main.cpp

#include "mbed.h"

/* Mail */
typedef struct {
    float    voltage; /* AD result of measured voltage */
    float    current; /* AD result of measured current */
    uint32_t counter; /* A counter value               */
} mail_t;

Mail<mail_t, 16> mail_box;
Thread thread;

void send_thread(void)
{
    uint32_t i = 0;
    while (true) {
        i++; // fake data update
        mail_t *mail = mail_box.alloc();
        mail->voltage = (i * 0.1) * 33;
        mail->current = (i * 0.1) * 11;
        mail->counter = i;
        mail_box.put(mail);
        ThisThread::sleep_for(1000);
    }
}

int main(void)
{
    thread.start(callback(send_thread));

    while (true) {
        // Non Blocking we coculd use try_get_for() to block
        // Will also become blocking in a future release
        osEvent evt = mail_box.get();
        if (evt.status == osEventMail) {
            mail_t *mail = (mail_t *)evt.value.p;
            printf("\nVoltage: %0.2f V\n\r", mail->voltage);
            printf("Current: %0.2f A\n\r", mail->current);
            printf("Number of cycles: %lu\n\r", mail->counter);

            mail_box.free(mail);
        }
    }
}