ESP32 官方的 USB 框架是 TinyUSB, 这次带来的是使用 TinyUSB 在 IDF 下实现的虚拟USB麦克风。
代码内置了一个正弦波的采样数据，录音机打开之后会送出：
/*
* SPDX-FileCopyrightText: 2024 Espressif Systems (Shanghai) CO LTD
*
* SPDX-License-Identifier: Unlicense OR CC0-1.0
*/
#include <stdio.h>
#include <math.h>
#include "sdkconfig.h"
#include "esp_err.h"
#include "esp_log.h"
#include "driver/uart.h"
#include "usb_device_uac.h"
#include "sine.h"
static const char *TAG = "usb_uac_main";
int audiobuffer=0;
static esp_err_t uac_device_output_cb(uint8_t *buf, size_t len, void *arg)
{
//size_t bytes_written = 0;
//bsp_extra_i2s_write(buf, len, &bytes_written, 0);
ESP_LOGE(TAG, "ocb");
return ESP_OK;
}
static esp_err_t uac_device_input_cb(uint8_t *buf, size_t len, size_t *bytes_read, void *arg)
{
for (int i=0;i<len;i++) {
buf[i]=AudioData[(audiobuffer+i)%AUDIOLEN];
}
audiobuffer=(audiobuffer+len)%AUDIOLEN;
ESP_LOGE(TAG, "icb");
*bytes_read=len;
return ESP_OK;
}
static void uac_device_set_mute_cb(uint32_t mute, void *arg)
{
ESP_LOGI(TAG, "uac_device_set_mute_cb: %"PRIu32"", mute);
//bsp_extra_codec_mute_set(mute);
}
static void uac_device_set_volume_cb(uint32_t volume, void *arg)
{
ESP_LOGI(TAG, "uac_device_set_volume_cb: %"PRIu32"", volume);
//bsp_extra_codec_volume_set(volume, NULL);
}
void app_main(void)
{
uart_config_t uart_config = {
.baud_rate = 2000000,
.data_bits = UART_DATA_8_BITS,
.parity= UART_PARITY_DISABLE,
.stop_bits=UART_STOP_BITS_1
};
uart_param_config(UART_NUM_0,&uart_config);
uac_device_config_t config = {
.output_cb = uac_device_output_cb,
.input_cb = uac_device_input_cb,
.set_mute_cb = uac_device_set_mute_cb,
.set_volume_cb = uac_device_set_volume_cb,
.cb_ctx = NULL,
};
uac_device_init(&config);
}
工作的视频
完整的代码
