WiFi Access Point

Configure the ESP32 as a WiFi access point (soft APAccess Point) that other devices can connect to. Logs connect/disconnect events and periodically lists connected clients. See the wifi APIApplication Programming Interface reference for the full type surface.

Hardware

• Any ESP32 board with WiFi
• USBUniversal Serial Bus cable
• A phone or laptop to connect to the APAccess Point

Code

import {sleep} from 'mikro/sleep'
import {wifi} from 'mikro/wifi'

// Start the access point
wifi.ap
  .start({
    ssid: 'MikroJS-AP',
    passphrase: 'hello1234',
    channel: 6,
    maxConnections: 4,
  })
  .orPanic('Failed to start access point')

console.log('Access point started')
console.log('SSID: MikroJS-AP')
console.log('IP: %s', wifi.ap.ip)

// Log when stations connect/disconnect
wifi.ap.onStationConnect.subscribe((info) => {
  console.log('Station connected: %s', info.mac)
})

wifi.ap.onStationDisconnect.subscribe((info) => {
  console.log('Station disconnected: %s', info.mac)
})

// Periodically print connected stations
while (true) {
  await sleep(10000)
  const stations = wifi.ap.stations
  if (stations.length > 0) {
    console.log(`Connected stations (${stations.length}):`)
    for (const sta of stations) {
      console.log(`  ${sta.mac} (RSSI: ${sta.rssi})`)
    }
  }
}

Walkthrough

1. Country code. wifi.country must be set before any WiFi operation. It determines which channels and power levels are legal in your region.

2. Access point config. wifi.ap.start() takes an SSIDService Set Identifier, passphrase (minimum 8 characters), channel number, and maximum client count. .orPanic() crashes with a clear message if startup fails.

3. Event streams. wifi.ap.onStationConnect is an Observable<ApStationInfo> that emits whenever a device joins the network. Subscribe with .subscribe(callback); the callback receives the client's MACMedia Access Control address. Disconnect works the same way via onStationDisconnect.

4. Connected clients. wifi.ap.stations returns an array of currently connected stations, each with a mac address and rssi signal strength. The example polls this every 10 seconds.

5. No internet needed. Unlike wifi.connect(), the access point does not require an existing network. Useful for device configuration portals, direct peer communication, or field deployments without infrastructure.

Create project

pnpm

pnpm create mikro --template wifi-access-point

npm

npm create mikro -- --template wifi-access-point

yarn

yarn create mikro --template wifi-access-point

bun

bun create mikro --template wifi-access-point

Run it

pnpm

pnpm install
pnpm mikro flash  # only needed once per board
pnpm mikro dev

npm

npm install
npx mikro flash  # only needed once per board
npx mikro dev

yarn

yarn install
yarn mikro flash  # only needed once per board
yarn mikro dev

bun

bun install
bunx mikro flash  # only needed once per board
bunx mikro dev

After deploying, look for the "MikroJS-APAccess Point" network on your phone or laptop. Connect with password hello1234. The console logs the connection.

View source on GitHub