add

firmware/diag_s3/platformio.ini

@@ -0,0 +1,10 @@
+[env:esp32-s3]
+platform = espressif32
+board = esp32-s3-devkitc-1
+framework = arduino
+monitor_speed = 115200
+upload_speed = 921600
+build_flags =
+    -D ARDUINO_USB_CDC_ON_BOOT=0
+lib_deps =
+    adafruit/Adafruit MPU6050@^2.2.4

firmware/diag_s3/src/main.cpp

@@ -0,0 +1,61 @@
+#include <Arduino.h>
+#include <Wire.h>
+#include <Adafruit_MPU6050.h>
+#include <Adafruit_Sensor.h>
+
+static constexpr uint8_t SDA_PIN = 4;
+static constexpr uint8_t SCL_PIN = 5;
+Adafruit_MPU6050 mpu;
+
+void scanI2C() {
+    Serial.println("[I2C] scan start");
+    uint8_t found = 0;
+
+    for (uint8_t addr = 1; addr < 127; addr++) {
+        Wire.beginTransmission(addr);
+        uint8_t err = Wire.endTransmission();
+        if (err == 0) {
+            Serial.printf("[I2C] found device at 0x%02X\n", addr);
+            found++;
+        }
+    }
+
+    if (!found) {
+        Serial.println("[I2C] no devices found");
+    }
+    Serial.println("[I2C] scan done");
+}
+
+void setup() {
+    Serial.begin(115200);
+    delay(500);
+    Serial.println();
+    Serial.println("ESP32-S3 I2C diagnostic");
+    Serial.printf("Pins: SDA=%u SCL=%u\n", SDA_PIN, SCL_PIN);
+    Wire.begin(SDA_PIN, SCL_PIN, 100000);
+    delay(100);
+    scanI2C();
+
+    if (!mpu.begin(0x68, &Wire)) {
+        Serial.println("[MPU] begin failed");
+        return;
+    }
+
+    mpu.setAccelerometerRange(MPU6050_RANGE_2_G);
+    mpu.setGyroRange(MPU6050_RANGE_250_DEG);
+    mpu.setFilterBandwidth(MPU6050_BAND_21_HZ);
+    Serial.println("[MPU] begin ok");
+
+    sensors_event_t accel, gyro, temp;
+    mpu.getEvent(&accel, &gyro, &temp);
+    Serial.printf("[MPU] accel=(%.2f, %.2f, %.2f) temp=%.2f\n",
+                 accel.acceleration.x, accel.acceleration.y, accel.acceleration.z, temp.temperature);
+}
+
+void loop() {
+    static uint32_t last = 0;
+    if (millis() - last > 3000) {
+        last = millis();
+        scanI2C();
+    }
+}