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/*********************************************************************
 This is an example for our nRF51822 based Bluefruit LE modules
  
 Modified to drive a 3-wheeled BLE Robot Rover! by http://james.devi.to

 Pick one up today in the Adafruit shop!

 Adafruit invests time and resources providing this open source code,
 please support Adafruit and open-source hardware by purchasing
 products from Adafruit!

 MIT license, check LICENSE for more information
 All text above, and the splash screen below must be included in
 any redistribution
*********************************************************************/

#include <string.h>
#include <Arduino.h>
#include <SPI.h>
#if not defined (_VARIANT_ARDUINO_DUE_X_)
  #include <SoftwareSerial.h>
#endif

#include "Adafruit_BLE.h"
#include "Adafruit_BluefruitLE_SPI.h"
#include "Adafruit_BluefruitLE_UART.h"

#include "BluefruitConfig.h"

#include <Wire.h>
#include <Adafruit_MotorShield.h>
// #include "utility/Adafruit_PWMServoDriver.h"
// #include <Servo.h> 

// Create the motor shield object with the default I2C address
Adafruit_MotorShield AFMS = Adafruit_MotorShield(); 

// And connect 2 DC motors to port M3 & M4 !
Adafruit_DCMotor *L_MOTOR = AFMS.getMotor(4);
Adafruit_DCMotor *R_MOTOR = AFMS.getMotor(3);

//not used, testing acceleration
// int accelTime = 200;

//Name your RC here
String BROADCAST_NAME = "adafruit red robot rover";

String BROADCAST_CMD = String("AT+GAPDEVNAME=" + BROADCAST_NAME);

Adafruit_BluefruitLE_SPI ble(BLUEFRUIT_SPI_CS, BLUEFRUIT_SPI_IRQ, BLUEFRUIT_SPI_RST);


// A small helper
void error(const __FlashStringHelper*err) {
  Serial.println(err);
  while (1);
}

// function prototypes over in packetparser.cpp
uint8_t readPacket(Adafruit_BLE *ble, uint16_t timeout);
float parsefloat(uint8_t *buffer);
void printHex(const uint8_t * data, const uint32_t numBytes);

// the packet buffer
extern uint8_t packetbuffer[];

char buf[60];

/**************************************************************************/
/*!
    @brief  Sets up the HW an the BLE module (this function is called
            automatically on startup)
*/
/**************************************************************************/
void setup(void)
{
  Serial.begin(9600);

  AFMS.begin();  // create with the default frequency 1.6KHz

  // turn on motors
  L_MOTOR->setSpeed(0);
  L_MOTOR->run(RELEASE);

  R_MOTOR->setSpeed(0);
  R_MOTOR->run(RELEASE);
    
  Serial.begin(115200);
  Serial.println(F("Adafruit Bluefruit Robot Controller Example"));
  Serial.println(F("-----------------------------------------"));

  /* Initialize the module */
  BLEsetup();
  

}

int velocity = 0;

float x, y;

int L_restrict = 0;
int R_restrict = 0;

unsigned long lastAccelPacket = 0;

bool modeToggle = false;

void loop(void)
{
    // read new packet data
    uint8_t len = readPacket(&ble, BLE_READPACKET_TIMEOUT);
    // if (len == 0) return;

  // Read from Accelerometer input
    if( accelMode() ) {
      lastAccelPacket = millis();
      modeToggle = true;
      return;
    }

  // Stop motors if accelerometer data is turned off (100ms timeout)
    if( millis() - lastAccelPacket > 100 & modeToggle) {
      L_MOTOR->run(RELEASE);
      R_MOTOR->run(RELEASE);
      modeToggle = false;
      return;
    }

    //if no accelerometer, use control pad
    if( !modeToggle ) buttonMode();
    
