BH1750 光照传感器 STM32F103 接线与代码

/*
 * ==================== FIRMWARE VERSION ====================
 * Project: 01_BH1750
 * Board: STM32F103C8T6 / BluePill
 * Current firmware: BH1750 UI 1.1
 * Version tag on OLED/Serial: BH1750 UI 1.1
 * Base stable firmware: main_v4_实测通过_20260814.cpp
 * Date: 2026-08-14
 *
 * UI 1.1 changes:
 * - Larger lux value for video recording
 * - Simple animated sun icon
 * - Lux bar
 * - DARK / NORMAL / BRIGHT status
 *
 * Save rule:
 * After this version is confirmed by real hardware test, copy this file to:
 * 固件/稳定版本/main_ui_v1_1_大字体图标动画_实测通过_20260814.cpp
 * ==========================================================
 */

#include <Arduino.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>
#include <Wire.h>

constexpr uint8_t OLED_ADDR = 0x3C;
constexpr uint8_t BH1750_ADDR = 0x23;
constexpr int SCREEN_WIDTH = 128;
constexpr int SCREEN_HEIGHT = 64;
constexpr char FW_VERSION[] = "BH1750 UI 1.1";
constexpr uint8_t BAR_X = 6;
constexpr uint8_t BAR_Y = 54;
constexpr uint8_t BAR_W = 78;
constexpr uint8_t BAR_H = 7;

Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, -1);
bool sunFrame = false;

bool bh1750Write(uint8_t command) {
  Wire.beginTransmission(BH1750_ADDR);
  Wire.write(command);
  return Wire.endTransmission() == 0;
}

bool i2cDeviceFound(uint8_t address) {
  Wire.beginTransmission(address);
  return Wire.endTransmission() == 0;
}

bool bh1750Init() {
  if (!bh1750Write(0x01)) {
    return false;
  }
  delay(10);

  if (!bh1750Write(0x07)) {
    return false;
  }
  delay(10);

  if (!bh1750Write(0x10)) {
    return false;
  }

  delay(180);
  return true;
}

bool bh1750ReadLux(float &lux) {
  Wire.requestFrom(BH1750_ADDR, static_cast<uint8_t>(2));
  if (Wire.available() < 2) {
    bh1750Write(0x10);
    delay(180);
    return false;
  }

  uint16_t raw = static_cast<uint16_t>(Wire.read()) << 8;
  raw |= Wire.read();
  lux = raw / 1.2f;
  return true;
}

void showStatus(const char *line1, const char *line2) {
  display.clearDisplay();
  display.setTextColor(SSD1306_WHITE);
  display.setTextSize(1);
  display.setCursor(0, 0);
  display.println(FW_VERSION);
  display.println();
  display.println(line1);
  display.println(line2);
  display.display();
}

const char *luxStatus(float lux) {
  if (lux < 20.0f) {
    return "DARK";
  }
  if (lux > 200.0f) {
    return "BRIGHT";
  }
  return "NORMAL";
}

void drawSunIcon(int16_t x, int16_t y, bool frame) {
  display.drawCircle(x, y, 3, SSD1306_WHITE);
  if (frame) {
    display.drawPixel(x, y - 7, SSD1306_WHITE);
    display.drawPixel(x, y + 7, SSD1306_WHITE);
    display.drawPixel(x - 7, y, SSD1306_WHITE);
    display.drawPixel(x + 7, y, SSD1306_WHITE);
  } else {
    display.drawLine(x - 5, y - 5, x - 7, y - 7, SSD1306_WHITE);
    display.drawLine(x + 5, y - 5, x + 7, y - 7, SSD1306_WHITE);
    display.drawLine(x - 5, y + 5, x - 7, y + 7, SSD1306_WHITE);
    display.drawLine(x + 5, y + 5, x + 7, y + 7, SSD1306_WHITE);
  }
}

void drawLuxBar(float lux) {
  float clamped = lux;
  if (clamped < 0.0f) {
    clamped = 0.0f;
  }
  if (clamped > 1000.0f) {
    clamped = 1000.0f;
  }

  uint8_t fillW = static_cast<uint8_t>((clamped / 1000.0f) * (BAR_W - 2));
  display.drawRect(BAR_X, BAR_Y, BAR_W, BAR_H, SSD1306_WHITE);
  display.fillRect(BAR_X + 1, BAR_Y + 1, fillW, BAR_H - 2, SSD1306_WHITE);
}

void showLux(float lux) {
  const char *status = luxStatus(lux);

  display.clearDisplay();
  display.setTextColor(SSD1306_WHITE);

  display.setTextSize(1);
  drawSunIcon(10, 8, sunFrame);
  display.setCursor(22, 2);
  display.println("BH1750");

  display.setTextSize(2);
  display.setCursor(18, 20);
  display.println(lux, 1);
  display.setTextSize(1);
  display.setCursor(88, 28);
  display.println("lux");

  drawLuxBar(lux);
  display.setCursor(90, 53);
  display.println(status);

  display.display();
  sunFrame = !sunFrame;
}

void showBootScreen() {
  display.clearDisplay();
  display.setTextColor(SSD1306_WHITE);
  display.setTextSize(1);
  display.setCursor(0, 0);
  display.println(FW_VERSION);
  display.println();
  display.println("OLED UI 1.1");
  display.println("PB8 SCL PB9 SDA");
  display.println("Booting...");
  display.display();
}

void setup() {
  Serial.begin(115200);
  delay(300);

  Wire.setSCL(PB8);
  Wire.setSDA(PB9);
  Wire.begin();
  Wire.setClock(100000);

  if (!display.begin(SSD1306_SWITCHCAPVCC, OLED_ADDR)) {
    Serial.println("OLED init failed");
    while (true) {
      delay(1000);
    }
  }

  showBootScreen();
  Serial.println();
  Serial.println(FW_VERSION);
  Serial.println("OLED UI 1.1");
  delay(1200);

  showStatus("OLED OK", "BH1750 init...");

  Serial.print("OLED 0x3C: ");
  Serial.println(i2cDeviceFound(OLED_ADDR) ? "found" : "not found");
  Serial.print("BH1750 0x23: ");
  Serial.println(i2cDeviceFound(BH1750_ADDR) ? "found" : "not found");

  if (!bh1750Init()) {
    showStatus("BH1750 failed", "Check wiring");
    Serial.println("BH1750 init failed");
  } else {
    showStatus("BH1750 ready", "PB8/PB9 I2C");
    Serial.println("BH1750 ready");
  }
}

void loop() {
  float lux = 0.0f;

  if (bh1750ReadLux(lux)) {
    showLux(lux);
    Serial.print("Lux:");
    Serial.println(lux, 1);
  } else {
    showStatus("Read failed", "Check PB8/PB9");
    Serial.println("BH1750 read failed");
  }

  delay(1000);
}