Abstract: A display (22) has one or more digits (22-1, 22-2) each capable of displaying a plurality of alphanumeric characters. A character control (10) has an output line (12) for each possible character and provides a signal over the line to cause the character to be displayed by activating an opto-isolation device (20-1). The output lines (20-1) are connected to a plurality of scan devices (26-1) which are individually addressed by a computer (28). Each scan device (26-1) is connected to a group of lines (20-2) that are individually addressed by the computer (28). When a line (20-2,20-3) is found to have a signal on it, the line is given a name which is used by the computer (28) to read a stored code from a memory (28-2). This code is keyed to the display to cause the display to provide the character associated with the line name, hence, the line, and the code is then supplied serially to the display which displays the character when all the components of the code have been received.

Abstract: A computer-controlled system, such as an elevator, is tested by augmenting computer operation with a diagnostic device containing a computer and coded diagnostic programs that a service technician identifies through a keyboard using diagnostic test codes that appear on an overlay which contains special codes and identifiers associated with numerical displays and lights on the diagnostic device for correlating test results to the test performed according to the program.

Abstract: To control an elevator motor, a first analog signal, the profile of which defines the velocity characteristics during acceleration, is generated in response to a motor jerk signal, a signal to accelerate the motor. This first analog signal is then multiplied with a second analog signal to provide a third analog signal which is supplied to the motor controls. The magnitude and polarity of that third analog signal controls motor speed and direction. The second analog signal has a unity value, a value of one, except when the car is within a slowdown distance from the floor. When the car moves through that range, the second analog signal decreases from unity. The second analog signal is provided from digital coefficients that are stored in a memory device and addressable for particular positions from the slowdown position. The coefficients are addressed by the output from a down counter that counts pulses that are provided by a car position transducer as the car moves from the slowdown position.

Abstract: An elevator includes a microprocessor-based cab controller mounted on the elevator car to monitor calls for service by passengers in the car, controls the opening and closing of the door, monitors the position of the car relative to an adjacent landing and communicates with a microprocessor-based car controller, disposed at the top of the shaftway, which controls the motion of the car in the shaftway and provides commands to the cab controller, such as door opening and closing demands relating to calls at the landings, and the like. The cab controller monitors the viability of communications which it receives from the car controller, monitors the position of the door relative to the position of the car with respect to floor landings and provides a signal to enable applying power to the sheave-driving motor and the brake pick-up coils in the machine room only in the event that such monitoring indicates no safety problems.