Whatever device it is isn't configured to act as a DHCP server or running NAT, so it may have a statically assigned IP, or may be using an automatic IP assignment the way Windows does, but who knows what IP range it might default to. Find out whether the PSP does such a thing and pick a random IP from that range and you might be able to connect.
Is it actually hurting anything or is it violating a rule, or are you just curious?