esp32, UART テスト編 (UART2)

esp32 の３系統あるらしき、UART を使ってみようと思います。
*) 今回は、UART2 のみ使用しています。

#
example / uart_echoを参考にしています。
ＴＸ入力信号を、ループバック　する動作らしいです。

*) 入力コードが、 RXに出力されます。

ドライバ書込み後、 #16 #17 に、 FTDI  UARTアダプタ接続
して、動作確認しています。


# 配線

esp32	FTDI
#16(TX)	RX
#17(RX)	TX
#18(RTS)	CTS
#19(CTS)	RTS

# code

	/* Uart Events Example
	This example code is in the Public Domain (or CC0 licensed, at your option.)
	Unless required by applicable law or agreed to in writing, this
	software is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
	CONDITIONS OF ANY KIND, either express or implied.
	*/
	#include <stdio.h>
	#include <string.h>
	#include <stdlib.h>
	#include "freertos/FreeRTOS.h"
	#include "freertos/task.h"
	#include "esp_system.h"
	#include "nvs_flash.h"
	#include "driver/uart.h"
	#include "freertos/queue.h"
	#include "esp_log.h"
	#include "soc/uart_struct.h"
	/**
	* This is a example exaple which echos any data it receives on UART1 back to the sender, with hardware flow control
	* turned on. It does not use UART driver event queue.
	*
	* - port: UART1
	* - rx buffer: on
	* - tx buffer: off
	* - flow control: on
	* - event queue: off
	* - pin assignment: txd(io4), rxd(io5), rts(18), cts(19)
	*/
	//#define ECHO_TEST_TXD (4)
	//#define ECHO_TEST_RXD (5)
	#define ECHO_TEST_TXD (16)
	#define ECHO_TEST_RXD (17)
	#define ECHO_TEST_RTS (18)
	#define ECHO_TEST_CTS (19)
	#define BUF_SIZE (1024)
	//an example of echo test with hardware flow control on UART1
	static void echo_task()
	{
	// const int uart_num = UART_NUM_1;
	const int uart_num = UART_NUM_2;
	uart_config_t uart_config = {
	.baud_rate = 115200,
	.data_bits = UART_DATA_8_BITS,
	.parity = UART_PARITY_DISABLE,
	.stop_bits = UART_STOP_BITS_1,
	.flow_ctrl = UART_HW_FLOWCTRL_CTS_RTS,
	.rx_flow_ctrl_thresh = 122,
	};
	//Configure UART1 parameters
	uart_param_config(uart_num, &uart_config);
	//Set UART1 pins(TX: IO4, RX: I05, RTS: IO18, CTS: IO19)
	uart_set_pin(uart_num, ECHO_TEST_TXD, ECHO_TEST_RXD, ECHO_TEST_RTS, ECHO_TEST_CTS);
	//Install UART driver (we don't need an event queue here)
	//In this example we don't even use a buffer for sending data.
	uart_driver_install(uart_num, BUF_SIZE * 2, 0, 0, NULL, 0);
	uint8_t* data = (uint8_t*) malloc(BUF_SIZE);
	while(1) {
	//Read data from UART
	int len = uart_read_bytes(uart_num, data, BUF_SIZE, 20 / portTICK_RATE_MS);
	//Write data back to UART
	uart_write_bytes(uart_num, (const char*) data, len);
	}
	}
	void app_main()
	{
	//A uart read/write example without event queue;
	xTaskCreate(echo_task, "uart_echo_task", 1024, NULL, 10, NULL);
	}

view raw uart_echo_example_main.c hosted with ❤ by GitHub

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# 関連の esp32まとめ
http://kuc-arc-f.com/make/?p=1288