*/
//Array, used to store the data of pattern, can be calculated by yourself or obtained from the modulus tool
unsigned char front[] = {0x00,0x00,0x00,0x00,0x00,0x24,0x12,0x09,0x12,0x24,0x00,0x00,0x00,0x00,0x00,0x00};
unsigned char left[] = {0x00,0x00,0x00,0x00,0x00,0x00,0x44,0x28,0x10,0x44,0x28,0x10,0x44,0x28,0x10,0x00};
unsigned char right[] = {0x00,0x10,0x28,0x44,0x10,0x28,0x44,0x10,0x28,0x44,0x00,0x00,0x00,0x00,0x00,0x00};
unsigned char STOP01[] = {0x2E,0x2A,0x3A,0x00,0x02,0x3E,0x02,0x00,0x3E,0x22,0x3E,0x00,0x3E,0x0A,0x0E,0x00};
unsigned char clear[] = {0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00};
#define SCL_Pin A5 //Set clock pin to A5
#define SDA_Pin A4 //Set data pin to A4
#define ML_Ctrl 4 //define direction control pin of B motor
#define ML_PWM 5 //define PWM control pin of B motor
#define MR_Ctrl 2 //define direction control pin of A motor
#define MR_PWM 9 //define PWM control pin of A motor
#include "SR04.h"//define the library of ultrasonic sensor
#define TRIG_PIN 12// set the signal input of ultrasonic sensor to D12
#define ECHO_PIN 13//set the signal output of ultrasonic sensor to D13
SR04 sr04 = SR04(ECHO_PIN,TRIG_PIN);
long distance,a1,a2;//define three distance
const int servopin = 10;//set the pin of servo to D10
void setup() {
Serial.begin(9600);//open serial monitor and set baud rate to 9600
pinMode(ML_Ctrl, OUTPUT);//set direction control pin of B motor to OUTPUT
pinMode(ML_PWM, OUTPUT);//set PWM control pin of B motor to OUTPUT
pinMode(MR_Ctrl, OUTPUT);//set direction control pin of A motor to OUTPUT
pinMode(MR_PWM, OUTPUT);//set PWM control pin of A motor to OUTPUT
servopulse(servopin,90);// the angle of servo is 90 degree
delay(300);
pinMode(SCL_Pin,OUTPUT);// set clock pin to OUTPUT
pinMode(SDA_Pin,OUTPUT);//set data pin to OUTPUT
matrix_display(clear);// Clear the matrix display
}
void loop()
{
avoid();//run the main program
}
void avoid()
{
distance=sr04.Distance(); //obtain the value detected by ultrasonic sensor
if((distance < 20)&&(distance > 0))//if the distance is greater than 0 and less than 20
{
car_Stop();//stop
matrix_display(STOP01); //show stop pattern
delay(100);
servopulse(servopin,180);//servo rotates to 180°
delay(500);
a1=sr04.Distance();//measure the distance
delay(100);
servopulse(servopin,0);//rotate to 0 degree
delay(500);
a2=sr04.Distance();//measure the distance
delay(100);
if(a1 > a2)//if distance a1 is greater than a2
{
car_left();//turn left
matrix_display(left); //display left-turning pattern
servopulse(servopin,90);//servo rotates to 90 degree
delay(600);
matrix_display(front); //show forward pattern
}
else//if the right distance is greater than the left
{
car_right();// turn right
matrix_display(right); // display right-turning pattern
servopulse(servopin,90);// servo rotates to 90 degree
delay(600);
matrix_display(front); //show forward pattern
}
}
else//otherwise
{
car_front();//go forward
matrix_display(front); // show forward pattern
}
}
void servopulse(int servopin,int myangle)//the running angle of servo
{
for(int i=0; i<30; i++)
{
int pulsewidth = (myangle*11)+500;
digitalWrite(servopin,HIGH);
delayMicroseconds(pulsewidth);
digitalWrite(servopin,LOW);
delay(20-pulsewidth/1000);
}
}
void car_front()//car goes forward
{
digitalWrite(ML_Ctrl,HIGH);//set direction control pin of B motor to HIGH level
analogWrite(ML_PWM,150);//set PWM control speed of B motor to 150
digitalWrite(MR_Ctrl,HIGH);//set direction control pin of A motor to HIGH level
analogWrite(MR_PWM,150);//set PWM control speed of A motor to 150
}
void car_back()//go back
{
digitalWrite(ML_Ctrl,LOW);//set direction control pin of B motor to LOW
analogWrite(ML_PWM,200);//set PWM control speed of B motor to 200
digitalWrite(MR_Ctrl,LOW);//set direction control pin of A motor to LOW
analogWrite(MR_PWM,200);//set PWM control speed of A motor to 200
}
void car_left()//car turns left
{
digitalWrite(ML_Ctrl,LOW);//set direction control pin of B motor to LOW
analogWrite(ML_PWM,200);//set PWM control speed of B motor to 200
digitalWrite(MR_Ctrl,HIGH);//set direction control pin of A motor to HIGH
analogWrite(MR_PWM,200);//set PWM control speed of A motor to 200
}
void car_right()//car turn rights
{
digitalWrite(ML_Ctrl,HIGH);//set direction control pin of B motor to HIGH
analogWrite(ML_PWM,200);//set PWM control speed of B motor to 200
digitalWrite(MR_Ctrl,LOW);//set direction control pin of A motor to LOW
analogWrite(MR_PWM,200);//set PWM control speed of A motor to 200
}
void car_Stop()//car stops
{
digitalWrite(ML_Ctrl,LOW);
analogWrite(ML_PWM,150);
digitalWrite(MR_Ctrl,LOW);
analogWrite(MR_PWM,150);
delay(50);
analogWrite(ML_PWM,0);//set PWM control speed of B motor to 0
analogWrite(MR_PWM,0);//set PWM control speed of A motor to 0
}
//this function is used for dot matrix display
void matrix_display(unsigned char matrix_value[])
{
IIC_start(); //the function to call the data transmission
IIC_send(0xc0); //Select address
for(int i = 0;i < 16;i++) //Pattern data has 16 bytes
{
