Files
mongoose-touch/src/widget_battery.c
2017-11-27 23:14:17 +01:00

79 lines
2.1 KiB
C

#include "mgos.h"
#include "mgos_adc.h"
#include "mgos_config.h"
#include "tft.h"
#include "mongoose-touch.h"
#include "mgos_prometheus_metrics.h"
#define WIDGET_BATTERY_ADC_PIN 35
// Returns millivolts - Huzzah32 has a 1:1 voltage divider on I35 (A13)
// so it returns half of the battery voltage. Calibrate the function by
// measuring the ADC output at 4000mV.
static int widget_battery_getvoltage() {
int val, mvolts;
val = mgos_adc_read(WIDGET_BATTERY_ADC_PIN);
mvolts=(4000*val)/mgos_sys_config_get_app_battery_calibration();
LOG(LL_DEBUG, ("ADC value %d, voltage %d mV", val, mvolts));
return mvolts;
}
static void widget_battery_render(struct widget_t *w, void *ev_data) {
int mvolts;
color_t color;
uint8_t h;
if (!w)
return;
mgos_ili9341_setclipwin(w->x, w->y, w->x+w->w, w->y+w->h);
mvolts=widget_battery_getvoltage();
color=ILI9341_RED;
if (mvolts<3200) mvolts=3200;
if (mvolts>3500) color=ILI9341_YELLOW;
if (mvolts>3900) color=ILI9341_GREEN;
if (mvolts>4200) mvolts=4200;
h=12-12*(mvolts-3200)/(4200-3200);
mgos_ili9341_fillRect(5, 2, 3, 2, color);
mgos_ili9341_fillRect(2, 4, 9, 14, color);
mgos_ili9341_fillRect(3, 5, 7, h, ILI9341_BLACK);
mgos_ili9341_resetclipwin();
(void) ev_data;
}
static void prometheus_battery_metrics_fn(struct mg_connection *nc, void *user_data) {
mgos_prometheus_metrics_printf(nc, GAUGE,
"battery_mvolts", "Battery voltage in mV",
"%d", widget_battery_getvoltage());
(void) user_data;
}
void widget_battery_ev(int ev, struct widget_t *w, void *ev_data) {
if (!w)
return;
switch(ev) {
case EV_WIDGET_CREATE:
LOG(LL_INFO, ("Monitoring LiPo voltage on gpio=%d", WIDGET_BATTERY_ADC_PIN));
mgos_adc_enable(WIDGET_BATTERY_ADC_PIN);
mgos_prometheus_metrics_add_handler(prometheus_battery_metrics_fn, NULL);
case EV_WIDGET_DRAW:
case EV_WIDGET_REDRAW:
case EV_WIDGET_TIMER:
widget_battery_render(w, ev_data);
break;
case EV_WIDGET_TOUCH_UP:
case EV_WIDGET_TOUCH_DOWN:
case EV_WIDGET_DESTROY:
default: // EV_WIDGET_NONE
break;
}
}