Porting Interrupts

[Fyod]

I'm having problems trying to get interrupts made for AVR working on the Teensy.

This is the part of the code that's giving me trouble

#define PIN_MASK     0b00001100

void NazaDecoderLib::startPwmReader()
{
  pinMode(2, INPUT_PULLUP); // Pitch (Arduino D2 <-> Naza F2)
  pinMode(1, INPUT_PULLUP); // Roll  (Arduino D3 <-> Naza F1)
  cli();
  PCICR = 1 << PCIE2;
  PCMSK2 = PIN_MASK;
  sei();
}

void NazaDecoderLib::pwmInterruptHandler()
{
  uint8_t bit;
  uint8_t curr;
  uint8_t mask;
  uint32_t currentTime;
  uint32_t time;

  // get the pin states for the indicated port.
  curr = PIND & PIN_MASK;
  mask = curr ^ pcIntLast;
  pcIntLast = curr;

  currentTime = micros();

  // mask is pcint pins that have changed.
  for (uint8_t i = 0; i < 2; i++) {
    bit = 0b00000100 << i;
    if (bit & mask) {
      // for each pin changed, record time of change
      if (bit & pcIntLast) {
        time = currentTime - pwmData[i].fallTime;
        pwmData[i].riseTime = currentTime;
        if ((time >= 10000) && (time <= 26000))
          pwmData[i].edge = 1;
        else
          pwmData[i].edge = 0; // invalid rising edge detected
      }
      else {
        time = currentTime - pwmData[i].riseTime;
        pwmData[i].fallTime = currentTime;
        if ((time >= 800) && (time <= 2200) && (pwmData[i].edge == 1)) {
          pwmData[i].lastGoodWidth = time;
          pwmData[i].edge = 0;
        }
      }
    }
  }
}

ISR(PCINT2_vect)
{
  NazaDecoder.pwmInterruptHandler();
}

I get

NazaDecoderLib.cpp: In member function 'void NazaDecoderLib::startPwmReader()':
NazaDecoderLib.cpp:139:3: error: 'PCICR' was not declared in this scope
NazaDecoderLib.cpp:139:16: error: 'PCIE2' was not declared in this scope
NazaDecoderLib.cpp:140:3: error: 'PCMSK2' was not declared in this scope
NazaDecoderLib.cpp: At global scope:
NazaDecoderLib.cpp:184:4: error: expected constructor, destructor, or type conversion before '(' token

I have tried #include avr/io.h and interrupt.h, but that doesn't do anything. Interrupt.h is empty.
Not sure what to do next. The http://www.pjrc.com/teensy/interrupts.html info has the PCICR etc. names, but I'm not sure what to do with them, so I'm stuck.

 

[PaulStoffregen]

On Teensy 3.1, all the pins have interrupt capability. You can probably just delete the AVR pin change code and use attachInterrupt.

For example:

void NazaDecoderLib::startPwmReader()
{
  pinMode(2, PCINT2_vect, INPUT_PULLUP); // Pitch (Arduino D2 <-> Naza F2)
  pinMode(1, PCINT2_vect, INPUT_PULLUP); // Roll  (Arduino D3 <-> Naza F1)   // is pin 1 a bug?
  attachInterrupt(2, CHANGE);
  attachInterrupt(3, CHANGE);
}

Change the interrupt handler to a normal function, like this:

void PCINT2_vect(void) {
{
  NazaDecoder.pwmInterruptHandler();
}

Or if you can cause NazaDecoder.pwmInterruptHandler to be a static function, it could be called directly from attachInterrupt. But attachInterrupt can't call non-static C++ functions.

Also, you'll probably need to change that pinMode() line to configure the correct pin.

 

[Fyod]

Thanks, Paul! That is basically what I thought at first, but then I started overthinking it.
Can't wait to try it out.