unleashed-firmware/applications/plugins/temperature_sensor/temperature_sensor.c
2022-10-25 03:59:40 +03:00

299 lines
9.7 KiB
C

/* Flipper App to read the values from a HTU21D Sensor */
/* Created by Mywk - https://github.com/Mywk - https://mywk.net */
#include <furi.h>
#include <furi_hal.h>
#include <furi_hal_i2c.h>
#include <math.h>
#include <gui/gui.h>
#include <input/input.h>
#include <notification/notification_messages.h>
#include <string.h>
#define TS_DEFAULT_VALUE 0xFFFF
#define HTU21D_ADDRESS (0x40 << 1)
#define HTU21D_CMD_TEMPERATURE 0xE3
#define HTU21D_CMD_HUMIDITY 0xE5
#define DATA_BUFFER_SIZE 8
// External I2C BUS
#define I2C_BUS &furi_hal_i2c_handle_external
typedef enum {
TSSInitializing,
TSSNoSensor,
TSSPendingUpdate,
} TSStatus;
typedef enum {
TSEventTypeTick,
TSEventTypeInput,
} TSEventType;
typedef struct {
TSEventType type;
InputEvent input;
} TSEvent;
extern const NotificationSequence sequence_blink_red_100;
extern const NotificationSequence sequence_blink_blue_100;
static TSStatus temperature_sensor_current_status = TSSInitializing;
// Temperature and Humidity data buffers, ready to print
char ts_data_buffer_temperature_c[DATA_BUFFER_SIZE];
char ts_data_buffer_temperature_f[DATA_BUFFER_SIZE];
char ts_data_buffer_relative_humidity[DATA_BUFFER_SIZE];
char ts_data_buffer_absolute_humidity[DATA_BUFFER_SIZE];
// <sumary>
// Executes an I2C cmd (trx)
// </sumary>
// <returns>
// true if fetch was successful, false otherwise
// </returns>
static bool temperature_sensor_cmd(uint8_t cmd, uint8_t* buffer, uint8_t size) {
uint32_t timeout = furi_ms_to_ticks(100);
bool ret = false;
// Aquire I2C and check if device is ready, then release
furi_hal_i2c_acquire(I2C_BUS);
if(furi_hal_i2c_is_device_ready(I2C_BUS, HTU21D_ADDRESS, timeout)) {
furi_hal_i2c_release(I2C_BUS);
furi_hal_i2c_acquire(I2C_BUS);
// Transmit given command
ret = furi_hal_i2c_tx(I2C_BUS, HTU21D_ADDRESS, &cmd, 1, timeout);
furi_hal_i2c_release(I2C_BUS);
if(ret) {
uint32_t wait_ticks = furi_ms_to_ticks(50);
furi_delay_tick(wait_ticks);
furi_hal_i2c_acquire(I2C_BUS);
// Receive data
ret = furi_hal_i2c_rx(I2C_BUS, HTU21D_ADDRESS, buffer, size, timeout);
furi_hal_i2c_release(I2C_BUS);
}
} else {
furi_hal_i2c_release(I2C_BUS);
}
return ret;
}
// <sumary>
// Fetches temperature and humidity from sensor
// </sumary>
// <remarks>
// Temperature and humidity must be preallocated
// Note: CRC is not checked (3rd byte)
// </remarks>
// <returns>
// true if fetch was successful, false otherwise
// </returns>
static bool temperature_sensor_fetch_data(double* temperature, double* humidity) {
bool ret = false;
uint16_t adc_raw;
uint8_t buffer[2] = {0x00};
// Fetch temperature
ret = temperature_sensor_cmd((uint8_t)HTU21D_CMD_TEMPERATURE, buffer, 2);
if(ret) {
// Calculate temperature
adc_raw = ((uint16_t)(buffer[0] << 8) | (buffer[1]));
*temperature = (float)(adc_raw * 175.72 / 65536.00) - 46.85;
// Fetch humidity
ret = temperature_sensor_cmd((uint8_t)HTU21D_CMD_TEMPERATURE, buffer, 2);
if(ret) {
// Calculate humidity
adc_raw = ((uint16_t)(buffer[0] << 8) | (buffer[1]));
*humidity = (float)(adc_raw * 125.0 / 65536.00) - 6.0;
}
}
return ret;
}
// <sumary>
// Draw callback
// </sumary>
static void temperature_sensor_draw_callback(Canvas* canvas, void* ctx) {
UNUSED(ctx);
canvas_clear(canvas);
canvas_set_font(canvas, FontPrimary);
canvas_draw_str(canvas, 2, 10, "HTU21D/Si7021 Sensor");
canvas_set_font(canvas, FontSecondary);
canvas_draw_str(canvas, 2, 62, "Press back to exit.");
switch(temperature_sensor_current_status) {
case TSSInitializing:
canvas_draw_str(canvas, 2, 30, "Initializing..");
break;
case TSSNoSensor:
canvas_draw_str(canvas, 2, 30, "No sensor found!");
break;
case TSSPendingUpdate: {
canvas_draw_str(canvas, 3, 24, "Temperature");
canvas_draw_str(canvas, 68, 24, "Humidity");
// Draw vertical lines
canvas_draw_line(canvas, 61, 16, 61, 50);
canvas_draw_line(canvas, 62, 16, 62, 50);
// Draw horizontal line
canvas_draw_line(canvas, 2, 27, 122, 27);
// Draw temperature and humidity values
canvas_draw_str(canvas, 8, 38, ts_data_buffer_temperature_c);
canvas_draw_str(canvas, 42, 38, "C");
canvas_draw_str(canvas, 8, 48, ts_data_buffer_temperature_f);
canvas_draw_str(canvas, 42, 48, "F");
canvas_draw_str(canvas, 68, 38, ts_data_buffer_relative_humidity);
