Example 520 TCP Simple

Table of Contents

• Connecting with PuTTY (Windows)
• Connecting with Telnet (Linux/Unix/Mac)
• Whole Code

Finally, let's quickly go over communication via TCP sockets. This is very similar to the WebSocket implementation, with one key difference: you'll need a separate application on the client side to access the TCP socket.

On Windows, the recommended application is PuTTY, while on Linux and Mac, you can use the built-in telnet terminal application. Instructions on how to install and configure these tools can be found in the installation section.

Connecting with PuTTY (Windows)

To connect to your device using PuTTY, you'll need the device's IP address and the port number. The IP address varies per device, but for TCP connections, the standard port is usually 23.

PuTTY Config

Connecting with Telnet (Linux/Unix/Mac)

On Linux, Unix, or macOS, you can use the following command in the terminal:

telnet <ip> <port>

For example:

telnet 192.168.0.160 23

One tricky part with telnet is exiting the session. To do so, press CTRL + ], which will bring up the Telnet command prompt. Then type quit and press Enter to close the connection.

Whole Code

/*
 * Created on Aug 10 2020
 *
 * Copyright (c) 2023 - Daniel Hajnal
 * hajnal.daniel96@gmail.com
 * This file is part of the Shellminator project.
 * Modified 2023.05.13
*/
 
#include "Shellminator.hpp"
#include "Shellminator-TcpSocket.hpp"
 
#define TCP_PORT 23
 
char ssid[] = "Replace With Your SSID";        // your network SSID (name)
char pass[] = "Replace With Your Password";    // your network password (use for WPA, or use as key for WEP)
 
// We will need a buffer to avoid flickering.
uint8_t printBuffer[ 100 ];
int printBufferSize = sizeof( printBuffer );
 
ShellminatorTcpSocket tcp( TCP_PORT );
 
// Create a Shellminator object, and initialize it to use WebSocketsServer
Shellminator shell( &tcp );
 
// Hash for 'Password' as password. Obviously, replace it
// when working on something sensitive.
uint8_t passwordHash[] = { 0xCC, 0xb4, 0x24, 0x83 };
 
// Shellminator logo.
const char logo[] =
 
"   _____ __         ____          _             __            \r\n"
"  / ___// /_  ___  / / /___ ___  (_)___  ____ _/ /_____  _____\r\n"
"  \\__ \\/ __ \\/ _ \\/ / / __ `__ \\/ / __ \\/ __ `/ __/ __ \\/ ___/\r\n"
" ___/ / / / /  __/ / / / / / / / / / / / /_/ / /_/ /_/ / /    \r\n"
"/____/_/ /_/\\___/_/_/_/ /_/ /_/_/_/ /_/\\__,_/\\__/\\____/_/     \r\n"
"\r\n\033[0;37m"
"Visit on GitHub:\033[1;32m https://github.com/dani007200964/Shellminator\r\n\r\n"
 
;
 
// System init section.
void setup(){
 
    Serial.begin(115200);
 
    WiFi.begin(ssid, pass);
 
    // Attempt to connect to WiFi network:
    Serial.print("Attempting to connect to Network");
    while( WiFi.status() != WL_CONNECTED ){
        Serial.print( '.' );
        delay( 1000 );
    }
    Serial.print("Connected!");
    Serial.println("IP address: ");
    Serial.println(WiFi.localIP());
 
    // Enable buffering.
    shell.enableBuffering( printBuffer, printBufferSize );
 
    // Enable password protection.
    shell.setPassword( passwordHash, sizeof( passwordHash ) );
 
    // initialize shell object.
    shell.begin( "arnold" );
 
    // Attach connect and disconnect callbacks.
    tcp.attachConnectCallback( userConnectedCallback );
    tcp.attachDisconnectCallback( userDisconnectedCallback );
 
    tcp.attachDebugChannel( &Serial );
    tcp.begin();
 
}
 
// Infinite loop.
void loop(){
 
    tcp.update();
    shell.update();
 
    // Give some time to the other tasks on RTOS systems.
    delay( 2 );
 
}
 
void userConnectedCallback( ShellminatorTcpSocket* socket ){
    // Print 'welcome' screen after connection.
    shell.printLoginScreen();
}
 
void userDisconnectedCallback( ShellminatorTcpSocket* socket ){
    // In case of disconnect event, close the terminal.
    shell.logOut();
}

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BLE Simple Example	WebSocket Self Hosted Example