Cycle computer (Woodhouse Eaves LE12)

As per photo, I know nothing about it and have no manual, it came attached to a bike I bought.
It seems to be from a company called Cadence, and there's a number on the back, 302p, but I can't find any more.
There's a head unit, attached by cable to a pedal sensor, and there's also a speed monitor and magnet, which were on the front wheel but are not wired.
Anyone want to take this on?