ESP32的I2S_ADC_DAC速率不一样是怎么回事？

IDF版本5.0，硬件ESP32

我在componentsdriveri2s.c里增加2个变量

volatile int i2s_rx_count = 0;

volatile int i2s_tx_count = 0;

在static void IRAM_ATTR i2s_intr_handler_default(void *arg)中

在if ((status & I2S_INTR_OUT_EOF) && p_i2s->tx) 中i2s_tx_count++;

在if ((status & I2S_INTR_IN_SUC_EOF) && p_i2s->rx) 中i2s_rx_count++;





然后在examplesperipheralsi2si2s_adc_dac的main中注释了xTaskCreate(adc_read_task, "ADC read task", 2048, NULL, 5, NULL);防止该线程影响测试，

在i2s_adc_enable(EXAMPLE_I2S_NUM);后每隔一秒打印一次i2s_tx_count和i2s_rx_count





I (1351) ad/da: i2s_rx_count = 31

I (1351) ad/da: i2s_tx_count = 31

I (2351) ad/da: i2s_rx_count = 62

I (2351) ad/da: i2s_tx_count = 62

I (3351) ad/da: i2s_rx_count = 93

I (3351) ad/da: i2s_tx_count = 94

I (4351) ad/da: i2s_rx_count = 124

I (4351) ad/da: i2s_tx_count = 125

I (5351) ad/da: i2s_rx_count = 155

I (5351) ad/da: i2s_tx_count = 156

I (6351) ad/da: i2s_rx_count = 186

I (6351) ad/da: i2s_tx_count = 187

I (7351) ad/da: i2s_rx_count = 217

I (7351) ad/da: i2s_tx_count = 219

I (8351) ad/da: i2s_rx_count = 248

I (8351) ad/da: i2s_tx_count = 250

I (9351) ad/da: i2s_rx_count = 279

I (9351) ad/da: i2s_tx_count = 281

I (10351) ad/da: i2s_rx_count = 310

I (10351) ad/da: i2s_tx_count = 312

I (11351) ad/da: i2s_rx_count = 341

I (11351) ad/da: i2s_tx_count = 344

I (12351) ad/da: i2s_rx_count = 372

I (12351) ad/da: i2s_tx_count = 375

I (13351) ad/da: i2s_rx_count = 403

I (13351) ad/da: i2s_tx_count = 406

I (14351) ad/da: i2s_rx_count = 434

I (14351) ad/da: i2s_tx_count = 438

I (15351) ad/da: i2s_rx_count = 465

I (15351) ad/da: i2s_tx_count = 469

I (16351) ad/da: i2s_rx_count = 496

I (16351) ad/da: i2s_tx_count = 500

I (17351) ad/da: i2s_rx_count = 527

I (17351) ad/da: i2s_tx_count = 531

I (18351) ad/da: i2s_rx_count = 558

I (18351) ad/da: i2s_tx_count = 563

I (19351) ad/da: i2s_rx_count = 589

I (19351) ad/da: i2s_tx_count = 594

I (20351) ad/da: i2s_rx_count = 620

I (20351) ad/da: i2s_tx_count = 625

I (21351) ad/da: i2s_rx_count = 651

I (21351) ad/da: i2s_tx_count = 657

I (22351) ad/da: i2s_rx_count = 682

I (22351) ad/da: i2s_tx_count = 688





RX和TX的计数差距随时间增加会误差越大，





如果在I2S_basic中测试RX和TX的计数就没有误差，偶尔误差1应该是打印的间隔误差