Backport patches from arduino/ArduinoCore-mbed

[facchinm]

This should be the last maintenance release of this core; since this core is based on mbed 5.x branch all functions marked for deprecation are still there; arduino/ArduinoCore-mbed, on the other hand, contains all the new stuff and should replace this core as soon as considered stable.

Reworks and includes #31 and #72

[rmlearney-digicatapult]

Excited!

One note - interrupts.cpp still doesn't cover all possible interrupt types (HIGH, LOW) - is it better to have the irq setting as a switch(mode) rather than nested if/else tests so it can be extended in future?

[facchinm]

Ah sorry, I just spotted an error in my last rebase; working on it now
@rmlearney-digicatapult I misread your comment 🙂
mbed doesn't currently support level based interrupts https://github.com/arduino/ArduinoCore-nRF528x-mbedos/blob/beta/cores/arduino/mbed/hal/gpio_irq_api.h#L34-L38 but we can work on it with them. If you could open a separate issue it could be better to keep track of the request

[rmlearney-digicatapult]

@facchinm ah, if they're not supported then no worries. Thanks!

[rmlearney-digicatapult]

@facchinm this implementation in Interrupts.cpp doesn't seem to support CHANGE:

  // Give a default pullup for the pin, since calling InterruptIn with PinMode is impossible
   if (digitalPinToGpio(interruptNum) == NULL) {
     pinMode(interruptNum, mode == FALLING ? INPUT_PULLUP : INPUT_PULLDOWN);
   }

Perhaps the following?

   if (digitalPinToGpio(interruptNum) == NULL) {
     switch(mode){
       case FALLING:
         pinMode(interruptNum, INPUT_PULLUP);
         break;
       case RISING:
         pinMode(interruptNum, INPUT_PULLDOWN);
         break;
       case CHANGE:
         pinMode(interruptNum, INPUT);
         break;
       default:
         pinMode(interruptNum, INPUT);
         break;
     }
   }

[facchinm]

@rmlearney-digicatapult the snippet you are linking only applies is the pin has not been configured as INPUT before calling attachInterrupt . If you look at the beta branch, the implementation on CHANGE is correct https://github.com/arduino/ArduinoCore-nRF528x-mbedos/blob/beta/cores/arduino/Interrupts.cpp#L39-L48

[rmlearney-digicatapult]

What will be the default pin state if somebody doesn't configure the pin as INPUT but calls an attachInterrupt on CHANGE?

Won't it be pulled down according to this code, which means it won't trigger properly?

[facchinm]

Yep, you are right! Would you mind sending a PR over beta branch with the commit to fix it (so we can keep the attribution) ? Thanks