First you need to get in the ap boot, and you do it by connecting it through console when you boot up the ap you start pressing any key for example enter and you press it untill you see apboot>
Here is the list of Commands are their meaning:
setenv ipaddr 172.16.3.223
This Comand will set the static ip address to AP
setenv netmask 255.255.255.0
This command will set the subnet mask to the AP
setenv gatewayip 172.16.3.1
This command will set the ip default gateway to the AP
setenv serverip 172.20.5.25
This command will set from which controller he will download the new image
setenv master 172.20.5.25
This command will tell the ip which is the master controller
setenv group raphome
This command will tell the ip which group he belongs
setenv name Carlos_AP
This command will tell the IP his name
saveenv
This command will save the configuration
dhcp
This command will help you to know if you are reciving DHCP addresses
purgeenv
This command will delete all the variables you configured on the apboot
clearos
This command will delete the Firmware you downloaded from the controller and will put the ap OS that came from the fabric i mean from aruba when you first turned it on
factory_default
This command will totally factory default the AP