STM32F103C8T6 + HC-SR04 + 0.96 OLED 测距资料

#define TRIG_PIN PA0
#define ECHO_PIN PA1

HardwareSerial DebugSerial(PA10, PA9); // RX, TX
Adafruit_SSD1306 display(128, 64, &Wire, -1);

// OLED I2C: SCL=PB6, SDA=PB7
display.begin(SSD1306_SWITCHCAPVCC, 0x3C);

[env:bluepill_f103c8]
platform = ststm32
board = bluepill_f103c8
framework = arduino
upload_protocol = stlink
monitor_speed = 115200
lib_deps =
    adafruit/Adafruit SSD1306@^2.5.13
    adafruit/Adafruit GFX Library@^1.11.11

main.cpp 核心示例

// HC-SR04 + STM32F103C8T6 + 0.96 OLED
// Trig=PA0, Echo=PA1
// OLED: SCL=PB6, SDA=PB7, address=0x3C
// Serial monitor: CP2102 TX->PA10, RX->PA9, 115200

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

#define TRIG_PIN PA0
#define ECHO_PIN PA1
#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 64

HardwareSerial DebugSerial(PA10, PA9); // RX, TX
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, -1);

float getDistanceCM() {
  digitalWrite(TRIG_PIN, LOW);
  delayMicroseconds(2);
  digitalWrite(TRIG_PIN, HIGH);
  delayMicroseconds(10);
  digitalWrite(TRIG_PIN, LOW);

  unsigned long duration = pulseIn(ECHO_PIN, HIGH, 30000);
  if (duration == 0) return -1;
  return duration * 0.0343f / 2.0f;
}

void showDistance(float cm) {
  display.clearDisplay();
  display.setTextColor(SSD1306_WHITE);
  display.setTextSize(1);
  display.setCursor(0, 0);
  display.println("HC-SR04 Distance");

  display.setTextSize(2);
  display.setCursor(0, 24);
  if (cm < 0) {
    display.println("No echo");
  } else {
    display.print(cm, 1);
    display.println(" cm");
  }
  display.display();
}

void setup() {
  DebugSerial.begin(115200);
  pinMode(TRIG_PIN, OUTPUT);
  pinMode(ECHO_PIN, INPUT);
  digitalWrite(TRIG_PIN, LOW);

  Wire.begin();
  if (!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) {
    DebugSerial.println("OLED init failed");
    while (1) delay(100);
  }
  display.clearDisplay();
  display.display();
}

void loop() {
  float cm = getDistanceCM();
  showDistance(cm);

  DebugSerial.print("Distance: ");
  if (cm < 0) DebugSerial.println("No echo");
  else {
    DebugSerial.print(cm, 1);
    DebugSerial.println(" cm");
  }
  delay(200);
}