Design an elevator controller for a two floor elevator. The inputs FB1 and FB2 are 1 when someone in the elevator presses the first or second floor buttons, respectively. The inputs call1 and call2 are 1 when someone on the first or second floor presses the elevator call button. The inputs FS1 and FS2 are 1 when the elevator is at the first or second floor landing. The output UP turns on the motor to raise the elevator car; DOWN turns on the motor to lower the elevator. If neither UP or DOWN is 1, then the elevator will not move. R1 and R2 reset latches; and when DO goes to 1, the elevator door opens. After the door opens and remains open for a reasonable length of time, the door controller mechanism closes the door and sets DC =1. Assume that all input signals are properly synchronized with the system clock.