An installation comprises at least one sensor for providing sensor data representing a real system state of the installation and at least one actuator for acting on the real system state. A controller for controlling the installation comprises a data memory for storing the sensor data and a program memory for storing a machine code program. A programming tool for programming the controller includes a program editor, a debugging tool and a compiler. A machine code program is executed on the controller while the debugging tool is activated, and the debugging tool determines a reverse relationship between the machine code running on the controller and at least one high level control instruction shown in the program editor, thereby linking at least one high level control instruction to a real system state during the execution of the machine code program.