A method of communicating with a well logging tool disposed in a well bore comprising: (a) running a drill pipe string having a longitudinal bore into a well bore to a predetermined position, said drill pipe string including a landing sub disposed proximal to a lower end of the drill pipe string,; (b) disposing in the longitudinal bore of the drill pipe string a logging tool string comprising a landing assembly, at least one logging tool,; (c) landing the landing assembly of the logging tool string in the landing sub of the drill pipe string wherein at least a portion of the logging tool string including the at least one logging tool is disposed below a distal end of the drill pipe string and at least a portion of the logging tool string is contacting a well bore wall; the method characterised in that said landing sub includes a landing sleeve having at least one magnet disposed in the landing sleeve and the logging tool string includes a sensing device comprising a switch adapted to be activated when the switch in the logging tool string is proximal to the magnet in the landing sleeve and which is activated when the landing assembly is landed in the landing sub and the method includes: (d) sending a signal to a processor in the logging tool string when the switch is activated; (e) raising the drill pipe string while the logging tool string is stationary and contacting the well bore wall, thereby moving the landing sleeve with the magnet relative to the switch disposed in the logging tool string and de-activating the switch; (f) sending a signal to the processor in the logging tool string when the switch is de- activated after being moved away from the magnet; (g) lowering the drill pipe string and positioning the switch in proximity to the magnet thereby re-activating the switch and sending a signal to the processor; (h) repeating the raising and lowering of the drill pipe string one or more times in a predetermined time sequence thereby sending a signature signal to the processor; and (i) in the processor, matching the signature signal received by the processor to a signature signal pattern stored in the processor and sending an output signal correlating to the stored signature pattern to the at least one logging tool to perform an operation. (a) running a drill pipe string having a longitudinal bore into a well bore to a predetermined position, said drill pipe string including a landing sub disposed proximal to a lower end of the drill pipe string,; (b) disposing in the longitudinal bore of the drill pipe string a logging tool string comprising a landing assembly, at least one logging tool,; (c) landing the landing assembly of the logging tool string in the landing sub of the drill pipe string wherein at least a portion of the logging tool string including the at least one logging tool is disposed below a distal end of the drill pipe string and at least a portion of the logging tool string is contacting a well bore wall; the method characterised in that said landing sub includes a landing sleeve having at least one magnet disposed in the landing sleeve and the logging tool string includes a sensing device comprising a switch adapted to be activated when the switch in the logging tool string is proximal to the magnet in the landing sleeve and which is activated when the landing assembly is landed in the landing sub and the method includes: (d) sending a signal to a processor in the logging tool string when the switch is activated; (e) raising the drill pipe string while the logging tool string is stationary and contacting the well bore wall, thereby moving the landing sleeve with the magnet relative to the switch disposed in the logging tool string and de-activating the switch; (f) sending a signal to the processor in the logging tool string when the switch is de- activated after being moved away from the magnet; (g) lowering the drill pipe string and positioning the switch in proximity to the magnet thereby re-activating the switch and sending a signal to the processor; (h) repeating the raising and lowering of the drill pipe string one or more times in a predetermined time sequence thereby sending a signature signal to the processor; and (i) in the processor, matching the signature signal received by the processor to a signature signal pattern stored in the processor and sending an output signal correlating to the stored signature pattern to the at least one logging tool to perform an operation.