Abstract: An apparatus for generating function signals to an elevator controller for controlling an elevator car (1) at terminal landings in a building includes an upper cam (3) and a lower cam (4) for mounting on a wall (2a, 2b) in an elevator shaft (2) at a top landing and a bottom landing respectively, an upper switch (5) and a lower switch (8) for mounting on the elevator car and for connection to a source of electrical power (12) and an interface circuit (10) connected to the switches. The interface circuit (10) has a lower limit relay coil (16), an upper limit relay coil (27), normally closed up relay contact sets (17,19,35) and normally closed down relay contact sets (24,28,30) which cooperate with the switches (5,8) for generating upper and lower limit function signals to control car travel and upper and lower slow down signals to control car speed.