Category Archives: ESP32 MongooseOS

ESP32 Mongoose OS Interface -MQTT

Mongoose OS Credentials configure

Two way to configure the MQTT Credentials in Mongoose OS file. This Example tested with mongoose os , demo-js app, windows 10, 64bit, mos tool, ESP32 DevKitC from ESPressif.

First one is using mos tool UI
- GO to 127.0.0.1:1992/ –> Device Config –> Change the MQTT Credential in MQTT Setting and Save with Reboot
- Afterwards its generate the new file name is conf9.json
Second methods is change the mqtt Credential in conf0.json file

Required

ESP32 Any kind of boards
Mongoose OS firmware
Mos Tool
MQTT Server Credentials
WiFi Crendentials

Note : This ESP32 Mongoose OS interface – MQTT is tested with Windows 10 64bit machine, mos tool(Web Browser based IDE for Mongoose OS), ESp32 DevkitC board from ESPressif.

Follow

Make sure already set your WiFi Credentials (otherwise MQTT is not work, also check the MQTT Connected status in Terminal windows)

Code : init.js file

load('api_config.js');
load('api_events.js');
load('api_gpio.js');
load('api_mqtt.js');
load('api_sys.js');

let button = Cfg.get('pins.button');
let topic = '/devices/' + Cfg.get('device.id') + '/events';

print('button GPIO:', button);

let getInfo = function() {
  return JSON.stringify({
    total_ram: Sys.total_ram(),
    free_ram: Sys.free_ram()
  });
};

// Publish to MQTT topic on a button press. Button is wired to GPIO pin 0
GPIO.set_button_handler(button, GPIO.PULL_UP, GPIO.INT_EDGE_NEG, 20, function() {
  let message = getInfo();
  let ok = MQTT.pub(topic, message, 1);
  print('Published:', ok, topic, '->', message);
}, null);

// Monitor network connectivity.
Event.addGroupHandler(Net.EVENT_GRP, function(ev, evdata, arg) {
  let evs = '???';
  if (ev === Net.STATUS_DISCONNECTED) {
    evs = 'DISCONNECTED';
  } else if (ev === Net.STATUS_CONNECTING) {
    evs = 'CONNECTING';
  } else if (ev === Net.STATUS_CONNECTED) {
    evs = 'CONNECTED';
  } else if (ev === Net.STATUS_GOT_IP) {
    evs = 'GOT_IP';
  }
  print('== Net event:', ev, evs);
}, null);

Output

Results : {“free_ram”:148676,”total_ram”:229296}
Topic : /device/esp32_0255EC/events

Hits (since 2024-Jan-26) - 330

ESP32 Mongoose-OS Interface – WiFi

WiFi Status Monitor

// Monitor network connectivity.
Net.setStatusEventHandler(function(ev, arg) {
  let evs = "???";
  if (ev === Net.STATUS_DISCONNECTED) {
    evs = "DISCONNECTED";
  } else if (ev === Net.STATUS_CONNECTING) {
    evs = "CONNECTING";
  } else if (ev === Net.STATUS_CONNECTED) {
    evs = "CONNECTED";
  } else if (ev === Net.STATUS_GOT_IP) {
    evs = "GOT_IP";
  }
  print("== Net event:", ev, evs);
}, null);

Hits (since 2024-Jan-26) - 351

ESP32 Mongoose OS – Basic Examples

This article is about ESP32 Mongoose OS – Basic Examples, Let’s go through a basic example of using UART (Universal Asynchronous Receiver-Transmitter), Button and blinking an LED using an ESP32 by Mongoose OS.

Mongoose OS is an open-source IoT operating system designed for low-power, connected microcontrollers. Below is a basic example to get you started with Mongoose OS on an ESP32. This example demonstrates how to create a simple firmware that blinks an LED.

This is a basic example to help you get started with Mongoose OS on an ESP32. It blinks an LED using the GPIO capabilities provided by Mongoose OS. From here, you can explore additional features and libraries provided by Mongoose OS to build more sophisticated IoT applications. Refer to the Mongoose OS documentation for detailed information and advanced usage.

Setup Required

PC
UART Terminal (Putty, Visual Studio Serial Terminal, DockLight)
LEDs

UART Serial

Print words, string, text, symbols

print('------------****************----------------');
print('ArunEworld');

ESP32 Mongoose OS – Basic Examples of UART Communication

// https://github.com/cesanta/mongoose-os/blob/master/fw/examples/mjs_uart/init.js
// Load Mongoose OS API
load('api_timer.js');
load('api_uart.js');
load('api_sys.js');

// Uart number used for this example
let uartNo = 1;
// Accumulated Rx data, will be echoed back to Tx
let rxAcc = "";

let value = false;

// Configure UART at 115200 baud
UART.setConfig(uartNo, {
  baudRate: 115200,
  esp32: {
    gpio: {
      rx: 16,
      tx: 17,
    },
  },
});

// Set dispatcher callback, it will be called whenver new Rx data or space in
// the Tx buffer becomes available
UART.setDispatcher(uartNo, function(uartNo, ud) {
  let ra = UART.readAvail(uartNo);
  if (ra > 0) {
    // Received new data: print it immediately to the console, and also
    // accumulate in the "rxAcc" variable which will be echoed back to UART later
    let data = UART.read(uartNo);
    print("Received UART data:", data);
    rxAcc += data;
  }
}, null);

// Enable Rx
UART.setRxEnabled(uartNo, true);

// Send UART data every second
Timer.set(1000 /* milliseconds */, true /* repeat */, function() {
  value = !value;
  UART.write(
    uartNo,
    "Hello UART! "
      + (value ? 'Tick' : 'Tock')
      + " uptime: " + JSON.stringify(Sys.uptime())
      + " RAM: " + JSON.stringify(Sys.free_ram())
      + (rxAcc.length > 0 ? (" Rx: " + rxAcc) : "")
      + "\n"
  );
  rxAcc = "";
}, null);

GPIO Module

View On GitHub : api_gpio.js