sinclair spectrum?

as some people might remember a few months ago, a screenie from a version of doom on the sinclair spectrum appeared on the POTD of doomworld. i was just wondering, is it possible to get this "port" (best word i can think of) anywhere?

actually, i found it, but now i have a different question relating to it. i can move forward and backward, shoot, change weapons and get up the map. does anyone know how to do other stuff? (turn left and right, etc.)

UPDATE: I've worked out how to turn. I might upload some screenies soon of it.