The phyCORE-AM65x SOM comes equipped with a WifFi module. This guide shows you how to connect and use this interface.

The phyCORE-AM65x cannot boot from an SD card and utilize the WiFi module at the same time as they share the same bus. This guide assumes that you are booting from eMMC. See Flashing and Booting From eMMC and Boot Switch Configuration for more info on booting from eMMC.

Step-by-step guide

Set up Software Configuration

In order to be accessible in Linux, the WIFI module needs to be configured in the Linux device tree. PHYTEC has provided a sample device tree overlay which configures the MMC bus to utilize the WiFi module instead of the SD Card slot at X13. To enable this device tree overlay:

  • The device tree overlay is set in U-Boot. 

  • To enter U-Boot, hit any key within 3 seconds of powering or resetting the board to exit autoboot.

    • If the board is powered on to begin with you will need to reset the board by pushing the Cold Reset button (S1) or use the following command to power off: 

      Target (Linux)
      poweroff
  • Modify the "extra_overlays" variable to point to the sample dtbo: "k3-am65xx-phytec-wlan.dtbo". The "default_overlays" variable does not need to be changed.

    Target (U-Boot)
    setenv extra_overlays k3-am65xx-phytec-wlan.dtbo
    saveenv
  • Now boot into Linux using the following command in U-Boot: 

    Target (U-Boot)
    boot

Configure WiFi

  • A 'wpa_supplicant' file must contain the necessary credentials to connect to your network.

    Target (Linux)
    vi /etc/wpa_supplicant.conf
  • Ensure that this file reflects the following contents (replace NETWORKNAME and NETWORKPASSWORD to the corresponding credentials for your target network): 

    vi Text Editor
    ctrl_interface=/var/run/wpa_supplicant
    ctrl_interface_group=0
    update_config=1
    
    network={
            ssid="NETWORKNAME"
            key_mgmt=WPA-PSK
            psk="NETWORKPASSWORD"
    }

    The vi text editor begins in "Command Mode" and you must first hit the 'i' key in order to enter "Insert Mode". Using the arrow keys to navigate, make the necessary changes and then hit ESC to go back to "Command mode". Now enter ":wq" to write the file and quit.

Establish the Connection

  • Load the credentials from the previous step:

    Target (Linux)
    wpa_supplicant -B -i wlan0 -c /etc/wpa_supplicant.conf
  • Launch the WiFi client 

    Target (Linux)
    udhcpc -i wlan0
  • Wait until you obtain an IP address.
  • Test your connection 

    Target (Linux)
    ping google.com

    Expected Output
    root@am65xx-phycore-kit:~# ping google.com
    PING google.com (172.217.14.206): 56 data bytes
    64 bytes from 172.217.14.206: seq=0 ttl=53 time=15.934 ms
    64 bytes from 172.217.14.206: seq=1 ttl=53 time=16.603 ms
    64 bytes from 172.217.14.206: seq=2 ttl=53 time=15.380 ms
    64 bytes from 172.217.14.206: seq=3 ttl=53 time=13.408 ms
  • Enter Ctrl + C to stop pinging.

Revert to the Default Software Configuration

This guide required enabling a device tree overlay that disabled use of the SD Card slot at X13. In order to revert back to the default overlay settings, the following needs to be run in U-Boot:

  • To enter U-Boot, hit any key within 3 seconds of powering or resetting the board to exit autoboot.
  • To revert back to the original device tree (which would again disable WiFi), enter the following command in U-Boot: 

    Target (U-Boot)
    env default -f -a
    saveenv
  • Now use this command to boot into Linux with the original device tree enabled (no WiFi): 

    Target (U-Boot)
    boot