BlinkyTape Interrupt Example

gistfile1.txt

#include <FastSPI_LED2.h>

#define DEBUG

#define LED_COUNT 60 // BlinkyTape has 60 LEDs!
struct CRGB leds[LED_COUNT]; // this struct contains 60 CRGB values.  This is where 
#define LED_MAX_BRIGHTNESS 55

#define PIN_BUTTON 10
#define PIN_IO_A   7
#define PIN_IO_B   11
#define PIN_SIGNAL 13
#define PIN_INPUT  10

const int debounceTime = 20;  // debounce in milliseconds
volatile boolean button_pressed;    // set when button pressed from withing the ISR for the main loop to action on
byte light_status; //to toggle the led colors when button is pressed, need to remember previous status

inline void deBounce () //try inline
{
  unsigned long now = millis ();
  do
  {
    // on bounce, reset time-out
    if ((PINB & (1<<PINB6)) == LOW)
      now = millis ();
  } 
  while ((PINB & (1<<PINB6)) == LOW ||
    (millis () - now) <= debounceTime);

}  // end of deBounce


void wait (unsigned int wait_time) // wait time in milli seconds
{

  unsigned int time_end=millis()+wait_time;
  unsigned int time_now=0;
  while (time_end>millis() ){
  }
}

void buttonDown ()                            
{
  if( digitalRead(PIN_BUTTON) == LOW)
        { 
      button_pressed = true;
        }
}  // end of buttonDown


ISR(PCINT0_vect) // PCINT0 ISR
{
 // byte saveSREG = SREG; // Save SREG
 // noInterrupts();       // disable interrupts shouldn't be necessary as we use  PCINT0_vect with
                          // no attribute = ISR_BLOCK. other options requiring this are ISR_NOBLOCK, ISR_NAKED
   if ((PINB & (1<<PINB6)) == LOW){
      button_pressed=true;  // set flag to indicate BUTTON Pushed
   }
 // SREG = saveSREG;     // restore SREG
 // interrupts();        //not necessary with this ISR call
}

void setup()
{  
// Serial.begin(9600);
  Serial.begin(115200);
 #ifdef DEBUG 
      Serial.println("Entering setup()" ); 
 #endif 
 
  LEDS.addLeds<WS2811, PIN_SIGNAL, GRB>(leds, LED_COUNT); // this configures the BlinkyBoard - leave as is.
  LEDS.showColor(CRGB(0, 0, 0)); // set the color for the strip all at once.
  LEDS.setBrightness(50); // start out with LEDs at 50
#ifdef DEBUG    
  wait (2000);
  LEDS.showColor(CRGB(100, 100, 100));
  light_status=true;
  wait (2000);
 #endif
 
#ifdef DEBUG 
      Serial.println("Setting up button interruption)" ); 
 #endif 
 // works very well tested ok
 // Setup for test using low level registers
    EIFR = 4;      // cancel any existing falling interrupt 4 to avoid entering immediately into the interrupt once attached
  
    DDRB &= ~(1 << DDB6); // Clear the PB6 pin
    // PB6 is now an input

    PORTB |= (1 << PORTB6); // turn On the Pull-up
    // PB6 is now an input with pull-up enabled
    //PCICR = PCIE0 = Bit0,  
    PCICR |= (1 << PCIE0);    // set PCIE0 to enable PCMSK0 scan
    PCMSK0 |= (1 << PCINT6);  // set PCINT0 to trigger an interrupt on state change of D10/PCINT6
// End setup for test using low level registers

/* uncomment this section if you want to test with standard arduino functions and comment out the previous low lever register section
// Setup for test using "standard" arduino functions, not as responsive as the low level register coding
   EIFR=4; // cancel any existing falling interrupt 4 to avoid entering immediately into the interrupt once attached
   pinMode(PIN_BUTTON, INPUT_PULLUP);
   attachInterrupt (4, buttonDown, FALLING);   // ready for button press. is it interrupt 4 for change pin status, interested in the press
// End Setup for test using "standard" arduinio functions
*/

 #ifdef DEBUG 
      Serial.println("End button interruption setup" ); 
 #endif

#ifdef DEBUG
Serial.println ("End Setup");
#endif
}

uint8_t button_state;
uint8_t last_button_state = 0;
uint8_t color_b = 0;

void loop() {

 // Test using the button digitalread in the main loops works well 
/*
#ifdef DEBUG
Serial.print ("in Loop. "); Serial.print ("Checking if the button is pressed in the loop");
#endif

#ifdef DEBUG
Serial.println ("Reading PIN_BUTTON (not interrupt)");
#endif

 button_state = digitalRead(PIN_BUTTON);
  if((button_state != last_button_state) && (button_state == LOW)) {
     #ifdef DEBUG
      Serial.print("PIN_BUTTON pressed button_state = ");Serial.print(button_state);Serial.println(" calling Debounce()");
      #endif
      deBounce ();
      #ifdef DEBUG
      Serial.print("Turning on the lights 1/2 blue, color_b = ");Serial.println (color_b);
      #endif
        LEDS.showColor(CRGB(0, 0, color_b));
        color_b +=50;
  }
      
  last_button_state = button_state;
*/
  
#ifdef DEBUG
Serial.print ("in Loop. Testing interrupt "); Serial.print ("button_pressed = "); Serial.println (button_pressed);
#endif


  if (button_pressed)
    {
      #ifdef DEBUG
      Serial.println("Button pressed, calling deBounce()");
      #endif
      deBounce ();
      button_pressed = false;
      #ifdef DEBUG
      Serial.print("light_status =");Serial.println(light_status);
      #endif
      if (light_status) {
        #ifdef DEBUG
      Serial.print("light_status =");Serial.print(light_status);Serial.println(" turning on the lights red, light_status = false");
      #endif
        LEDS.showColor(CRGB(255, 0, 0));
        light_status=false;
      } else {
        #ifdef DEBUG
      Serial.print("light_status =");Serial.print(light_status);Serial.println(" turning on the lights green, light_status = true");
      #endif
         LEDS.showColor(CRGB(0, 255, 0));
         light_status=true;
      }
    }   
wait (750); 
// testing something additional
Serial.println("calling ASM NOP");
 __asm__("nop\n\t"); 
Serial.println("returned from ASM NOP");

/* #ifdef DEBUG
 Serial.println ("Bottom of Loop. after Testing interrupt code "); 
#endif
*/

}