Trying to get simple record script going, no examples or discussions helping: Audio kit Mic > SD (as .wav)

[dandeliondandy]

Hi,
I'm only a week or so into microprocessors and Audio tools, and I'm working my way through the wiki and examples, but I've stayed up too late, too many nights struggling with getting a simple .WAV file to record to my SD card.

All the example .ino files in the library lead the to same final result, which is a short, garbled audio clip, as if whatever amount of data the file had was always being compressed into the same file size/length.

I'm starting to feel like I'm going crazy, and I would love to just be told that I'm doing one or two stupid things, or where to read in the Wiki exactly. This is a crucial small sketch to a larger project I'd love to make, and it's incredibly frustrating to spend hours and hours and always end up with the same failed result.

ESP32 A1S audio kit. everything built in.

#include "AudioTools.h"
#include "AudioTools/AudioLibs/AudioBoardStream.h"
#include "SD.h"

// --- Config ---
AudioInfo info(44100, 1, 16); 
const char* fileName = "/final_mono_track.wav";

// --- Global Objects ---
AudioBoardStream kit(AudioKitEs8388V1);
File audioFile;
WAVEncoder wavEncoder;
EncodedAudioStream *outStream = nullptr;
StreamCopy *copier = nullptr;
bool isRecording = false;

// ======================================================================================
// BUTTON HANDLER
// ======================================================================================
void handleRecordButton(bool active, int pin, void* ptr) {
  if (active) { 
    if (!isRecording) {
      // --- START RECORDING ---
      Serial.println("Starting recording...");
      audioFile = SD.open(fileName, FILE_WRITE);
      if (audioFile) {
        outStream = new EncodedAudioStream(&audioFile, &wavEncoder);
        outStream->begin(info);
        copier = new StreamCopy(*outStream, kit);
        isRecording = true;
        Serial.println("--> RECORDING MONO");
      } else {
        Serial.println("Failed to open file!");
      }

    } else {
      // --- STOP RECORDING ---
      Serial.println("Stopping recording...");
      isRecording = false; 
      
      if (copier != nullptr) {
        copier->copy();
        delete copier;
        copier = nullptr;
      }
      if (outStream != nullptr) {
        outStream->end();
        delete outStream;
        outStream = nullptr;
      }
      if (audioFile) {
        audioFile.close();
      }
      Serial.println("File saved.");
    }
  }
}

// ======================================================================================
// SETUP
// ======================================================================================
void setup() {
  Serial.begin(115200);
  AudioLogger::instance().begin(Serial, AudioLogger::Warning);
  Serial.println("\n--- Final Mono WAV Recorder ---");

  // --- 1. Configure and start the Audio Kit ---
  auto cfg = kit.defaultConfig(RXTX_MODE);
  cfg.input_device = ADC_INPUT_LINE2; 
  cfg.copyFrom(info);


  cfg.channels = 1;

  cfg.sd_active = true; 
  kit.begin(cfg);

  // --- 2. Initialize the SD Card File System ---
  if (!SD.begin(PIN_AUDIO_KIT_SD_CARD_CS)) {
    Serial.println("FATAL: SD Card failed to mount!");
    while(1);
  }
  Serial.println("SD Card Initialized.");
  
  // --- 3. Set up the single, non-conflicting REC button ---
  kit.audioActions().setDebounceDelay(20);
  kit.audioActions().add(kit.getKey(1), handleRecordButton);
  
  Serial.println("Ready. Press REC button to start/stop recording.");
}

// ======================================================================================
// LOOP
// ======================================================================================
void loop() {
  // Always process button actions
  kit.processActions(); 

  // If we are recording, run the copier to move one chunk of data
  if (isRecording && copier != nullptr) {
    copier->copy();
  }
}

[pschatzmann]

There are quite a few things that can go wrong:

• What is the output if you set the log level to info ? You should see repeated copy lines while recording.
• The SD library is quite slow and might not keep up with the amout of data produced : did you try to reduce the sample rate ? I would recommend to use SDMMC instead of the SD
• For testing: Try to add an audioFile.flush(); after each copy step to force a write to the SD card
• I would recommend to print the file size at the end to get a visual confirmation of the stored data
• Maybe something is wrong with your SD card: here is a similar tested sketch that records and plays.

ps.

• As a general note: On Microcontrollers it is not recommended to use new and delete because of the risk of memory fragmentation

[dandeliondandy]

Thanks so much for your reply. The linked test sketch has the same issue as my various attempts. However, after about five attempts, the audio does seem more or less record correctly. I've tested with both an older, slower SD card, and a new and fast SD card.

I was unable to try SDMMC, it always claimed the SD card could not be mounted. I suppose because of the PIN SDMMC expects? (I have had "successful" recordings with the normal SD.h, other than the above issues).

