### Project 15  final fully functional project

**Test Code**

```
/*
 keyestudio Mini Tank Robot v2.0
 lesson 15
 bluetooth tank
 http://www.keyestudio.com
*/

//Array, used to store the data of pattern, can be calculated by yourself or obtained from the modulus tool
unsigned char start01[] = {0x01,0x02,0x04,0x08,0x10,0x20,0x40,0x80,0x80,0x40,0x20,0x10,0x08,0x04,0x02,0x01};
unsigned char front[] = {0x00,0x00,0x00,0x00,0x00,0x24,0x12,0x09,0x12,0x24,0x00,0x00,0x00,0x00,0x00,0x00};
unsigned char back[] = {0x00,0x00,0x00,0x00,0x00,0x24,0x48,0x90,0x48,0x24,0x00,0x00,0x00,0x00,0x00,0x00};
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 13  //define direction control pin of left motor
#define ML_PWM 11   //define PWM control pin of left motor
#define MR_Ctrl 12  //define direction control pin of right motor
#define MR_PWM 3    //define PWM control pin of right motor

char bluetooth_val; //save the value of Bluetooth reception

void setup()
{
  Serial.begin(9600);
  
  pinMode(SCL_Pin,OUTPUT);
  pinMode(SDA_Pin,OUTPUT);
  matrix_display(clear);    //Clear the display
  matrix_display(start01);  //display start pattern

  pinMode(ML_Ctrl, OUTPUT);
  pinMode(ML_PWM, OUTPUT);
  pinMode(MR_Ctrl, OUTPUT);
  pinMode(MR_PWM, OUTPUT);
}

void loop()
{
  if (Serial.available())
  {
    bluetooth_val = Serial.read();
    Serial.println(bluetooth_val);
  }
  switch (bluetooth_val) 
  {
     case 'F':  //forward command
        Car_front();
        matrix_display(front);  // show forward design
        break;
     case 'B':  //Back command
        Car_back();
        matrix_display(back);  //show back pattern
        break;
     case 'L':  // left-turning instruction
        Car_left();
        matrix_display(left);  //show “left-turning” sign 
        break;
     case 'R':  //right-turning instruction
        Car_right();
        matrix_display(right);  //display right-turning sign      
        break;
     case 'S':  //stop command
        Car_Stop();
        matrix_display(STOP01);  //show stop picture
        break;
  }
}

/**************The function of dot matrix****************/
//this function is used for dot matrix display
void matrix_display(unsigned char matrix_value[])
{
  IIC_start();
  IIC_send(0xc0);  //Choose address
  
  for(int i = 0;i < 16;i++) //pattern data has 16 bits
  {
     IIC_send(matrix_value[i]); //data to convey patterns
  }
  IIC_end();   //end to convey data pattern
  
  IIC_start();
  IIC_send(0x8A);  //display control, set pulse width to 4/16
  IIC_end();
}
//The condition starting to transmit data
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++)  //Each byte has 8 bits
  {
      digitalWrite(SCL_Pin,LOW);  //pull down clock pin SCL Pin to change the signals of SDA      
      delayMicroseconds(3);
      if(send_data & 0x01)  //set high and low level of SDA_Pin according to 1 or 0 of every bit
      {
        digitalWrite(SDA_Pin,HIGH);
      }
      else
      {
        digitalWrite(SDA_Pin,LOW);
      }
      delayMicroseconds(3);
      digitalWrite(SCL_Pin,HIGH); //pull up clock pin SCL_Pin to stop transmitting data
      delayMicroseconds(3);
      send_data = send_data >> 1;  // Detect bit by bit, so move the data right by one
  }
}
//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);
}
/*************the function to run motor**************/
void Car_front()
{
  digitalWrite(MR_Ctrl,LOW);
  analogWrite(MR_PWM,200);
  digitalWrite(ML_Ctrl,LOW);
  analogWrite(ML_PWM,200);
}
void Car_back()
{
  digitalWrite(MR_Ctrl,HIGH);
  analogWrite(MR_PWM,200);
  digitalWrite(ML_Ctrl,HIGH);
  analogWrite(ML_PWM,200);
}
void Car_left()
{
  digitalWrite(MR_Ctrl,LOW);
  analogWrite(MR_PWM,255);
  digitalWrite(ML_Ctrl,HIGH);
  analogWrite(ML_PWM,255);
}
void Car_right()
{
  digitalWrite(MR_Ctrl,HIGH);
  analogWrite(MR_PWM,255);
  digitalWrite(ML_Ctrl,LOW);
  analogWrite(ML_PWM,255);
}
void Car_Stop()
{
  digitalWrite(MR_Ctrl,LOW);
  analogWrite(MR_PWM,0);
  digitalWrite(ML_Ctrl,LOW);
  analogWrite(ML_PWM,0);
}
void Car_T_left()
{
  digitalWrite(MR_Ctrl,LOW);
  analogWrite(MR_PWM,255);
  digitalWrite(ML_Ctrl,LOW);
  analogWrite(ML_PWM,180);
}
void Car_T_right()
{
  digitalWrite(MR_Ctrl,LOW);
  analogWrite(MR_PWM,180);
  digitalWrite(ML_Ctrl,LOW);
  analogWrite(ML_PWM,255);
}
```

**Test Result**

<span style="color: rgb(255, 76, 65);">Note: </span>Remove the Bluetooth module before uploading test code. Otherwise, you will fail to upload test code. Reconnect Bluetooth module after uploading test code

Upload test code successfully, insert Bluetooth module, power on, and connect to Bluetooth. The tank robot can show distinct function by App.

Alright, the whole projects are finished. Please feel free to contact us if you confront some problems.