RC Car Control Receiver with simple 433MHz modules

gistfile1.pde

// receiver.pde
//
// Simple example of how to use VirtualWire to receive messages
// Implements a simplex (one-way) receiver with an Rx-B1 module
//
// See VirtualWire.h for detailed API docs
// Author: Mike McCauley ([email protected])
// Copyright (C) 2008 Mike McCauley
// $Id: receiver.pde,v 1.3 2009/03/30 00:07:24 mikem Exp $

#include <VirtualWire.h>
#include <AFMotor.h>
 
AF_DCMotor motor1(1, MOTOR12_1KHZ); // create motor #1, 1KHz pwm
AF_DCMotor motor2(2, MOTOR12_1KHZ); // create motor #2, 1KHz pwm
AF_DCMotor motor3(3, MOTOR34_1KHZ); // create motor #3, 1KHz pwm
AF_DCMotor motor4(4, MOTOR34_1KHZ); // create motor #4, 1KHz pwm

const int X_THRESHOLD_LOW = 505;
const int X_THRESHOLD_HIGH = 530;    

const int Y_THRESHOLD_LOW = 500;
const int Y_THRESHOLD_HIGH = 510;    

int x_position;
int y_position;

int x_direction;
int y_direction;

int current_x_direction;
int current_y_direction;

uint8_t motor1_speed;
uint8_t motor2_speed;
uint8_t motor3_speed;
uint8_t motor4_speed;

void setup()
{
    Serial.begin(9600);	// Debugging only
    Serial.println("setup");

    motor1_speed = 255;
    motor2_speed = 255;
    motor3_speed = 255;
    motor4_speed = 255;

    motor1.setSpeed(0);     // set the speed to 200/255
    motor2.setSpeed(0);     // set the speed to 200/255
    motor3.setSpeed(0);     // set the speed to 200/255
    motor4.setSpeed(0);     // set the speed to 200/255

    motor1.run(RELEASE);      // turn it on going backwards
    motor2.run(RELEASE);      // turn it on going backwards
    motor3.run(RELEASE);      // turn it on going backwards
    motor4.run(RELEASE);      // turn it on going backwards         

    // Due to lack of access to Digital Pins with Motor Shield in place, using Analogue A0 (Arduino Pin 14) as Digital
    vw_set_rx_pin(14);
    
    // Initialise the IO and ISR
    vw_set_ptt_inverted(true); // Required for DR3100
    vw_setup(2000);	 // Bits per sec

    vw_rx_start();       // Start the receiver PLL running

    current_x_direction = 0;
    current_y_direction = 0;
    x_direction = 0;
    y_direction = 0;
    Serial.println("setup done");
}

void loop()
{
    uint8_t buf[VW_MAX_MESSAGE_LEN];
    uint8_t buflen = VW_MAX_MESSAGE_LEN;

    if (vw_get_message(buf, &buflen)) // Non-blocking
    {
        int i;
      	int j;
 

        digitalWrite(13, true); // Flash a light to show received good message
	// Message with a good checksum received, dump it.
	Serial.print("Got: ");
	
	for (i = 0; i < buflen; i++)
	{
	    Serial.print(buf[i], HEX);
	    Serial.print(" ");
	}
	Serial.println("");
        digitalWrite(13, false);

      // Format is XnnnnYnnnnAnBnCnDn
      // X is X position of joystick as 4 digits
      // Y is Y position of joystick as 4 digits
      // A is A button on joystick. 0= Not pressed. 1 = pressed
      // B is B button on joystick. 0= Not pressed. 1 = pressed
      // C is C button on joystick. 0= Not pressed. 1 = pressed
      // D is D button on joystick. 0= Not pressed. 1 = pressed

      //Serial.println("");

      x_position = (1000 * (buf[1] - 48)) + (100*(buf[2] - 48)) + (10*(buf[3] - 48)) + (buf[4] - 48);
      y_position = (1000 * (buf[6] - 48)) + (100*(buf[7] - 48)) + (10*(buf[8] - 48)) + (buf[9] - 48);

      Serial.println(x_position);
      Serial.println(y_position);
  
      // Forwards
      if (y_position > 600){
        y_direction = 1;
      }
      // Backwards
      else if (y_position < 400){
        y_direction = -1;
      }
      // Stop
      else {
        y_direction = 0;
      }
      
