[SOLVED] latest git-snapshot causes freezes

[Yveaux]

@cimba007 Well, I filed (https://github.com/mysensors/MySensors/issues/598) and fixed (https://github.com/mysensors/MySensors/pull/599) and issue with interrupts not being detached correctly in all cases when using hwSleep().
This might be causing your issue, but is hard to say without actually debugging the code.
Once the PR is merged, could you try getting the latest development branch and see if it fixes the issue? (please use the development branch, without any local modifications)

[cimba007]

Just copy'pasted your fix and .. voila

Problems seems to be solved - although I do not unterstand why?!

• _wakeUp2Interrupt should be totally unrelated as it is never set
• detach should happen in the ISR

.. even if the interrupt is not detached correctly .. how should it lead to the total skip of these code:

	cli();
	wdt_reset();
	// enable WDT changes
	WDTCSR |= (1 << WDCE) | (1 << WDE);
	// restore saved WDT settings
	WDTCSR = WDTsave;
	Serial.println("sei()");
	Serial.flush();
	sei();
	// enable ADC
	ADCSRA |= (1 << ADEN);
	//WDTCSR |= (1 << WDIE); // set the WDIE flag to enable interrupt callback function.

As this code-snipped is skipped sei() gets never called in my case .. and the subsequent call to i2c freezes the node ... as i2c depends on interrupts ..

Anyway thanks Yveaux .. althour your fix is simple .. i don't know why it is working ...

EDIT: Furthermore .. even if the interrupt is not detached in the isr .. there should be no further interrupt if the interrupt register is not read via i2c .. and that in fact doesn't happen >:>

[Yveaux]

@cimba007 Great to hear it solves your problem!

Regarding the serial print not showing: you call it from withing a section with interrupts disabled; I don't know if this will work at all, or maybe even cause a hang... I would toggle some IO pins instead and use an oscilloscope to verify program flow.

Sleeping an AVR using the watchdog and pin interrupts is some tricky stuff, which is very susceptible to race conditions and almost impossible to debug without a decent hardware debugger.
Having a compiler that woes every now and then also isn't helping...

[cimba007]

I only used the pin change interrupt in another sketch. I was doubting Serial in sections without isr too! But they are clever. Serial output depends on polling in sections where interrupts are disabled ;-)

[Yveaux]

@cimba007 said:

Serial output depends on polling in sections where interrupts are disabled

Ok, learned something today ;-)

The PR has now been merged to development btw.

[cimba007]

@Yveaux While we are at this topic .. any chance to let the user-code know what caused the wakeup during sleep() ??

For example .. if there was a wakeup at all or which of the two interrupt sources was the cause.

Unforunatly the "cause" gets cleaned up at the end of hwSleep:

bool interruptWakeUp()
{
    return _wokeUpByInterrupt != INVALID_INTERRUPT_NUM;
}

Calling this from user-code will always return 0 as the end of hwSleep does this:

 _wokeUpByInterrupt = INVALID_INTERRUPT_NUM;

Not clearing the "last interrupt source" would be nice.

[tekka]

@cimba007 The return value of sleep() indicates the wake-up cause: irq (nr) or timer (=MY_WAKE_UP_BY_TIMER).
See here: https://github.com/mysensors/MySensors/blob/development/core/MyHwATMega328.cpp#L146-L147

[ikkeT]

I also confirm it fixed my problem. Thank you!

[cimba007]

@tekka Thanks, that is what I was looking for

[chrille]

@Yveaux Thank you for committing this fix. I had the same issue and it caused me a lot of headache