Hi Rod,
DietPi disables all known WiFi modules by default. This is to reduce memory usage.
To enable the WiFi adpater, either:
- use dietpi-config > Networking to setup the adapter
- Enable the WiFi modules and then setup manually:
/DietPi/dietpi/func/dietpi-set_hardware wifi onboard_enable
/DietPi/dietpi/func/dietpi-set_hardware wifi enable