ESP8266学习二---SOCKET-TCP_CLIENT

    上次学习了wifi热点信息扫描的东西。本次测试学习下tcp client的内容。

    全部源码如下：

/* BSD Socket API 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 
#include 
#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "freertos/event_groups.h"
#include "esp_system.h"
#include "esp_wifi.h"
#include "esp_event_loop.h"
#include "esp_log.h"
#include "nvs_flash.h"

#include "lwip/err.h"
#include "lwip/sockets.h"
#include "lwip/sys.h"
#include 


/* The examples use simple WiFi configuration that you can set via
   'make menuconfig'.
   If you'd rather not, just change the below entries to strings with
   the config you want - ie #define EXAMPLE_WIFI_SSID "mywifissid"
*/

#define EXAMPLE_WIFI_SSID CONFIG_WIFI_SSID
#define EXAMPLE_WIFI_PASS CONFIG_WIFI_PASSWORD

#ifdef CONFIG_EXAMPLE_IPV4
#define HOST_IP_ADDR CONFIG_EXAMPLE_IPV4_ADDR
#else
#define HOST_IP_ADDR CONFIG_EXAMPLE_IPV6_ADDR
#endif

#define PORT CONFIG_EXAMPLE_PORT

/* FreeRTOS event group to signal when we are connected & ready to make a request */
static EventGroupHandle_t wifi_event_group;

const int IPV4_GOTIP_BIT = BIT0;
#ifdef CONFIG_EXAMPLE_IPV6
const int IPV6_GOTIP_BIT = BIT1;
#endif


static const char *TAG = "tcp_client";
static const char *payload = "Message from ESP8266 ";

static esp_err_t event_handler(void *ctx, system_event_t *event)
{
    switch (event->event_id) {
    case SYSTEM_EVENT_STA_START:
        esp_wifi_connect();
        ESP_LOGI(TAG, "SYSTEM_EVENT_STA_START");
        break;
    case SYSTEM_EVENT_STA_CONNECTED:
#ifdef CONFIG_EXAMPLE_IPV6
        /* enable ipv6 */
        tcpip_adapter_create_ip6_linklocal(TCPIP_ADAPTER_IF_STA);
#endif
        break;
    case SYSTEM_EVENT_STA_GOT_IP:
        xEventGroupSetBits(wifi_event_group, IPV4_GOTIP_BIT);
        ESP_LOGI(TAG, "SYSTEM_EVENT_STA_GOT_IP");
        break;
    case SYSTEM_EVENT_STA_DISCONNECTED:
        /* This is a workaround as ESP32 WiFi libs don't currently auto-reassociate. */
        esp_wifi_connect();
        xEventGroupClearBits(wifi_event_group, IPV4_GOTIP_BIT);
#ifdef CONFIG_EXAMPLE_IPV6
        xEventGroupClearBits(wifi_event_group, IPV6_GOTIP_BIT);
#endif
        break;
    case SYSTEM_EVENT_AP_STA_GOT_IP6:
#ifdef CONFIG_EXAMPLE_IPV6
        xEventGroupSetBits(wifi_event_group, IPV6_GOTIP_BIT);
        ESP_LOGI(TAG, "SYSTEM_EVENT_STA_GOT_IP6");

        char *ip6 = ip6addr_ntoa(&event->event_info.got_ip6.ip6_info.ip);
        ESP_LOGI(TAG, "IPv6: %s", ip6);
#endif
    default:
        break;
    }
    return ESP_OK;
}



static void initialise_wifi(void)
{
    tcpip_adapter_init();
    wifi_event_group = xEventGroupCreate();
    ESP_ERROR_CHECK( esp_event_loop_init(event_handler, NULL) );
    wifi_init_config_t cfg = WIFI_INIT_CONFIG_DEFAULT();
    ESP_ERROR_CHECK( esp_wifi_init(&cfg) );
    ESP_ERROR_CHECK( esp_wifi_set_storage(WIFI_STORAGE_RAM) );
    wifi_config_t wifi_config = {
        .sta = {
            .ssid = EXAMPLE_WIFI_SSID,
            .password = EXAMPLE_WIFI_PASS,
        },
    };
    ESP_LOGI(TAG, "Setting WiFi configuration SSID %s...", wifi_config.sta.ssid);
    ESP_ERROR_CHECK( esp_wifi_set_mode(WIFI_MODE_STA) );
	ESP_ERROR_CHECK( esp_wifi_set_config(ESP_IF_WIFI_STA, &wifi_config) );
    ESP_ERROR_CHECK( esp_wifi_start() );

