms
if(distance > 20)//Again, determine if the distance is really greater than 20cm
{
Motor(Forward,Speed1,Speed2,Speed3,Speed4); //Call forward function
}
else //Otherwise the distance is less than 20
{
Motor(Back,Speed1,Speed2,Speed3,Speed4);//retreat
delay(500);
Motor(106,Speed1,Speed2,Speed3,Speed4);//Turn left to change the direction of the car
delay(500);
}
}
}