      // Now sort out turning
      // Right Forwards
      if ((x_position > 600) && (y_direction == 1)){
        x_direction = 1;
        motor1_speed = 125;
        motor2_speed = 255;
        motor3_speed = 255;
        motor4_speed = 125;
        Serial.println("Right Forwards");
      }
      // Left Forwards
      else if ((x_position < 400) && (y_direction == 1)){
        x_direction = -1;
        motor1_speed = 255;
        motor2_speed = 125;
        motor3_speed = 125;
        motor4_speed = 255;
        Serial.println("Left Forwards");
      }
      // Straight Forwards
      else if ((x_position > 400) && (x_position < 600) && (y_direction == 1)){
        x_direction = 0;
        motor1_speed = 255;
        motor2_speed = 255;
        motor3_speed = 255;
        motor4_speed = 255;
        Serial.println("Straight Forwards");
      }

      // Right Backwards
      else if ((x_position > 600) && (y_direction == -1)){
        x_direction = 1;
        motor1_speed = 255;
        motor2_speed = 125;
        motor3_speed = 125;
        motor4_speed = 255;
        Serial.println("Right Backwards");
      }
      // Left Backwards
      else if ((x_position < 400)  && (y_direction == -1)){
        x_direction = -1;
        motor1_speed = 125;
        motor2_speed = 255;
        motor3_speed = 255;
        motor4_speed = 125;
        Serial.println("Left Backwards");
      }
      // Straight Backwards
      else if ((x_position > 400) && (x_position < 600) && (y_direction == -1)){
        x_direction = 0;
        motor1_speed = 255;
        motor2_speed = 255;
        motor3_speed = 255;
        motor4_speed = 255;
        Serial.println("Straight Backwards");
      }
      // Stop
      else {
        x_direction = 0;
        motor1_speed = 0;
        motor2_speed = 0;
        motor3_speed = 0;
        motor4_speed = 0;
        Serial.println("Stop");
      }
      


      if ((y_direction == 1) && (current_y_direction == 1)){
          Serial.println("Still Forwards");
          motor1.setSpeed(motor1_speed);     
          motor2.setSpeed(motor2_speed);     
          motor3.setSpeed(motor3_speed);     
          motor4.setSpeed(motor4_speed);     
      }
      if ((y_direction == -1) && (current_y_direction == -1)){
          Serial.println("Still Backwards");
          motor1.setSpeed(motor1_speed);     
          motor2.setSpeed(motor2_speed);     
          motor3.setSpeed(motor3_speed);     
          motor4.setSpeed(motor4_speed);     
      }
      else if ((y_direction == -1) && ((current_y_direction == 1) || (current_y_direction == 0))){
          current_y_direction = -1;

          motor1.setSpeed(motor1_speed);     
          motor2.setSpeed(motor2_speed);     
          motor3.setSpeed(motor3_speed);     
          motor4.setSpeed(motor4_speed);     

          motor1.run(BACKWARD);      // turn it on going backwards
          motor2.run(BACKWARD);      // turn it on going backwards
          motor3.run(BACKWARD);      // turn it on going backwards
          motor4.run(BACKWARD);      // turn it on going backwards
          
          Serial.println("Newly Backwards");
      }
      else if ((y_direction == 1) && ((current_y_direction == -1) || (current_y_direction == 0))){
          current_y_direction = 1;

          motor1.setSpeed(motor1_speed);     
          motor2.setSpeed(motor2_speed);     
          motor3.setSpeed(motor3_speed);     
          motor4.setSpeed(motor4_speed);     

          motor1.run(FORWARD);      // turn it on going forwards
          motor2.run(FORWARD);      // turn it on going forwards
          motor3.run(FORWARD);      // turn it on going forwards
          motor4.run(FORWARD);      // turn it on going forwards
          
          Serial.println("Newly Forwards");
      }
      else if (y_direction == 0){
          current_y_direction = 0;
          motor1.run(RELEASE);      // turn it on going backwards
          motor2.run(RELEASE);      // turn it on going backwards
          motor3.run(RELEASE);      // turn it on going backwards
          motor4.run(RELEASE);      // turn it on going backwards         
          Serial.println("Stop");
      }
   }
}