	
}

static void wait_for_ip()
{
#ifdef CONFIG_EXAMPLE_IPV6
    uint32_t bits = IPV4_GOTIP_BIT | IPV6_GOTIP_BIT;
#else
    uint32_t bits = IPV4_GOTIP_BIT;
#endif

    ESP_LOGI(TAG, "Waiting for AP connection...");
    xEventGroupWaitBits(wifi_event_group, bits, false, true, portMAX_DELAY);
    ESP_LOGI(TAG, "Connected to AP");
}


static void tcp_client_task(void *pvParameters)
{
    char rx_buffer[512];
    char addr_str[128];
    int addr_family;
    int ip_protocol;

    while (1) {

#ifdef CONFIG_EXAMPLE_IPV4
        struct sockaddr_in destAddr;
        destAddr.sin_addr.s_addr = inet_addr(HOST_IP_ADDR);
        destAddr.sin_family = AF_INET;
        destAddr.sin_port = htons(PORT);
        addr_family = AF_INET;
        ip_protocol = IPPROTO_IP;
        inet_ntoa_r(destAddr.sin_addr, addr_str, sizeof(addr_str) - 1);
        ESP_LOGI(TAG, "HOST_IP_ADDR: %s, %d", HOST_IP_ADDR, PORT);
#else // IPV6
        struct sockaddr_in6 destAddr;
        inet6_aton(HOST_IP_ADDR, &destAddr.sin6_addr);
        destAddr.sin6_family = AF_INET6;
        destAddr.sin6_port = htons(PORT);
        addr_family = AF_INET6;
        ip_protocol = IPPROTO_IPV6;
        inet6_ntoa_r(destAddr.sin6_addr, addr_str, sizeof(addr_str) - 1);
#endif

        int sock =  socket(addr_family, SOCK_STREAM, ip_protocol);
        if (sock < 0) {
            ESP_LOGE(TAG, "Unable to create socket: errno %d", errno);
			vTaskDelay(2000 / portTICK_PERIOD_MS);
            continue;
        }
        ESP_LOGI(TAG, "Socket created");

        int err = connect(sock, (struct sockaddr *)&destAddr, sizeof(destAddr));
        if (err != 0) {
            ESP_LOGE(TAG, "Socket unable to connect: errno %d", errno);
        }
        ESP_LOGI(TAG, "Successfully connected");

        while (1) {
            int err = send(sock, payload, strlen(payload), 0);
            if (err < 0) {
                ESP_LOGE(TAG, "Error occured during sending: errno %d", errno);
                break;
            }

            int len = recv(sock, rx_buffer, sizeof(rx_buffer) - 1, 0);
            // Error occured during receiving
            if (len < 0) {
                ESP_LOGE(TAG, "recv failed: errno %d", errno);
                break;
            }
            // Data received
            else {
                rx_buffer[len] = 0; // Null-terminate whatever we received and treat like a string
                ESP_LOGI(TAG, "Received %d bytes from %s:", len, addr_str);
                ESP_LOGI(TAG, "%s", rx_buffer);
            }

            //vTaskDelay(2000 / portTICK_PERIOD_MS);
            vTaskDelay(2000 / 200);
        }

        if (sock != -1) {
            ESP_LOGE(TAG, "Shutting down socket and restarting...");
            shutdown(sock, 0);
            close(sock);
        }
    }
    vTaskDelete(NULL);
}

void app_main()
{
    ESP_ERROR_CHECK( nvs_flash_init() );
    initialise_wifi();
    wait_for_ip();

    xTaskCreate(tcp_client_task, "tcp_client", 4096, NULL, 5, NULL);
}

大致流程为：

  一、 配置系统make menuconfig

  1. 设置串口信息Serial flasher config  ---> 

   串口号、 (/dev/ttyUSB0) Default serial port（这里根据实际情况配置，我的ttyUSB0）

  配置波特率、Default baud rate (115200 baud)

 配置SPI烧录模式Flash SPI mode (DOUT)、速率Flash SPI speed (40 MHz) 、大小Flash size (4 MB)

 配置monitor波特率'make monitor' baud rate (115200 bps)

2. 配置范例选项Example Configuration-->里面有SSID、passwd、tcpserver的地址和端口 等。

3.配置8266的CPU频率等信息Component config  --->ESP8266-specific  ---> CPU frequency (80 MHz)  ---> 尤其是 (115200) UART console baud rate这个选项，要不有可能串口调试乱码

 

二、编译下载调试

如果顺利的话 就能通过PC与8266进行通信了。