Serial Mouse
A 2 or 3 button serial mouse could be connected via a little adapter cable to the QL's serial port, and software by Albin Hessler (called SerMouse) was used to ensure it looked like a QIMI mouse to the system. The software needed configuring to the type of mouse used, and some types of mouse required that the left hand mouse button be held down as the QL switched on, so that the mouse was set to the required mode.