pimoroni-pico/examples/plasma2040/plasma2040_monitor.cpp

#include <stdio.h>
#include <math.h>
#include <cstdint>

#include "pico/stdlib.h"

#include "plasma2040.hpp"

#include "common/pimoroni_common.hpp"
#include "bme68x.hpp"
#include "rgbled.hpp"
#include "button.hpp"

/*
Uses a BME68x to monitor the ambient temperature, pressure and humidity, and show them as bars on an LED strip.
Press "A" to cycle to the next mode.
Press "B" to cycle to the previous mode.
*/

using namespace pimoroni;
using namespace plasma;

// Set how many LEDs you have
const uint N_LEDS = 30;

// How many times the LEDs will be updated per second
const uint UPDATES = 60;

// The temperature range to show (in degrees celsius)
constexpr float TEMPERATURE_C_MIN = 20.0f;
constexpr float TEMPERATURE_C_MAX = 35.0f;

// The pressure range to show (in pascals)
constexpr float PRESSURE_PA_MIN = 87000.0f;
constexpr float PRESSURE_PA_MAX = 108500.0f;

// The humidity range to show (in percent)
constexpr float HUMIDITY_MIN = 0.0f;
constexpr float HUMIDITY_MAX = 100.0f;


// The start and end hues for the temperature range
constexpr float TEMPERATURE_HUE_START = 0.667f;
constexpr float TEMPERATURE_HUE_END = 1.0f;

// The start and end hues for the pressure range
constexpr float PRESSURE_HUE_START = 0.333f;
constexpr float PRESSURE_HUE_END = 0.0f;

// The start and end hues for the humidity range
constexpr float HUMIDITY_HUE_START = 0.333f;
constexpr float HUMIDITY_HUE_END = 0.667f;


// Pick *one* LED type by uncommenting the relevant line below:

// APA102-style LEDs with Data/Clock lines. AKA DotStar
//APA102 led_strip(N_LEDS, pio0, 0, plasma2040::DAT, plasma2040::CLK);

// WS28X-style LEDs with a single signal line. AKA NeoPixel
WS2812 led_strip(N_LEDS, pio0, 0, plasma2040::DAT);



Button button_a(plasma2040::BUTTON_A, ACTIVE_LOW, 0);
Button button_b(plasma2040::BUTTON_B, ACTIVE_LOW, 0);

RGBLED led(plasma2040::LED_R, plasma2040::LED_G, plasma2040::LED_B);

I2C i2c(BOARD::PICO_EXPLORER);
BME68X bme68x(&i2c);

enum DisplayMode {
  ALL,
  TEMPERATURE,
  PRESSURE,
  HUMIDITY
};

// Maps a value from one range to another
float map(float x, float in_min, float in_max, float out_min, float out_max) {
  return (x - in_min) * (out_max - out_min) / (in_max - in_min) + out_min;
}

// Sets a section of the led strip to show a hue gradient based on the provided percent
void colour_gauge(float percent, uint start_led, uint end_led, float start_hue, float end_hue) {
  if(end_led > start_led) {
    uint range = end_led - start_led;
    float light_pixels = percent * range;

    for(uint i = 0; i < range; i++) {
      float h = map(i, 0.0f, (float)range - 1, start_hue, end_hue);

      uint i2 = i + 1;
      if(i2 <= light_pixels) {
        led_strip.set_hsv(i + start_led, h, 1.0f, 1.0f);
      }
      else if(i <= light_pixels) {
        float scale = map(light_pixels, (float)i, (float)i2, 0.0f, 1.0f);
        led_strip.set_hsv(i + start_led, h, 1.0f, scale);
      }
      else {
        led_strip.set_hsv(i + start_led, 0.0f, 0.0f, 0.0f);
      }
    }
  }
}

int main() {
  stdio_init_all();

  led_strip.start(UPDATES);

  bool bme_detected = bme68x.init();


  uint first_third = led_strip.num_leds / 3;
  uint second_third = (led_strip.num_leds * 2) / 3;

  float t = 0.0f;
  DisplayMode mode = DisplayMode::ALL;
  while(true) {
    if(bme_detected) {
      bme68x_data data;

      auto result = bme68x.read_forced(&data);
      (void)result;

      printf("%.2fc, %.2fPa, %.2f%%\n", data.temperature, data.pressure, data.humidity);

      switch(mode) {
        case DisplayMode::ALL:
          t = map(data.temperature, TEMPERATURE_C_MIN, TEMPERATURE_C_MAX, 0.0f, 1.0f);
          colour_gauge(t, 0, first_third, TEMPERATURE_HUE_START, TEMPERATURE_HUE_END);

          t = map(data.pressure, PRESSURE_PA_MIN, PRESSURE_PA_MAX, 0.0f, 1.0f);
          colour_gauge(t, first_third, second_third, PRESSURE_HUE_START, PRESSURE_HUE_END);

          t = map(data.humidity, HUMIDITY_MIN, HUMIDITY_MAX, 0.0f, 1.0f);
          colour_gauge(t, second_third, led_strip.num_leds, HUMIDITY_HUE_START, HUMIDITY_HUE_END);
          break;

        case DisplayMode::TEMPERATURE:
          t = map(data.temperature, TEMPERATURE_C_MIN, TEMPERATURE_C_MAX, 0.0f, 1.0f);
          colour_gauge(t, 0, led_strip.num_leds, TEMPERATURE_HUE_START, TEMPERATURE_HUE_END);
          break;

        case DisplayMode::PRESSURE:
          t = map(data.pressure, PRESSURE_PA_MIN, PRESSURE_PA_MAX, 0.0f, 1.0f);
          colour_gauge(t, 0, led_strip.num_leds, PRESSURE_HUE_START, PRESSURE_HUE_END);
          break;

        case DisplayMode::HUMIDITY:
          t = map(data.humidity, HUMIDITY_MIN, HUMIDITY_MAX, 0.0f, 1.0f);
          colour_gauge(t, 0, led_strip.num_leds, HUMIDITY_HUE_START, HUMIDITY_HUE_END);
          break;
      }
    }
    bool a_pressed = button_a.read();
    bool b_pressed = button_b.read();

    switch(mode) {
      case DisplayMode::ALL:
        led.set_rgb(127, 127, 127);
        if(a_pressed) mode = DisplayMode::TEMPERATURE;
        else if(b_pressed) mode = DisplayMode::HUMIDITY;
        break;

      case DisplayMode::TEMPERATURE:
        led.set_rgb(255, 0, 255);
        if(a_pressed) mode = DisplayMode::PRESSURE;
        else if(b_pressed) mode = DisplayMode::ALL;
        break;

      case DisplayMode::PRESSURE:
        led.set_rgb(255, 255, 0);
        if(a_pressed) mode = DisplayMode::HUMIDITY;
        else if(b_pressed) mode = DisplayMode::TEMPERATURE;
        break;

      case DisplayMode::HUMIDITY:
        led.set_rgb(0, 255, 255);
        if(a_pressed) mode = DisplayMode::ALL;
        else if(b_pressed) mode = DisplayMode::PRESSURE;
        break;
    }
  }
}