Skip to content
Permalink
Branch: master
Find file Copy path
Find file Copy path
2 contributors

Users who have contributed to this file

@zhouyangyale @georgcampana
77 lines (63 sloc) 1.87 KB
#include <M5StickC.h>
#include <driver/i2s.h>
#define PIN_CLK 0
#define PIN_DATA 34
#define READ_LEN (2 * 256)
#define GAIN_FACTOR 3
uint8_t BUFFER[READ_LEN] = {0};
uint16_t oldy[160];
int16_t *adcBuffer = NULL;
void i2sInit()
{
i2s_config_t i2s_config = {
.mode = (i2s_mode_t)(I2S_MODE_MASTER | I2S_MODE_RX | I2S_MODE_PDM),
.sample_rate = 44100,
.bits_per_sample = I2S_BITS_PER_SAMPLE_16BIT, // is fixed at 12bit, stereo, MSB
.channel_format = I2S_CHANNEL_FMT_ALL_RIGHT,
.communication_format = I2S_COMM_FORMAT_I2S,
.intr_alloc_flags = ESP_INTR_FLAG_LEVEL1,
.dma_buf_count = 2,
.dma_buf_len = 128,
};
i2s_pin_config_t pin_config;
pin_config.bck_io_num = I2S_PIN_NO_CHANGE;
pin_config.ws_io_num = PIN_CLK;
pin_config.data_out_num = I2S_PIN_NO_CHANGE;
pin_config.data_in_num = PIN_DATA;
i2s_driver_install(I2S_NUM_0, &i2s_config, 0, NULL);
i2s_set_pin(I2S_NUM_0, &pin_config);
i2s_set_clk(I2S_NUM_0, 44100, I2S_BITS_PER_SAMPLE_16BIT, I2S_CHANNEL_MONO);
}
void mic_record_task (void* arg)
{
size_t bytesread;
while(1){
i2s_read(I2S_NUM_0,(char*) BUFFER, READ_LEN, &bytesread, (100 / portTICK_RATE_MS));
adcBuffer = (int16_t *)BUFFER;
showSignal();
vTaskDelay(100 / portTICK_RATE_MS);
}
}
void setup() {
M5.begin();
M5.Lcd.setRotation(3);
M5.Lcd.fillScreen(WHITE);
M5.Lcd.setTextColor(BLACK, WHITE);
M5.Lcd.println("mic test");
i2sInit();
xTaskCreate(mic_record_task, "mic_record_task", 2048, NULL, 1, NULL);
}
void showSignal(){
int y;
for (int n = 0; n < 160; n++){
y = adcBuffer[n] * GAIN_FACTOR;
y = map(y, INT16_MIN, INT16_MAX, 10, 70);
M5.Lcd.drawPixel(n, oldy[n],WHITE);
M5.Lcd.drawPixel(n,y,BLACK);
oldy[n] = y;
}
}
void loop() {
printf("loop cycling\n");
vTaskDelay(1000 / portTICK_RATE_MS); // otherwise the main task wastes half of the cpu cycles
}
You can’t perform that action at this time.