}


bool accelMode(){
  if (packetbuffer[1] == 'A') {
          x = parsefloat( packetbuffer + 2 );
          y = parsefloat( packetbuffer + 6 );

        if( x <= -0.55 ){
          x += 0.55;
          x *= -100.0;
          L_MOTOR->run( BACKWARD );
          R_MOTOR->run( BACKWARD );
          if( x >= 45 ) x = 45;
          if( x <= 0 ) x = 0;
          velocity = map( x, 0, 45, 0 ,255 );
        }
        else if( x >= -0.25 ){
          x+= 0.25;
          x *= 100;
          L_MOTOR->run( FORWARD );
          R_MOTOR->run( FORWARD );
          if( x>= 45 ) x = 45;
          if( x<= 0 ) x = 0;
          velocity = map( x, 0, 45, 0, 255 );
        }
        else{
          L_MOTOR->run( RELEASE );
          R_MOTOR->run( RELEASE );
          velocity = 0;
        }

        //account for L / R accel

        if( y >= 0.1 ){
            y -= 0.1;
            y *= 100;
            if( y >= 50 ) y = 50;
            if( y <= 0 ) y = 0;

            L_restrict = fscale( y, 0.0, 50.0, 0.0, 100.0, -4.0 );
        }
        else if( y <= -0.1 ){
            y += 0.1;
            y *= -100;
            if( y>= 50 ) y = 50;
            if( y<= 0 ) y = 0;

            R_restrict = fscale( y, 0.0, 50.0, 0.0, 100.0, -4.0 );
        }
        else{
            L_restrict = 0;
            R_restrict = 0;
        }

          float Lpercent = ( 100.0 - L_restrict ) / 100.00 ;
          float Rpercent = ( 100.0 - R_restrict ) / 100.00 ;

          // Serial.print( x ); 
          // Serial.print( "\t" ); 
          // Serial.print( Lpercent ); 
          // Serial.print( "\t" ); 
          // Serial.print( velocity ); 
          // Serial.print( "\t" ); 
          // Serial.println( Rpercent ); 

          L_MOTOR->setSpeed( velocity * Lpercent ); 
          R_MOTOR->setSpeed( velocity * Rpercent ); 

          return true;
    }
    return false;
}

bool isMoving = false;

bool buttonMode(){

  static unsigned long lastPress = 0;
  

 // Buttons
  if (packetbuffer[1] == 'B') {

    uint8_t buttnum = packetbuffer[2] - '0';
    boolean pressed = packetbuffer[3] - '0';

    // Serial.println(buttnum);

  Serial.println(isMoving);
    if (pressed) {
      isMoving = true;
      if(buttnum == 5){
        L_MOTOR->run(FORWARD);
        R_MOTOR->run(FORWARD);
      }
      if(buttnum == 6){
        L_MOTOR->run(BACKWARD);
        R_MOTOR->run(BACKWARD);        
      }
      if(buttnum == 7){
        L_MOTOR->run(RELEASE);
        R_MOTOR->run(FORWARD);
      }
      if(buttnum == 8){
        L_MOTOR->run(FORWARD);
        R_MOTOR->run(RELEASE);        
      }

      lastPress = millis();
      
        L_MOTOR->setSpeed(255); 
        R_MOTOR->setSpeed(255);  
    } 

    else {
      isMoving = false;
      L_MOTOR->run(RELEASE);
      R_MOTOR->run(RELEASE);
    }
     return true; 
  }
    // if(isMoving){
      
      // unsigned long timeSincePress = millis() - lastPress;

      // if(timeSincePress <= accelTime){

      //   Serial.println( timeSincePress ) ;
        
      //   int motorSpeed = map( timeSincePress, 0, accelTime, 0, 255 );
        
      //   L_MOTOR->setSpeed(motorSpeed); 
      //   R_MOTOR->setSpeed(motorSpeed); 
      // }
      
      // else{
       // // full speed ahead!
        // L_MOTOR->setSpeed(255); 
        // R_MOTOR->setSpeed(255);  
      // }
   // }

  return false;

