【2024 DigiKey Creative Competition】ESP-32-S3- Entry-level radar detection + voice broadcast

御坂10032号

【2024 DigiKey Creative Competition】ESP-32-S3- Entry-level radar detection + voice broadcast [Copy link]

 

Introduction

This chapter mainly completes the function of living room entry detection. Specifically, the radar module is used to detect whether there is human movement. If there is human movement, the radar will send a high level to the ESP32S3-devkit, and then this high level signal will be captured by the interrupt, thereby lighting up the red LED and driving the MX98357 module to play audio.

The wiring diagram is as follows:

I would like to thank the group members for providing I2S configuration guidance.

After the help of group friends, I successfully customized and initialized the specific PIN of I2S and played a simple tone. The specific demo is from the figure below.

If your board is wired correctly, you can hear a "beep~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~" sound.

Now we need to solve a problem, which is how to read the WAV format. There are many ways to play it, such as accessing the audio files saved in the SD card through the network or through the SD card. But since I am detecting the return of the living room personnel, I only need to play a "Welcome Home". So I used the AI voice generation website to generate a "Welcome Home" voice.

I encountered many problems when converting WAV audio. I will not post the unsolved bugs here. I found a good solution. Please refer to this post

The specific steps are: first use Audacity to convert the data into unsigned 8-bit WAV format. Then use Freeware Hex Editor and Disk Editor to open the WAV format data, select all the data and copy it into a C language array.

As shown in the figure below

Modify the original code for playing the tone as shown below (delete the code for playing audio data)

#include <ESP_I2S.h>
#include <Adafruit_NeoPixel.h>

#define LED_PIN 38       // Pin connected to the data input of SK68XXMINI-HS
#define NUMPIXELS 1      // Number of LEDs (set to 1 if using a single SK68XXMINI-HS)
#define INTERRUPT_PIN 1  // Pin connected to IO1 for detecting high/low signal

Adafruit_NeoPixel pixels(NUMPIXELS, LED_PIN, NEO_GRB + NEO_KHZ800);

bool ledOn = false;  // LED state

void IRAM_ATTR handleInterrupt() {
  // Toggle LED state based on the level of INTERRUPT_PIN
  ledOn = digitalRead(INTERRUPT_PIN);  // Read the state of the pin (HIGH or LOW)
}

unsigned char rawData[66044] = {
  
};


const size_t wavDataSize = sizeof(rawData) / sizeof(rawData[0]);

i2s_data_bit_width_t bps = I2S_DATA_BIT_WIDTH_16BIT;
i2s_mode_t mode = I2S_MODE_STD;
i2s_slot_mode_t slot = I2S_SLOT_MODE_MONO;

I2SClass i2s;

void setup() {
  Serial.begin(115200);
  Serial.println("I2S playback from array");

  pinMode(INTERRUPT_PIN, INPUT);                                                   // Set INTERRUPT_PIN (IO1) as input
  attachInterrupt(digitalPinToInterrupt(INTERRUPT_PIN), handleInterrupt, CHANGE);  // Trigger on any change in level (HIGH or LOW)

  i2s.setPins(41, 42, 40);  // BCLK, LRC, DIN
  // 启动 I2S，设置采样率和每个样本的位宽
  if (!i2s.begin(mode, 30000, bps, slot)) {  // 假设采样率为 48000 Hz
    Serial.println("Failed to initialize I2S!");
    while (1)
      ;  // 不执行任何操作
  }
  pixels.begin();  // 初始化 LED
}

void loop() {
  if (ledOn) {
    // 点亮红色 LED
    pixels.setPixelColor(0, pixels.Color(255, 0, 0));  // 设置为红色
    pixels.show();                                     // 更新 LED 显示

    // 播放 WAV 数据
    for (size_t i = 0; i < wavDataSize; i++) {
      i2s.write(rawData[i]);  // 写入样本到 I2S
    }
  } else {
    // 关闭 LED
    pixels.setPixelColor(0, pixels.Color(0, 0, 0));  // 关闭 LED
    pixels.show();                                   // 更新 LED 显示
  }

  delay(5000);  // 添加一个小延迟，避免过于频繁的读取
}

And put the copied audio array in rawData. At the same time, bind the IO interrupt to read the radar feedback. It should be noted that you may need to adjust the sampling rate manually. When I downloaded this audio file, I checked that the sampling rate should be 48KHZ, but if it is played at 48KHZ, the audio will lose frames. So I adjusted the sampling rate and the delay after playing each array element for a long time. Finally, I got the code above.

The complete code for playing audio is as follows:

music_play.ino (399.74 KB, downloads: 0)

2024-10-29 01:02 上传

点击文件名下载附件

AI generated voice files:

1.wav (128.95 KB, downloads: 0)

2024-10-29 01:04 上传

点击文件名下载附件

Video Demonstration

3993b1d95758a1fe66c5d0ecd9c505e2

wangerxian

I will also use voice broadcast later, can 16KHz audio be played?

秦天qintian0303

In a confined space, can the radar also detect the

xftbdv42631

The information you shared is very good and helpful to me. Thank you for sharing such good information!

御坂10032号

wangerxian posted on 2024-10-29 09:01 I will also use voice broadcasting later. Can 16KHz audio be played?

I haven't tried it, if your audio is ok then it should be fine.

御坂10032号

Qintianqintian0303 posted on 2024-10-29 09:08 In a confined space, can the radar also detect the reverse direction?

No, this radar is just a very ordinary radar. Better radars will not have this problem.