esp32 SPIFFS support

README.md

@@ -14,8 +14,8 @@
 ![WiringMax9814](doc/wiring_MAX9814.jpg)
 The SD card wiring is the same as above (for my sd card adapter, pullup resistors weren't necessary)
 
-MAX9814 Wiring:
-MAX9814 |   ESP32
+MAX9814 Wiring:  
+MAX9814 |   ESP32  
 GND - GND  
 Vdd - 3V3  
 Out - VP (GPIO36)  

esp32_I2S_recorder_SPIFFS/I2S.cpp

@@ -0,0 +1,44 @@
+#include "I2S.h"
+
+void I2S_Init(i2s_mode_t MODE, i2s_bits_per_sample_t BPS) {
+  i2s_config_t i2s_config = {
+    .mode = (i2s_mode_t)(I2S_MODE_MASTER | I2S_MODE_RX | I2S_MODE_TX | I2S_MODE_DAC_BUILT_IN | I2S_MODE_ADC_BUILT_IN),
+    .sample_rate = SAMPLE_RATE,
+    .bits_per_sample = BPS,
+    .channel_format = I2S_CHANNEL_FMT_RIGHT_LEFT,
+    .communication_format = (i2s_comm_format_t)(I2S_COMM_FORMAT_I2S | I2S_COMM_FORMAT_I2S_MSB),
+    .intr_alloc_flags = 0,
+    .dma_buf_count = 16,
+    .dma_buf_len = 60
+  };
+  if (MODE == I2S_MODE_RX || MODE == I2S_MODE_TX) {
+    i2s_pin_config_t pin_config;
+    Serial.println("using i2c_RX_TX");
+    pin_config.bck_io_num = PIN_I2S_BCLK;
+    pin_config.ws_io_num = PIN_I2S_LRC;
+    if (MODE == I2S_MODE_RX) {
+      pin_config.data_out_num = I2S_PIN_NO_CHANGE;
+      pin_config.data_in_num = PIN_I2S_DIN;
+    } else if (MODE == I2S_MODE_TX) {
+      pin_config.data_out_num = PIN_I2S_DOUT;
+      pin_config.data_in_num = I2S_PIN_NO_CHANGE;
+    }
+
+    i2s_driver_install(I2S_NUM_0, &i2s_config, 0, NULL);
+    i2s_set_pin(I2S_NUM_0, &pin_config);
+    i2s_set_clk(I2S_NUM_0, SAMPLE_RATE, BPS, I2S_CHANNEL_STEREO);
+  } else if (MODE == I2S_MODE_DAC_BUILT_IN || MODE == I2S_MODE_ADC_BUILT_IN) {
+    Serial.println("using ADC_builtin");
+    i2s_driver_install(I2S_NUM_0, &i2s_config, 0, NULL);
+    // GPIO36, VP
+    i2s_set_adc_mode(ADC_UNIT_1, ADC1_CHANNEL_0);
+  }
+}
+
+int I2S_Read(char *data, int numData) {
+  return i2s_read_bytes(I2S_NUM_0, (char *)data, numData, portMAX_DELAY);
+}
+
+void I2S_Write(char *data, int numData) {
+  i2s_write_bytes(I2S_NUM_0, (const char *)data, numData, portMAX_DELAY);
+}

esp32_I2S_recorder_SPIFFS/I2S.h

@@ -0,0 +1,38 @@
+#include <Arduino.h>
+#include "freertos/FreeRTOS.h"
+#include "freertos/task.h"
+#include "driver/i2s.h"
+#include "esp_system.h"
+#define SAMPLE_RATE (44100)
+#define PIN_I2S_BCLK 26
+#define PIN_I2S_LRC 22
+#define PIN_I2S_DIN 34
+#define PIN_I2S_DOUT 25
+
+// This I2S specification : 
+//  -   LRC high is channel 2 (right).
+//  -   LRC signal transitions once each word.
+//  -   DATA is valid on the CLOCK rising edge.
+//  -   Data bits are MSB first.
+//  -   DATA bits are left-aligned with respect to LRC edge.
+//  -   DATA bits are right-shifted by one with respect to LRC edges.
+//        It's valid for ADMP441 (microphone) and MAX98357A (speaker). 
+//        It's not valid for SPH0645LM4H(microphone) and WM8960(microphon/speaker).
+//
+//  -   44100Hz
+//  -   stereo
+
+/// @parameter MODE : I2S_MODE_RX or I2S_MODE_TX
+/// @parameter BPS : I2S_BITS_PER_SAMPLE_16BIT or I2S_BITS_PER_SAMPLE_32BIT
+void I2S_Init(i2s_mode_t MODE, i2s_bits_per_sample_t BPS);
+
+/// I2S_Read() for I2S_MODE_RX
+/// @parameter data: pointer to buffer
+/// @parameter numData: buffer size
+/// @return Number of bytes read
+int I2S_Read(char* data, int numData);
+
+/// I2S_Write() for I2S_MODE_TX
+/// @param data: pointer to buffer
+/// @param numData: buffer size
+void I2S_Write(char* data, int numData);

