mbed-os-example-wifi

WiFi example for mbed OS

Getting started with the WiFi API

This is a quick example of a simple WiFi application using the WiFi and network-socket APIs that is provided as a part of mbed-os.

The program brings up the WiFi and the underlying network interface, and uses it to scans available networks, connects to a network, prints interface and connection details and performs simple HTTP operation.

Supported hardware

• UBLOX Odin board built-in WiFi module
• REALTEK_RTL8195AM built-in WiFi module
• NUCLEO_F401RE with X-NUCLEO-IDW01M1 WiFi expansion board using pins D8 D2
• NUCLEO_F429ZI with ESP8266-01 module using pins D1 D0
• NUCLEO_L476RG with ESP8266-01 module using pins D8 D2
• Other mbed targets with ESP8266 module or X-NUCLEO-IDW01M1 expansion board (the mbed target board the WiFi shield gets connected to shouldn't have any other network interface e.g. Ethernet)

ESP8266 is a fallback option and will be used if the build is for unsupported platform.

Connecting the ESP8266

To connect the ESP8266 module to your development board, look at the ESP8266 Cookbook page. In general, this means hooking up the ESP8266 TX pin to D0 and the ESP8266 RX pin to D1 on your development board.

Note: on NUCLEO development boards, pins D0 and D1 are used for serial communication with the computer. Use pins D8 (to ESP8266 TX) and D2 (to ESP8266 RX) instead.

Connecting the X-NUCLEO-IDW01M1

To connect the X-NUCLEO-IDW01M1 expansion board to your NUCLEO development board, just plug the expansion board on top of the NUCLEO board using the Morpho connector.

Getting started

1. Import the example

   mbed import mbed-os-example-wifi
   cd mbed-os-example-wifi
   

2. Configure the WiFi shield to use

   Edit mbed_app.json to include correct WiFi shield, SSID and Password:

       "config": {
      "wifi-shield": {
               "help": "Options are WIFI_ESP8266, WIFI_IDW01M1",
               "value": "WIFI_IDW01M1"
        	  },
           "wifi-ssid": {
               "help": "WiFi SSID",
               "value": "\"SSID\""
           },
           "wifi-password": {
               "help": "WiFi Password",
               "value": "\"Password\""
           }
       },
   

   For built-in WiFi, ignore the value of wifi-shield

3. Copy the respective ignore file to .mbedignore

   • Copy esp8266-mbedignore when using ESP8266 module.
   • Copy idw01m1-mbedignore when using X-NUCLEO-IDW01M1 expansion board.
   • For built-in WiFi, keep the default .mbedignore

4. Compile and generate binary

   For example, for GCC:

   mbed compile -t GCC_ARM -m UBLOX_EVK_ODIN_W2
   

5. Open a serial console session with the target platform using the following parameters:

   • Baud rate: 9600
   • Data bits: 8
   • Stop bits: 1
   • Parity: None

6. Copy or drag the application mbed-os-example-wifi.bin in the folder mbed-os-example-wifi/BUILD/<TARGET NAME>/<PLATFORM NAME> onto the target board.

7. The serial console should display a similar output to below, indicating a successful WiFi connection:

WiFi example

Scan:
Network: Dave Hot Spot secured: Unknown BSSID: 00:01:02:03:04:05 RSSI: -58 Ch: 1
1 network available.

Connecting...
Success

MAC: 00:01:02:03:04:05
IP: 192.168.0.5
Netmask: 255.255.255.0
Gateway: 192.168.0.1
RSSI: -27

Sending HTTP request to www.arm.com...
sent 38 [GET / HTTP/1.1]
recv 64 [HTTP/1.1 301 Moved Permanently]

Done

Documentation

More information on the network-socket API can be found in the mbed handbook.