IIC_send(matrix_value[i]); //data to convey patterns
}
IIC_end(); //end the transmission of patterns data
IIC_start();
IIC_send(0x8A); //display control, set pulse width to 4/16
IIC_end();
}
// the condition that data transmission starts
void IIC_start()
{
digitalWrite(SCL_Pin,HIGH);
delayMicroseconds(3);
digitalWrite(SDA_Pin,HIGH);
delayMicroseconds(3);
digitalWrite(SDA_Pin,LOW);
delayMicroseconds(3);
}
// transmit data
void IIC_send(unsigned char send_data)
{
for(char i = 0;i < 8;i++) //Every character has 8 bits
{
digitalWrite(SCL_Pin,LOW); //pull down the SCL_Pin to change the signal of SDA
delayMicroseconds(3);
if(send_data & 0x01) //1 or 0 of byte is used to set high and low level of SDA_Pin
{
digitalWrite(SDA_Pin,HIGH);
}
else
{
digitalWrite(SDA_Pin,LOW);
}
delayMicroseconds(3);
digitalWrite(SCL_Pin,HIGH); //Pull up SCL_Pin to stop data transmission
delayMicroseconds(3);
send_data = send_data >> 1; //Detect bit by bit, so move the data right by one bit
}
}
//the sign that data transmission ends
void IIC_end()
{
digitalWrite(SCL_Pin,LOW);
delayMicroseconds(3);
digitalWrite(SDA_Pin,LOW);
delayMicroseconds(3);
digitalWrite(SCL_Pin,HIGH);
delayMicroseconds(3);
digitalWrite(SDA_Pin,HIGH);
delayMicroseconds(3);
}//*********************************************************
Which lines can you not explain yourself?
the functions like pinmode, servopulse, MR_PWM, ML_ctrl, delay, servopin, digital write, 20-pulsewithd/1000, analogwrite, send_data. Not the actual lines, im sorry for the confusion
the functions like pinmode, servopulse, MR_PWM, ML_ctrl, delay, servopin, digital write, 20-pulsewithd/1000, analogwrite, send_data. Not the actual lines, im sorry for the confusion...
did you look in the documentation or should we do that for you?
pinmode
analogwrite
...
if you don't understand
#define MR_PWM 9 //define PWM control pin of A motor
then may be you need to learn C++
1 Like
Start here:
Sadly, we wont be learning c++ but our assignment is to understand this and explain the entire
I suggest you start by googling things like "arduino pinmode" and collect the explanations in maybe a printed page or print to pdf etc.
Also know the "Arduino Reference" is quite terse. For functional statements like "if", "for", "while" etc. you will be better served if you go to a C++ site as they usually have more detail.
Special functions are usually best described in their library documentation.
ok thanks, is there more like this?
non sequitur
For what course is this assignment? Can you post the exact assignment you were given?
The Arduino language reference is the source of explanations for all of the "Arduino" functions.
I like cplusplus.com for references to C++ functions.
you google "Arduino xxxx documentation" for each xxx keyword you don't understand, that should get you started at least for the functions
it won't help for 20-pulsewithd/1000... this is simple maths formula that you have to put in context
but if you don't understand the language I'm unsure what's the point trying to dissect the code...
yea but it would be great if someone could explain the/hardest functions with examples from my posted code
I think the keyword here is "our".
Can you mark-up the particular lines that are causing problems, and save us the effort of having to explain everything?
1 Like
yeah it would be great if someone would also write your essay about it and take tour final tests so that you don't have any work to do...
seems you are pretty lazy. The goal of the exercise if probably for you to dig into all this and learn from it....
good luck
PS/ I will be good and contribute a bit
the line
//*********************************************************
is a comment to make the text look good and can safely be ignored.
1 Like
we are building a arduino robot and our teacher gave us the assignment to "Your robot should run around without colliding with anything. In the event of obstacles, the robot must stop, check to the right and left and decide in which direction it should drive, turn in the direction it is most free and continue its journey in that direction. If it is not possible to drive either to the right or to the left, the robot must turn 180 degrees and continue its journey." after that we must explain the code
so why didn't you write the code. I think the exercice to explain the code is to ensure that you did not steal it from someone else or the internet...
seems this is what you did... (the */ at the start of the code seems to indicate you removed something that was before that, like copyright or credit to the author)
And your teacher did that without teaching you anything about C++?
If that is true, I get the feeling that this is a case for a review board, not for this forum, because it paints your teacher as quite incompetent. But I also get the feeling that it is not true.
1 Like
BTW - seen this post from 26 days ago
so code is coming from
https://wiki.keyestudio.com/KS0470_Keyestudio_4WD_BT_Robot_Car_V2.0_Kit_for_Arduino#Project_12:_Ultrasonic_Avoiding_Robot