Code: Select all
/*
WiFiTelnetToSerial - Example Transparent UART to Telnet Server for ESP32
Copyright (c) 2017 Hristo Gochkov. All rights reserved.
This file is part of the ESP32 WiFi library for Arduino environment.
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <WiFi.h>
#include <WiFiMulti.h>
WiFiMulti wifiMulti;
//how many clients should be able to telnet to this ESP32
#define MAX_SRV_CLIENTS 1
const char* ssid = "**********";
const char* password = "**********";
WiFiServer server(23);
WiFiClient serverClients[MAX_SRV_CLIENTS];
void setup() {
Serial.begin(115200);
Serial.println("\nConnecting");
wifiMulti.addAP(ssid, password);
wifiMulti.addAP("ssid_from_AP_2", "your_password_for_AP_2");
wifiMulti.addAP("ssid_from_AP_3", "your_password_for_AP_3");
Serial.println("Connecting Wifi ");
for (int loops = 10; loops > 0; loops--) {
if (wifiMulti.run() == WL_CONNECTED) {
Serial.println("");
Serial.print("WiFi connected ");
Serial.print("IP address: ");
Serial.println(WiFi.localIP());
break;
}
else {
Serial.println(loops);
delay(1000);
}
}
if (wifiMulti.run() != WL_CONNECTED) {
Serial.println("WiFi connect failed");
delay(1000);
ESP.restart();
}
//start UART and the server
Serial2.begin(9600);
server.begin();
server.setNoDelay(true);
Serial.print("Ready! Use 'telnet ");
Serial.print(WiFi.localIP());
Serial.println(" 23' to connect");
}
void loop() {
uint8_t i;
if (wifiMulti.run() == WL_CONNECTED) {
//check if there are any new clients
if (server.hasClient()){
for(i = 0; i < MAX_SRV_CLIENTS; i++){
//find free/disconnected spot
if (!serverClients[i] || !serverClients[i].connected()){
if(serverClients[i]) serverClients[i].stop();
serverClients[i] = server.available();
if (!serverClients[i]) Serial.println("available broken");
Serial.print("New client: ");
Serial.print(i); Serial.print(' ');
Serial.println(serverClients[i].remoteIP());
break;
}
}
if (i >= MAX_SRV_CLIENTS) {
//no free/disconnected spot so reject
server.available().stop();
}
}
//check clients for data
for(i = 0; i < MAX_SRV_CLIENTS; i++){
if (serverClients[i] && serverClients[i].connected()){
if(serverClients[i].available()){
//get data from the telnet client and push it to the UART
while(serverClients[i].available()) Serial2.write(serverClients[i].read());
}
}
else {
if (serverClients[i]) {
serverClients[i].stop();
}
}
}
//check UART for data
if(Serial2.available()){
size_t len = Serial2.available();
uint8_t sbuf[len];
Serial2.readBytes(sbuf, len);
//push UART data to all connected telnet clients
for(i = 0; i < MAX_SRV_CLIENTS; i++){
if (serverClients[i] && serverClients[i].connected()){
serverClients[i].write(sbuf, len);
delay(1);
}
}
}
}
else {
Serial.println("WiFi not connected!");
for(i = 0; i < MAX_SRV_CLIENTS; i++) {
if (serverClients[i]) serverClients[i].stop();
}
delay(1000);
}
}I have cobbled together the following code from TCP server example.
The problem with this code is that the Data read from the UART only seems to appear after data has been received by the server (aka recv called).
If anyone has any suggestions as to how to make it so that the UART data it written to the server immediately, it would be appreciated.
Cheers Laurence.
Code is below.
Code: Select all
/* WiFi station 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 <string.h>
#include <sys/param.h>
#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "freertos/event_groups.h"
#include "esp_system.h"
#include "esp_wifi.h"
#include "esp_event.h"
#include "esp_log.h"
#include "esp_netif.h"
#include "nvs_flash.h"
#include "driver/uart.h"
#include "driver/gpio.h"
#include <stdio.h>
#include "lwip/err.h"
#include "lwip/sockets.h"
#include "lwip/sys.h"
#include <lwip/netdb.h>
/* The examples use WiFi configuration that you can set via project configuration menu
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_ESP_WIFI_SSID "xxxxx"
#define EXAMPLE_ESP_WIFI_PASS "xxxxx"
#define EXAMPLE_ESP_MAXIMUM_RETRY 2
#define BUF_SIZE (1024)
#define UART_NUM_1 1
/* FreeRTOS event group to signal when we are connected*/
static EventGroupHandle_t s_wifi_event_group;
/* The event group allows multiple bits for each event, but we only care about two events:
* - we are connected to the AP with an IP
* - we failed to connect after the maximum amount of retries */
#define WIFI_CONNECTED_BIT BIT0
#define WIFI_FAIL_BIT BIT1
static const char *TAG = "wifi station";
static int s_retry_num = 0;
#define PORT 23
#define KEEPALIVE_IDLE 6
#define KEEPALIVE_INTERVAL 6
#define KEEPALIVE_COUNT 3
static void init_UART1(void) { //This setups UART 1 and gives it a baud rate of 115200
const int uart_num1 = UART_NUM_1;
uart_config_t uart_config1 = { //writing down the conditions of the uart.