I'm sorry if I'm missing something super obvious. I thought that recording a file to the SD card would be a good first project after a basic looper/overdub sketch. hah

From your example, now attempting a test with info log level, this is what I get (and no audio this time):

09:45:50.236 -> ets Jul 29 2019 12:21:46
09:45:50.236 -> 
09:45:50.236 -> rst:0x1 (POWERON_RESET),boot:0x1f (SPI_FAST_FLASH_BOOT)
09:45:50.236 -> configsip: 0, SPIWP:0xee
09:45:50.236 -> clk_drv:0x00,q_drv:0x00,d_drv:0x00,cs0_drv:0x00,hd_drv:0x00,wp_drv:0x00
09:45:50.236 -> mode:DIO, clock div:1
09:45:50.281 -> load:0x3fff0030,len:4980
09:45:50.281 -> load:0x40078000,len:16612
09:45:50.281 -> load:0x40080400,len:3480
09:45:50.281 -> entry 0x400805b4
09:45:50.899 -> [    29][I][esp32-hal-psram.c:104] psramAddToHeap(): PSRAM added to the heap.
09:45:50.932 -> E (22) gpio: gpio_pullup_en(78): GPIO number error (input-only pad has no internal PU)
09:45:50.932 -> Warning: Pin '13' not set up because of conflict
09:45:50.969 -> E (32) gpio: gpio_pullup_en(78): GPIO number error (input-only pad has no internal PU)
09:45:50.969 -> [    62][I][esp32-hal-i2c-ng.c:112] i2cInit(): Initializing I2C Master: num=0 sda=33 scl=32 freq=100000
09:45:50.969 -> [W] I2SESP32V1.h : 239 - Using channel_format: I2SChannelSelect::Left for mono
09:45:51.052 -> Initialization done.
09:45:51.052 -> Press Key 1 to record
09:46:14.125 -> Recording...
09:46:14.125 -> [ 23234][W][sd_diskio.cpp:181] sdCommand(): crc error
09:46:14.264 -> [ 23353][W][sd_diskio.cpp:181] sdCommand(): crc error
09:46:14.356 -> [ 23465][W][sd_diskio.cpp:175] sdCommand(): no token received
09:46:14.498 -> [ 23580][W][sd_diskio.cpp:175] sdCommand(): no token received
09:46:14.590 -> [ 23689][W][sd_diskio.cpp:175] sdCommand(): no token received
09:46:14.669 -> [ 23798][W][sd_diskio.cpp:175] sdCommand(): no token received
09:46:14.778 -> [ 23907][W][sd_diskio.cpp:175] sdCommand(): no token received
09:46:14.915 -> [ 24016][W][sd_diskio.cpp:175] sdCommand(): no token received
09:46:14.996 -> [ 24125][W][sd_diskio.cpp:175] sdCommand(): no token received
09:46:15.131 -> [ 24234][W][sd_diskio.cpp:175] sdCommand(): no token received
09:46:15.213 -> [ 24343][W][sd_diskio.cpp:175] sdCommand(): no token received
09:46:15.349 -> [ 24452][W][sd_diskio.cpp:175] sdCommand(): no token received
09:46:15.431 -> [ 24561][W][sd_diskio.cpp:175] sdCommand(): no token received
09:46:15.564 -> [ 24670][W][sd_diskio.cpp:175] sdCommand(): no token received
09:46:15.687 -> [ 24779][W][sd_diskio.cpp:175] sdCommand(): no token received
09:46:15.780 -> [ 24888][W][sd_diskio.cpp:175] sdCommand(): no token received
09:46:15.868 -> [ 24997][W][sd_diskio.cpp:175] sdCommand(): no token received
09:46:15.981 -> [ 25106][W][sd_diskio.cpp:175] sdCommand(): no token received
09:46:16.119 -> [ 25215][W][sd_diskio.cpp:175] sdCommand(): no token received
09:46:16.196 -> [ 25324][W][sd_diskio.cpp:175] sdCommand(): no token received
09:46:16.305 -> [ 25433][W][sd_diskio.cpp:175] sdCommand(): no token received
09:46:16.444 -> [ 25542][W][sd_diskio.cpp:175] sdCommand(): no token received
09:46:16.522 -> [ 25651][W][sd_diskio.cpp:175] sdCommand(): no token received
09:46:16.662 -> [ 25760][W][sd_diskio.cpp:175] sdCommand(): no token received
09:46:16.740 -> [ 25869][W][sd_diskio.cpp:175] sdCommand(): no token received
09:46:16.851 -> [ 25978][W][sd_diskio.cpp:175] sdCommand(): no token received
09:46:16.988 -> [ 26087][W][sd_diskio.cpp:175] sdCommand(): no token received
09:46:17.065 -> Playing...
09:46:17.111 -> [ 26196][W][sd_diskio.cpp:181] sdCommand(): crc error
09:46:17.184 -> [ 26313][W][sd_diskio.cpp:181] sdCommand(): crc error
09:46:17.314 -> [ 26421][W][sd_diskio.cpp:181] sdCommand(): crc error
09:46:17.397 -> [ 26526][W][sd_diskio.cpp:181] sdCommand(): crc error
09:46:17.516 -> [ 26644][W][sd_diskio.cpp:181] sdCommand(): crc error
09:46:17.653 -> [ 26762][W][sd_diskio.cpp:181] sdCommand(): crc error
09:46:17.791 -> [ 26880][W][sd_diskio.cpp:181] sdCommand(): crc error
09:46:17.870 -> [ 26998][W][sd_diskio.cpp:181] sdCommand(): crc error
09:46:18.007 -> [ 27116][W][sd_diskio.cpp:181] sdCommand(): crc error
09:46:18.146 -> [ 27234][W][sd_diskio.cpp:181] sdCommand(): crc error

[pschatzmann]

I have never seen these errors, so something is not good!
What ESP32 core version are you using ?
And some additional info.

[dandeliondandy]

Thanks again.

I'm using the Audio Kit v2.2 A520 (Ai Thinker). I'll look into the DIP settings. I had the recommended, other than 1 being up/on. I'm mostly getting files, but if they seem to be the actual audio, just always very fast/compressed.

[pschatzmann]

Nop, you get the version info from the board manager: the actual version for ESP32 is 3.3.1

[dandeliondandy]

Ah, yes, sorry. That's the version I'm using. Module listed as esp32 dev module