canvas_draw_str(canvas, 100, 38, "%");
canvas_draw_str(canvas, 68, 48, ts_data_buffer_absolute_humidity);
canvas_draw_str(canvas, 100, 48, "g/m3");
} break;
default:
break;
}
}
// <sumary>
// Input callback
// </sumary>
static void temperature_sensor_input_callback(InputEvent* input_event, void* ctx) {
furi_assert(ctx);
FuriMessageQueue* event_queue = ctx;
TSEvent event = {.type = TSEventTypeInput, .input = *input_event};
furi_message_queue_put(event_queue, &event, FuriWaitForever);
}
// <sumary>
// Timer callback
// </sumary>
static void temperature_sensor_timer_callback(FuriMessageQueue* event_queue) {
furi_assert(event_queue);
TSEvent event = {.type = TSEventTypeTick};
furi_message_queue_put(event_queue, &event, 0);
}
// <sumary>
// App entry point
// </sumary>
int32_t temperature_sensor_app(void* p) {
UNUSED(p);
furi_hal_power_suppress_charge_enter();
// Declare our variables and assign variables a default value
TSEvent tsEvent;
bool sensorFound = false;
double celsius, fahrenheit, rel_humidity, abs_humidity = TS_DEFAULT_VALUE;
// Used for absolute humidity calculation
double vapour_pressure = 0;
FuriMessageQueue* event_queue = furi_message_queue_alloc(8, sizeof(TSEvent));
// Register callbacks
ViewPort* view_port = view_port_alloc();
view_port_draw_callback_set(view_port, temperature_sensor_draw_callback, NULL);
view_port_input_callback_set(view_port, temperature_sensor_input_callback, event_queue);
// Create timer and register its callback
FuriTimer* timer =
furi_timer_alloc(temperature_sensor_timer_callback, FuriTimerTypePeriodic, event_queue);
furi_timer_start(timer, furi_kernel_get_tick_frequency());
// Register viewport
Gui* gui = furi_record_open(RECORD_GUI);
gui_add_view_port(gui, view_port, GuiLayerFullscreen);
// Used to notify the user by blinking red (error) or blue (fetch successful)
NotificationApp* notifications = furi_record_open(RECORD_NOTIFICATION);
while(1) {
furi_check(furi_message_queue_get(event_queue, &tsEvent, FuriWaitForever) == FuriStatusOk);
// Handle events
if(tsEvent.type == TSEventTypeInput) {
// Exit on back key
if(tsEvent.input.key ==
InputKeyBack) // We dont check for type here, we can check the type of keypress like: (event.input.type == InputTypeShort)
break;
} else if(tsEvent.type == TSEventTypeTick) {
// Update sensor data
// Fetch data and set the sensor current status accordingly
sensorFound = temperature_sensor_fetch_data(&celsius, &rel_humidity);
temperature_sensor_current_status = (sensorFound ? TSSPendingUpdate : TSSNoSensor);
if(sensorFound) {
// Blink blue
notification_message(notifications, &sequence_blink_blue_100);
if(celsius != TS_DEFAULT_VALUE && rel_humidity != TS_DEFAULT_VALUE) {
// Convert celsius to fahrenheit
fahrenheit = (celsius * 9 / 5) + 32;
// Calculate absolute humidity - For more info refer to https://github.com/Mywk/FlipperTemperatureSensor/issues/1
// Calculate saturation vapour pressure first
vapour_pressure =
(double)6.11 *
pow(10, (double)(((double)7.5 * celsius) / ((double)237.3 + celsius)));
// Then the vapour pressure in Pa
vapour_pressure = vapour_pressure * rel_humidity;
// Calculate absolute humidity
abs_humidity =
(double)2.16679 * (double)(vapour_pressure / ((double)273.15 + celsius));
// Fill our buffers here, not on the canvas draw callback
snprintf(ts_data_buffer_temperature_c, DATA_BUFFER_SIZE, "%.2f", celsius);
snprintf(ts_data_buffer_temperature_f, DATA_BUFFER_SIZE, "%.2f", fahrenheit);
snprintf(
ts_data_buffer_relative_humidity, DATA_BUFFER_SIZE, "%.2f", rel_humidity);
snprintf(
ts_data_buffer_absolute_humidity, DATA_BUFFER_SIZE, "%.2f", abs_humidity);
}
} else {
// Reset our variables to their default values
celsius = fahrenheit = rel_humidity = abs_humidity = TS_DEFAULT_VALUE;
// Blink red
notification_message(notifications, &sequence_blink_red_100);
}
}
uint32_t wait_ticks = furi_ms_to_ticks(!sensorFound ? 100 : 500);
furi_delay_tick(wait_ticks);
}
furi_hal_power_suppress_charge_exit();
// Dobby is freee (free our variables, Flipper will crash if we don't do this!)
furi_timer_free(timer);
gui_remove_view_port(gui, view_port);
view_port_free(view_port);
furi_message_queue_free(event_queue);
furi_record_close(RECORD_NOTIFICATION);
furi_record_close(RECORD_GUI);
return 0;
}