.baud_rate = 115200,
.data_bits = UART_DATA_8_BITS,
.parity = UART_PARITY_DISABLE,
.stop_bits = UART_STOP_BITS_1,
.flow_ctrl = UART_HW_FLOWCTRL_DISABLE,
.rx_flow_ctrl_thresh = 122,
};
// We won't use a buffer for sending data.
uart_driver_install(uart_num1, BUF_SIZE * 2, BUF_SIZE * 2, 0, NULL, 0); //starting UART1 with a rx and tx buffer of 2048 with no queue and no interrupt function.
uart_param_config(uart_num1, &uart_config1); //setting the conditions of the uart according to config1
uart_set_pin(uart_num1, 22, 23, UART_PIN_NO_CHANGE, UART_PIN_NO_CHANGE); //Setup UART1 according to the default pin arrangement of ESP32
}
static void do_retransmit(const int sock) //TCP ECHO effectively.
{
int len;
int length = 0;
char rx_buffer[128];
char tx_buffer[128];
const int uart_num1 = UART_NUM_1;
u_long non_blocking=1;
int sendcnt=0;
while (1) {
//send out
ESP_ERROR_CHECK(uart_get_buffered_data_len(uart_num1, (size_t*)&length));
uart_read_bytes(uart_num1, tx_buffer, length,0);
int to_write = length;
while (to_write > 0) {
int written = send(sock, rx_buffer + (length - to_write), to_write, 0);
if (written < 0) {
ESP_LOGE(TAG, "Error occurred during sending: errno %d", errno);
}
to_write -= written;
}
write(sock, tx_buffer, length);
//len = recv(sock, rx_buffer, sizeof(rx_buffer) - 1, 0);
//if(len > 0){
// uart_write_bytes(uart_num1, rx_buffer, len);
// ESP_ERROR_CHECK(uart_get_buffered_data_len(uart_num1, (size_t*)&length));
// uart_read_bytes(uart_num1, tx_buffer, length,0);
// write(sock, tx_buffer, length);
// }
}
}
static void tcp_server_task(void *pvParameters)
{
char addr_str[128];
int addr_family = (int)pvParameters;
int ip_protocol = 0;
int keepAlive = 1;
int keepIdle = KEEPALIVE_IDLE;
int keepInterval = KEEPALIVE_INTERVAL;
int keepCount = KEEPALIVE_COUNT;
struct sockaddr_storage dest_addr;
if (addr_family == AF_INET) {
struct sockaddr_in *dest_addr_ip4 = (struct sockaddr_in *)&dest_addr;
dest_addr_ip4->sin_addr.s_addr = htonl(INADDR_ANY);
dest_addr_ip4->sin_family = AF_INET;
dest_addr_ip4->sin_port = htons(PORT);
ip_protocol = IPPROTO_IP;
}
int listen_sock = socket(addr_family, SOCK_STREAM, ip_protocol);
if (listen_sock < 0) {
ESP_LOGE(TAG, "Unable to create socket: errno %d", errno);
vTaskDelete(NULL);
return;
}
int opt = 1;
setsockopt(listen_sock, SOL_SOCKET, SO_REUSEADDR, &opt, sizeof(opt));
ESP_LOGI(TAG, "Socket created");
int err = bind(listen_sock, (struct sockaddr *)&dest_addr, sizeof(dest_addr));
if (err != 0) {
ESP_LOGE(TAG, "Socket unable to bind: errno %d", errno);
ESP_LOGE(TAG, "IPPROTO: %d", addr_family);
goto CLEAN_UP;
}
ESP_LOGI(TAG, "Socket bound, port %d", PORT);
err = listen(listen_sock, 1);
if (err != 0) {
ESP_LOGE(TAG, "Error occurred during listen: errno %d", errno);
goto CLEAN_UP;
}
while (1) {
ESP_LOGI(TAG, "Socket listening");
struct sockaddr_storage source_addr; // Large enough for both IPv4 or IPv6
socklen_t addr_len = sizeof(source_addr);
int sock = accept(listen_sock, (struct sockaddr *)&source_addr, &addr_len);
if (sock < 0) {
ESP_LOGE(TAG, "Unable to accept connection: errno %d", errno);
break;
}
// Set tcp keepalive option
// setsockopt(sock, SOL_SOCKET, SO_KEEPALIVE, &keepAlive, sizeof(int));
// setsockopt(sock, IPPROTO_TCP, TCP_KEEPIDLE, &keepIdle, sizeof(int));
// setsockopt(sock, IPPROTO_TCP, TCP_KEEPINTVL, &keepInterval, sizeof(int));
int nodelay = 1;
setsockopt(sock, IPPROTO_TCP, TCP_NODELAY, (void *)&nodelay, sizeof(int));
// setsockopt(sock, IPPROTO_TCP, TCP_KEEPCNT, &keepCount, sizeof(int));
// Convert ip address to string
