Question:
Write a Verilog description for the state-machine diagram for the batch mixing system derived in Example 11.
Data From Example 11.
Transcribed Image Text:
EXAMPLE 11 State-Machine Design of a Sliding Door Control Automatic sliding entrance doors are widely used in retail stores. In this example, we consider the design of the sequential logic for controlling a sliding door. The one-way door opens in response to three sensors PA (Approach Sensor), PP (Presence Sensor), DR (Door Resistance Sensor), and to a pushbutton MO (Man- ual Open). PA senses a person or object approaching the door, and PP senses the presence of a person or object within the doorframe. DR senses a resistance to the door closing that is at least 15 pounds indicating that the door is pushing on a person or obstacle. MO is a manual pushbutton on the door control box that opens the door without dependence on the automatic control. The door control box also has a keyed lock LK for locking the door closed using an electrically- operated bolt BT to prevent entrance when the store is closed. In addition to these inputs to the door logic, there are two limit switches CL (close limit) and OL (open limit) that determine when the door mechanism has closed the door completely or opened the door completely, respectively. The control mechanism has just three outputs, BT (bolt), CD (close door) and OD (open door). All of the inputs or outputs are described along with the meaning of value 1 and value 0 for each of them in Table 11.