Disable interrupt within interrupt

Mbed OS
1

I am having issues with this interrupt, when it is called it keeps recalling and getting stuck in itself
therefor i think disabling from within would be the only solution i can think of. any ideas of how to do this?

image
image793×633 31.8 KB

2

Hello Jack,

Try to disable it by detaching the callback:

void callback() {
    device.attach(NULL);  // detach the callback
   ...
}

Then re-attach it as follows:

while (1) {
    if (global) {
        ...
        device.attach(&callback);
    }
....

Try to publish your code here as formatted text by prepending and appending it with three back-tick characters ``` on a separate line. It will enable people to copy & paste and modify it. A picture does not allow that.

Best regards, Zoltan

3

Hi Zoltan thanks for the advice however it throws the same error so am unsure how to solve this is the interrupt cannot be solved within itself.

#include "mbed.h"

Serial device(PC_12, PD_2);

bool global = 0;
int holding;

void callback() {
    global = 1;
    device.attach(NULL);
}

int main() {

    device.attach(&callback);

    while(1){
        if(global){
            char read[4];
            uint32_t hold = 0;
            device.gets(read,4);
            hold = (read[3]<<24)+(read[2]<<16)+(read[1]<<8)+read[0];
            printf("%X",hold);
            global = 0;
            device.attach(&callback);
        }
        wait(0.5);
        printf("waiting\r\n");
    }
}

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image801×175 6.26 KB

4

Hi there,

look at this, maybe it will help.

BR, Jan

5

Hello Jack,

Because Mbed OS 6 doesn’t allow to use the device in ISR context one option is to use EventQueue rather than ISR. To save RAM you can try to use application’s shared event queue:

#include "mbed.h"

BufferedSerial  device(PC_12, PD_2);
EventQueue*     eventQueue;
volatile bool   global = 0;
int             holding;

void callback()
{
    device.attach(NULL);
    global = 1;
}

int main()
{
    eventQueue = mbed_event_queue();
    device.attach(eventQueue->event(callback), BufferedSerial::RxIrq);

    while (1) {
        if (global) {
            char        read[4];
            uint32_t    hold = 0;
            device.gets(read, 4);
            hold = (read[3] << 24) + (read[2] << 16) + (read[1] << 8) + read[0];
            printf("%X", hold);
            global = 0;
            device.attach(eventQueue->event(callback), BufferedSerial::RxIrq);
        }

        //ThisThread::sleep_for(500);
        //printf("waiting\r\n");
    }
}

Best regards, Zoltan