if (source_addr.ss_family == PF_INET) {
inet_ntoa_r(((struct sockaddr_in *)&source_addr)->sin_addr, addr_str, sizeof(addr_str) - 1);
}
ESP_LOGI(TAG, "Socket accepted ip address: %s", addr_str);
do_retransmit(sock);
if (sock != -1) {
ESP_LOGI(TAG, "Shutting down socket and restarting...");
shutdown(sock, 0);
close(sock);
}
}
CLEAN_UP:
close(listen_sock);
vTaskDelete(NULL);
}
static void event_handler(void* arg, esp_event_base_t event_base,
int32_t event_id, void* event_data)
{
if (event_base == WIFI_EVENT && event_id == WIFI_EVENT_STA_START) {
esp_wifi_connect();
} else if (event_base == WIFI_EVENT && event_id == WIFI_EVENT_STA_DISCONNECTED) {
if (s_retry_num < EXAMPLE_ESP_MAXIMUM_RETRY) {
esp_wifi_connect();
s_retry_num++;
ESP_LOGI(TAG, "retry to connect to the AP");
} else {
xEventGroupSetBits(s_wifi_event_group, WIFI_FAIL_BIT);
}
ESP_LOGI(TAG,"connect to the AP fail");
} else if (event_base == IP_EVENT && event_id == IP_EVENT_STA_GOT_IP) {
ip_event_got_ip_t* event = (ip_event_got_ip_t*) event_data;
ESP_LOGI(TAG, "got ip:" IPSTR, IP2STR(&event->ip_info.ip));
s_retry_num = 0;
xEventGroupSetBits(s_wifi_event_group, WIFI_CONNECTED_BIT);
}
}
void wifi_init_sta(void)
{
s_wifi_event_group = xEventGroupCreate();
ESP_ERROR_CHECK(esp_netif_init());
ESP_ERROR_CHECK(esp_event_loop_create_default());
esp_netif_t *my_sta = esp_netif_create_default_wifi_sta();
esp_netif_dhcpc_stop(my_sta);
esp_netif_ip_info_t ip_info;
IP4_ADDR(&ip_info.ip, 192, 168, 2, 220);
IP4_ADDR(&ip_info.gw, 192, 168, 2, 1);
IP4_ADDR(&ip_info.netmask, 255, 255, 255, 0);
esp_netif_set_ip_info(my_sta, &ip_info);
wifi_init_config_t cfg = WIFI_INIT_CONFIG_DEFAULT();
ESP_ERROR_CHECK(esp_wifi_init(&cfg));
ESP_ERROR_CHECK(esp_event_handler_register(WIFI_EVENT, ESP_EVENT_ANY_ID, &event_handler, NULL));
ESP_ERROR_CHECK(esp_event_handler_register(IP_EVENT, IP_EVENT_STA_GOT_IP, &event_handler, NULL));
wifi_config_t wifi_config = {
.sta = {
.ssid = EXAMPLE_ESP_WIFI_SSID,
.password = EXAMPLE_ESP_WIFI_PASS
},
};
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() );
ESP_LOGI(TAG, "wifi_init_sta finished.");
/* Waiting until either the connection is established (WIFI_CONNECTED_BIT) or connection failed for the maximum
* number of re-tries (WIFI_FAIL_BIT). The bits are set by event_handler() (see above) */
EventBits_t bits = xEventGroupWaitBits(s_wifi_event_group,
WIFI_CONNECTED_BIT | WIFI_FAIL_BIT,
pdFALSE,
pdFALSE,
portMAX_DELAY);
/* xEventGroupWaitBits() returns the bits before the call returned, hence we can test which event actually
* happened. */
if (bits & WIFI_CONNECTED_BIT) {
ESP_LOGI(TAG, "connected to ap SSID:%s password:%s",
EXAMPLE_ESP_WIFI_SSID, EXAMPLE_ESP_WIFI_PASS);
} else if (bits & WIFI_FAIL_BIT) {
ESP_LOGI(TAG, "Failed to connect to SSID:%s, password:%s",
EXAMPLE_ESP_WIFI_SSID, EXAMPLE_ESP_WIFI_PASS);
} else {
ESP_LOGE(TAG, "UNEXPECTED EVENT");
}
ESP_ERROR_CHECK(esp_event_handler_unregister(IP_EVENT, IP_EVENT_STA_GOT_IP, &event_handler));
ESP_ERROR_CHECK(esp_event_handler_unregister(WIFI_EVENT, ESP_EVENT_ANY_ID, &event_handler));
vEventGroupDelete(s_wifi_event_group);
}
void app_main(void)
{
//Initialize NVS
esp_err_t ret = nvs_flash_init();
if (ret == ESP_ERR_NVS_NO_FREE_PAGES || ret == ESP_ERR_NVS_NEW_VERSION_FOUND) {
ESP_ERROR_CHECK(nvs_flash_erase());
ret = nvs_flash_init();
}
ESP_ERROR_CHECK(ret);
ESP_LOGI(TAG, "ESP_WIFI_MODE_STA");
wifi_init_sta();
init_UART1();
xTaskCreate(tcp_server_task, "tcp_server", 4096, (void*)AF_INET, 5, NULL);
}
, except, when I try to reconnect I can´t see info any more 
, added this to your code: