Please help: Stepper Motor via Bluetooth

Using Arduino Programming Questions
1

Hi, I am attempting to communicate commands for my stepper motors from my android to my arduino via Bluetooth H05. I am able to pass the commands through but I can not figure out why the command does not follow through the rest of the code to the "lastcall" so instead of having the stepper motor continuously running on the last command I typed in it would just execute once and stop. Please let me know what is wrong with the code. Thanks!

#include <Stepper.h>
#include <SoftwareSerial.h>

SoftwareSerial EEBlue(10, 11); // RX | TX

//definitions for each command to be recieved via serial port
#define COMMAND_LEFT 'l'
#define COMMAND_RIGHT 'r'
#define COMMAND_FORWARD 'u'
#define COMMAND_BACK 'd'
#define COMMAND_STOP 's'

//enter the steps per rev for your motors here
int stepsInRev = 200;

//this sets the value for the for loops and therefore sets the amount of steps in each call
int num_of_steps = 1;
// setup pins for each driver motor1 ~ IN1, IN2, IN3, IN4; motor2 ~ IN1, IN2, IN3, IN4
Stepper myStepper1(stepsInRev, 5, 4, 3, 2);
Stepper myStepper2(stepsInRev, 9, 8, 7, 6);
// variable to store the last call to the serial port
char lastCall = ' ';

//to move the motors forward
void forwardStep(int steps){
  Serial.println("forward");
  // step one step each forward
  myStepper1.step(1);
  myStepper2.step(1);
  delay(2);
}

// to move the motors back
void backwardStep(int steps){
  Serial.println("backward");
  // step one step each backward
  myStepper1.step(-1);
  myStepper2.step(-1);
  delay(2);
}
 

// to move the motors in opposite directions (left)
void leftStep(int steps){
  Serial.println("left");
 // step one step each left
  myStepper1.step(1);
  myStepper2.step(-1);
  delay(2);
}


// to move the motors in opposite directions (right)
void rightStep(int steps){
  Serial.println("right");
  // step one step each right
  myStepper1.step(-1);
  myStepper2.step(1);
  delay(2); 
}

// to power down the motor drivers and stop the motors
void allStop(){
  Serial.println("stop");
  // steppers stop
  PORTD = B00000000; //sets all of the pins 0 to 7 as LOW to power off stepper1
  PORTB = B00000000; //sets all of the pins 8 to 13 as LOW to power off stepper2
}
void setup() {
  Serial.begin(9600);//start the bluetooth serial port - send and recieve at 9600 baud
   EEBlue.begin(9600);
  // set the speed at 60 rpm:
  myStepper1.setSpeed(600);
  myStepper2.setSpeed(600);
}

void loop() {
//check to see if there is serial communication and if so read the data
if(EEBlue.available())
{
char data = (char)EEBlue.read();

// switch to set the char via serial to a command
switch(data) {
  case COMMAND_FORWARD:
    forwardStep(num_of_steps);
    break; 
  case COMMAND_BACK:
    backwardStep(num_of_steps);
    break;
  case COMMAND_LEFT:
    leftStep(num_of_steps);
    break;
  case COMMAND_RIGHT:
    rightStep(num_of_steps);
    break;
  case COMMAND_STOP:
    allStop();
    break;
}
// set the 'lastCall' variable to the last call from the serial
lastCall = data;
}
else{
char data = lastCall;
switch(data) {
  case COMMAND_FORWARD:
    forwardStep(num_of_steps);
    break; 
  case COMMAND_BACK:
    backwardStep(num_of_steps);
    break;
  case COMMAND_LEFT:
    leftStep(num_of_steps);
    break;
  case COMMAND_RIGHT:
    rightStep(num_of_steps);
    break;
  case COMMAND_STOP:
    allStop();
    break;
}
lastCall = data;
}
}
2

I think this will do the same job and it's a lot shorter

void loop() {
 //check to see if there is serial communication and if so read the data
 if(EEBlue.available())
 {
 lastCall = (char)EEBlue.read();
 }
 
 // switch to set the char via serial to a command
 switch(lastCall) {
  case COMMAND_FORWARD:
 forwardStep(num_of_steps);
 break; 
  case COMMAND_BACK:
 backwardStep(num_of_steps);
 break;
  case COMMAND_LEFT:
 leftStep(num_of_steps);
 break;
  case COMMAND_RIGHT:
 rightStep(num_of_steps);
 break;
  case COMMAND_STOP:
 allStop();
 break;
 }
}

You don't have any print statements to allow you to see what value is in the different variables or to trace the flow of the program.

Also the way you are getting the Bluetooth data is not robust. Have a look at the examples in Serial Input Basics - simple reliable ways to receive data.

And there is this clever idea if you just want to check for single characters.

...R