delete PwmOut object crashes application

14 Aug 2015


I originally posted this as a question but didn't get a reply, so I did some more checking and I'm pretty sure this is a bug.

I'm using the nRF51822-DK platform, and wanted to delete, or shutdown, PwmOut objects during sleep, as they use a bit of background power.

The app kept crashing so I've created a simple app to test, and yep it crashes after 2 cycles

/* testing power consumption 
    PwmOut dynamic allocation not working
#include "mbed.h"

int main() {
    PwmOut *ptr;
    while(1) {
        ptr = new PwmOut(LED1);
        delete ptr;        

LED flashes twice then program goes nuts, all LEDs blink randomly. I'm assuming this object supports dynamic allocation, since I've read in many other posts people wanted to delete objects to save power. I also think the object is not deleting correctly, and after a quick look in src, found that there's no desctructor for this object, but not sure if that's normal, and tbh am a little cautious about changing something after just a quick inspection.

Looking forward to suggestions or comments

Thanks in advance Andrew

14 Aug 2015

This is something to check. Looks like there's no destructor defined for PwmOut but in the hal there's pwm free function. I wonder why it crashes. When I get a chance, I will look at this.

18 Aug 2015

Thanks Martin,