mbed-os-example-wifi

Wi-Fi example for Mbed OS

Getting started with the Wi-Fi API

This is an example of a Wi-Fi application using the Wi-Fi and network socket APIs that Mbed OS provides.

The program brings up the Wi-Fi and the underlying network interface and uses it to scan available networks, connects to a network, prints interface and connection details and performs an HTTP operation.

For more information about Wi-Fi APIs, please visit the Mbed OS Wi-Fi documentation.

Supported hardware

• u-blox Odin board built-in Wi-Fi module.
• Realtek RTL8195AM built-in Wi-Fi module.
• NUCLEO-F401RE with X-NUCLEO-IDW04A1 Wi-Fi expansion board using pins D8 and D2 (of the Arduino connector).
• NUCLEO-F401RE with X-NUCLEO-IDW01M1 Wi-Fi expansion board using pins PA_9 and PA_10 (of the Morpho connector).
• NUCLEO-F429ZI with ESP8266-01 module using pins D1 and D0.
• NUCLEO-L476RG with ESP8266-01 module using pins D8 and D2.
• Other Mbed targets with an ESP8266 module, X-NUCLEO-IDW04A1 or X-NUCLEO-IDW01M1 expansion board. (The Mbed target board the Wi-Fi shield connects to shouldn't have any other network interface, for example Ethernet.)

ESP8266 is a fallback option 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-IDW0XX1

To connect the X-NUCLEO-IDW04A1 or X-NUCLEO-IDW01M1 expansion board to your NUCLEO development board, plug the expansion board on top of the NUCLEO board using the Arduino or Morpho connector.

Getting started

1. Import the example.

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

2. Configure the Wi-Fi shield to use.

   Edit mbed_app.json to include the correct Wi-Fi shield, SSID and password:

       "config": {
      "wifi-shield": {
               "help": "Options are WIFI_ESP8266, WIFI_IDW0XX1",
               "value": "WIFI_ESP8266"
        	  },
           "wifi-ssid": {
               "help": "WiFi SSID",
               "value": "\"SSID\""
           },
           "wifi-password": {
               "help": "WiFi Password",
               "value": "\"Password\""
           }
       },
   

   Sample mbed_app.json files are provided for ESP8266 (mbed_app_esp8266.json), X-NUCLEO-IDW04A1 (mbed_app_idw04a1.json) and X-NUCLEO-IDW01M1 (mbed_app_idw01m1).

   For built-in Wi-Fi, ignore the value of wifi-shield.

3. Compile and generate binary.

   For example, for GCC:

   mbed compile -t GCC_ARM -m UBLOX_EVK_ODIN_W2
   

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

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

5. 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.

6. The serial console should display a similar output to below, indicating a successful Wi-Fi 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

Troubleshooting

If you have problems, you can review the documentation for suggestions on what could be wrong and how to fix it.