Battery API Example

An example running on Myriota's FlexSense board. This example demonstrates how to use the Battery API's. The BatterySample job will sample if the device is externally or battery-powered FLEX_IsOnExternalPower and the battery voltage FLEX_GetBatteryVoltage. BatterySample will be scheduled SAMPLES_PER_DAY times per day.

 
#include <stdio.h>
#include "flex.h"
 
#define APPLICATION_NAME "Battery API Example"
 
// Sample frequency
#define SAMPLES_PER_DAY 4
 
// Sample if the FlexSense device is externally powered and the battery voltage.
static time_t BatterySample(void) {
  // Check if the FlexSense is externally powered (via USB or the FlexSense external cable
  // interface)
  bool is_on_external_power = false;
  if (FLEX_IsOnExternalPower(&is_on_external_power) != 0) {
    printf("Failed to read is on external power!\n");
  }
 
  // Get the battery voltage. The voltage will be 0 if externally powered.
  int32_t battery_mv = 0;
  if (FLEX_GetBatteryVoltage(&battery_mv) != 0) {
    printf("Failed to read battery voltage!\n");
  }
 
  // Print the results on the debug console.
  printf("Battery API Sample: Is on external power = %d, Battery mV = %ld\n", is_on_external_power,
    battery_mv);
 
  return (FLEX_TimeGet() + 24 * 3600 / SAMPLES_PER_DAY);
}
 
static void on_external_power_handler(const bool *const is_ext_pwr) {
  char buf[32] = {0};
  snprintf(buf, sizeof(buf), "External Power: (%d)\n", *is_ext_pwr);
}
 
void FLEX_AppInit() {
  printf("%s\n", APPLICATION_NAME);
  FLEX_JobSchedule(BatterySample, FLEX_ASAP());
 
  // Sample the `is external power` status and the battery voltage if the external power status
  // changes. If the external power status does not change then the sample will be every
  // DAYS_BETWEEN_MESSAGES days
  FLEX_OnExternalPowerHandlerSet(on_external_power_handler);
}