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#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "freertos/queue.h"
#include "driver/rmt.h"
#include "driver/periph_ctrl.h"
#include "soc/rmt_reg.h"

void app_main()
{
	rmt_config_t rmt_rx =
	{
		.channel = 0,
		.gpio_num = 17,
		.clk_div = 80, //1MHz
		.mem_block_num = 1,
		.rmt_mode = RMT_MODE_RX,
		.rx_config.filter_en = true,
		.rx_config.filter_ticks_thresh = 100,
		.rx_config.idle_threshold = 9500
	};

	rmt_config(&rmt_rx);
	rmt_driver_install(rmt_rx.channel, 1000, 0);
	RingbufHandle_t rb = NULL;
	rmt_get_ringbuf_handle(rmt_rx.channel, &rb);
	rmt_rx_start(rmt_rx.channel, 1);

	while(rb)
	{
		size_t rx_size = 0;
		rmt_item32_t* item = (rmt_item32_t*) xRingbufferReceive(rb, &rx_size, 1000);
		if(item)
		{
			for (int i = 0; i < rx_size>>2; i++)
			{
				printf("%d:%dus %d:%dus\n", (item+i)->level0, (item+i)->duration0, (item+i)->level1, (item+i)->duration1);
			}
			vRingbufferReturnItem(rb, (void*) item);
		}
		else
		{
			break;
		}
	}
}

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E (2016) rmt: RMT[0] ERR
E (2016) rmt: status: 0x13000040

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E (1014) rmt: RMT[0] ERR
E (1014) rmt: status: 0x13000040

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#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "freertos/queue.h"
#include "driver/rmt.h"
#include "driver/periph_ctrl.h"
#include "soc/rmt_reg.h"

void app_main()
{
    rmt_config_t rmt_rx =
	{
		.channel = 0,
		.gpio_num = 18,
		.clk_div = 80, //1MHz
		.mem_block_num = 1,
		.rmt_mode = RMT_MODE_RX,
		.rx_config.filter_en = true,
		.rx_config.filter_ticks_thresh = 255,
		.rx_config.idle_threshold = 65535
	};
	rmt_config(&rmt_rx);
	while (1)
	{
		rmt_rx_start(rmt_rx.channel, 1);
		vTaskDelay(100 / portTICK_PERIOD_MS);
		rmt_item32_t* item = (rmt_item32_t*) (RMT_CHANNEL_MEM(rmt_rx.channel));
		printf("high %dus | ", (item)->level0*(item)->duration0 + (item)->level1*(item)->duration1);
		printf("low %dus\n", !(item)->level0*(item)->duration0 + !(item)->level1*(item)->duration1);
	}
}

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    rmt_config_t rmt_rx =
	{
		.channel = 0,
		.gpio_num = INPUT,
		.clk_div = 80, //1MHz
		.mem_block_num = BUFS,
		.rmt_mode = RMT_MODE_RX,
		.rx_config = {.filter_en = true, .filter_ticks_thresh = 255, .idle_threshold = 30000}
	};
    rmt_config(&rmt_rx);
	rmt_item32_t* item = (rmt_item32_t*)(RMT_CHANNEL_MEM(rmt_rx.channel));
	item->val=-1;
	rmt_rx_start(rmt_rx.channel, 1);

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		while (item->val==-1)
		{
			if (RMT.status_ch[rmt_rx.channel]==0x04000000){
				//overflow action
			}
		}

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		for(i = 0; i < (uint8_t)RMT.status_ch[rmt_rx.channel]; i++)
		{
			lowus = !(item+i)->level0*(item+i)->duration0 + !(item+i)->level1*(item+i)->duration1;
			highus = (item+i)->level0*(item+i)->duration0 + (item+i)->level1*(item+i)->duration1;
			items++;
			//do something with pulse widths
		}

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		if (items)
		{
			item->val=-1;
			rmt_memory_rw_rst(rmt_rx.channel);
		}