Thomson TG585 - button on front?

[#1]

I have the above router and have just enabled wirelss connection in preparation for a visitor who will be bringing his own laptop. I cannot tell yet if the wireless  is working as I don't have any wireless devices. On the front of the router there is a button with a wireless symbol (it may also illuminate - cannot tell) . What is the function of this button? I cannot see any reference to it in the setup literature provided.
Thanks

[#2]

Is it a Plusnet supplied Thomson TG585?  If so the button doesn't do anything.  v8 of the firmware uses it, possible to enable/disable the wireless, but v7 which is the current Plusnet supplied version doesn't.  Aparantly v8 is still quite a buggy firmware, though I don't have any experience of using it.
Phil

[#3]

Thanks for the speedy reply Phil. Yes - I do have the Plusnet supplied V7.

[#4]

The button is supposed to be used for connecting a wireless client via WPS (WiFi Protected Setup) - see page 22 of the manual.
I haven't tried this as it requires the client to also support WPS.

[#5]

Thanks for that Paul, and sorry for my mis-information! 
Phil

[#6]

No worries Phil!  I only knew because I got one of these routers for my mother-in-law and hunted down the manual as the one sheet of info supplied by PN only has basic connection details on it!!  (Wanted to know more about it as it'll be me who gets the phone calls when things aren't working )

[#7]

Paul - Thanks for the link to the manual.
Phil - no problem; the button is still redundant for me.
Gerry