}

void BLEsetup(){
  Serial.print(F("Initialising the Bluefruit LE module: "));

  if ( !ble.begin(VERBOSE_MODE) )
  {
    error(F("Couldn't find Bluefruit, make sure it's in CoMmanD mode & check wiring?"));
  }
  Serial.println( F("OK!") );

  /* Perform a factory reset to make sure everything is in a known state */
  Serial.println(F("Performing a factory reset: "));
  if (! ble.factoryReset() ){
       error(F("Couldn't factory reset"));
  }

  //Convert the name change command to a char array
  BROADCAST_CMD.toCharArray(buf, 60);

  //Change the broadcast device name here!
  if(ble.sendCommandCheckOK(buf)){
    Serial.println("name changed");
  }
  delay(250);

  //reset to take effect
  if(ble.sendCommandCheckOK("ATZ")){
    Serial.println("resetting");
  }
  delay(250);

  //Confirm name change
  ble.sendCommandCheckOK("AT+GAPDEVNAME");

  /* Disable command echo from Bluefruit */
  ble.echo(false);

  Serial.println("Requesting Bluefruit info:");
  /* Print Bluefruit information */
  ble.info();

  Serial.println(F("Please use Adafruit Bluefruit LE app to connect in Controller mode"));
  Serial.println(F("Then activate/use the sensors, color picker, game controller, etc!"));
  Serial.println();

  ble.verbose(false);  // debug info is a little annoying after this point!

  /* Wait for connection */
  while (! ble.isConnected()) {
      delay(500);
  }

  Serial.println(F("*****************"));

  // Set Bluefruit to DATA mode
  Serial.println( F("Switching to DATA mode!") );
  ble.setMode(BLUEFRUIT_MODE_DATA);

  Serial.println(F("*****************"));
}

//Logarithmic mapping function from http://playground.arduino.cc/Main/Fscale
float fscale( float inputValue,  float originalMin, float originalMax, float newBegin, float newEnd, float curve){

  float OriginalRange = 0;
  float NewRange = 0;
  float zeroRefCurVal = 0;
  float normalizedCurVal = 0;
  float rangedValue = 0;
  boolean invFlag = 0;


  // condition curve parameter
  // limit range

  if (curve > 10) curve = 10;
  if (curve < -10) curve = -10;

  curve = (curve * -.1) ; // - invert and scale - this seems more intuitive - postive numbers give more weight to high end on output 
  curve = pow(10, curve); // convert linear scale into lograthimic exponent for other pow function

  /*
   Serial.println(curve * 100, DEC);   // multply by 100 to preserve resolution  
   Serial.println(); 
   */

  // Check for out of range inputValues
  if (inputValue < originalMin) {
    inputValue = originalMin;
  }
  if (inputValue > originalMax) {
    inputValue = originalMax;
  }

  // Zero Refference the values
  OriginalRange = originalMax - originalMin;

  if (newEnd > newBegin){ 
    NewRange = newEnd - newBegin;
  }
  else
  {
    NewRange = newBegin - newEnd; 
    invFlag = 1;
  }

  zeroRefCurVal = inputValue - originalMin;
  normalizedCurVal  =  zeroRefCurVal / OriginalRange;   // normalize to 0 - 1 float

  /*
  Serial.print(OriginalRange, DEC);  
   Serial.print("   ");  
   Serial.print(NewRange, DEC);  
   Serial.print("   ");  
   Serial.println(zeroRefCurVal, DEC);  
   Serial.println();  
   */

  // Check for originalMin > originalMax  - the math for all other cases i.e. negative numbers seems to work out fine 
  if (originalMin > originalMax ) {
    return 0;
  }

  if (invFlag == 0){
    rangedValue =  (pow(normalizedCurVal, curve) * NewRange) + newBegin;

  }
  else     // invert the ranges
  {   
    rangedValue =  newBegin - (pow(normalizedCurVal, curve) * NewRange); 
  }

  return rangedValue;
}
This guide was first published on Jan 06, 2016. It was last updated on Jan 06, 2016. This page (Code) was last updated on Jan 06, 2016.