esp32_I2S_recorder_SPIFFS/Wav.cpp

@@ -0,0 +1,50 @@
+#include "Wav.h"
+
+void CreateWavHeader(byte* header, int waveDataSize){
+  header[0] = 'R';
+  header[1] = 'I';
+  header[2] = 'F';
+  header[3] = 'F';
+  unsigned int fileSizeMinus8 = waveDataSize + 44 - 8;
+  header[4] = (byte)(fileSizeMinus8 & 0xFF);
+  header[5] = (byte)((fileSizeMinus8 >> 8) & 0xFF);
+  header[6] = (byte)((fileSizeMinus8 >> 16) & 0xFF);
+  header[7] = (byte)((fileSizeMinus8 >> 24) & 0xFF);
+  header[8] = 'W';
+  header[9] = 'A';
+  header[10] = 'V';
+  header[11] = 'E';
+  header[12] = 'f';
+  header[13] = 'm';
+  header[14] = 't';
+  header[15] = ' ';
+  header[16] = 0x10;  // linear PCM
+  header[17] = 0x00;
+  header[18] = 0x00;
+  header[19] = 0x00;
+  header[20] = 0x01;  // linear PCM
+  header[21] = 0x00;
+  header[22] = 0x01;  // monoral
+  header[23] = 0x00;
+  header[24] = 0x44;  // sampling rate 44100
+  header[25] = 0xAC;
+  header[26] = 0x00;
+  header[27] = 0x00;
+  header[28] = 0x88;  // Byte/sec = 44100x2x1 = 88200
+  header[29] = 0x58;
+  header[30] = 0x01;
+  header[31] = 0x00;
+  header[32] = 0x02;  // 16bit monoral
+  header[33] = 0x00;
+  header[34] = 0x10;  // 16bit
+  header[35] = 0x00;
+  header[36] = 'd';
+  header[37] = 'a';
+  header[38] = 't';
+  header[39] = 'a';
+  header[40] = (byte)(waveDataSize & 0xFF);
+  header[41] = (byte)((waveDataSize >> 8) & 0xFF);
+  header[42] = (byte)((waveDataSize >> 16) & 0xFF);
+  header[43] = (byte)((waveDataSize >> 24) & 0xFF);
+}
+

esp32_I2S_recorder_SPIFFS/Wav.h

@@ -0,0 +1,4 @@
+#include <Arduino.h>
+
+// 16bit, monoral, 44100Hz,  linear PCM
+void CreateWavHeader(byte* header, int waveDataSize);  // size of header is 44

esp32_I2S_recorder_SPIFFS/esp32_I2S_recorder_SPIFFS.ino

@@ -0,0 +1,87 @@
+#include "Arduino.h"
+#include <FS.h>
+#include "Wav.h"
+#include "I2S.h"
+#include "SPIFFS.h"
+#define FORMAT_SPIFFS_IF_FAILED true
+
+//comment the first line and uncomment the second if you use MAX9814
+//#define I2S_MODE I2S_MODE_RX
+#define I2S_MODE I2S_MODE_ADC_BUILT_IN
+
+const int record_time = 5;  // second
+const char filename[] = "/sound.wav";
+
+const int headerSize = 44;
+const int waveDataSize = record_time * 88000;
+const int numCommunicationData = 8000;
+const int numPartWavData = numCommunicationData/4;
+byte header[headerSize];
+char communicationData[numCommunicationData];
+char partWavData[numPartWavData];
+File file;
+
+//https://github.com/espressif/arduino-esp32/blob/master/libraries/SPIFFS/examples/SPIFFS_Test/SPIFFS_Test.ino
+void listDir(fs::FS& fs, const char* dirname, uint8_t levels) {
+  // Serial.printf("Listing directory: %s\r\n", dirname);
+
+  File root = fs.open(dirname);
+  if (!root) {
+    // Serial.println("- failed to open directory");
+    return;
+  }
+  if (!root.isDirectory()) {
+    // Serial.println(" - not a directory");
+    return;
+  }
+
+  File file = root.openNextFile();
+  while (file) {
+    if (file.isDirectory()) {
+      Serial.print("  DIR : ");
+      Serial.println(file.name());
+      if (levels) {
+        listDir(fs, file.name(), levels - 1);
+      }
+    } else {
+      Serial.print("  FILE: ");
+      Serial.print(file.name());
+      Serial.print("\tSIZE: ");
+      Serial.println(file.size());
+    }
+    file = root.openNextFile();
+  }
+}
+
+void setup() {
+  Serial.begin(115200);
+  if (!SPIFFS.begin(FORMAT_SPIFFS_IF_FAILED)) {
+    Serial.println("SPIFFS Mount Failed");
+    return;
+  }
+  // https://gitter.im/espressif/arduino-esp32?at=5dffa2c7260751301cf1455b
+  // do NOT remove the following line  SPIFFS.format();
+  CreateWavHeader(header, waveDataSize);
+  SPIFFS.remove(filename);
+  file = SPIFFS.open(filename, FILE_WRITE);
+  if (!file) return;
+  Serial.println("start recording");
+  file.write(header, headerSize);
+  I2S_Init(I2S_MODE, I2S_BITS_PER_SAMPLE_32BIT);
+  for (int j = 0; j < waveDataSize/numPartWavData; ++j) {
+    I2S_Read(communicationData, numCommunicationData);
+    for (int i = 0; i < numCommunicationData/8; ++i) {
+      partWavData[2*i] = communicationData[8*i + 2];
+      partWavData[2*i + 1] = communicationData[8*i + 3];
+    }
+    file.write((const byte*)partWavData, numPartWavData);
+  }
+  file.close();
+  Serial.println("finish recording");
+  Serial.println("test SPIFFS recording file");
+  listDir(SPIFFS, "/", 0);
+
+}
+
+void loop() {
+}