CP316: Microprocessor Systems and Interfacing

Rotary Pulse Generator

Objectives

Shaft encoders are very common. The rotary pulse encoder uses a shaft encoder. In this lab you will:

• create a menu of at least 5 items
• display the menu on the LCD display
• scroll forward and back through the menu using the rotary pulse generator
• select an item with the pushbutton switch and indicate it on the LCD display

Equipment

• QwikFlash Development Board
• microcomputer with MPLAB IDE and MPLAB ICD2 installed
• Digital inputs: rotary pulse generator
  
• Digital inputs: pushbutton
  

Procedure

1. Create a menu of at least five items, and have them display consecutively with a reasonable time interval between.
   Demonstration - show menu items
   
   
2. Use the rotary pulse generator to move through he itmes, forward and backward. If necessary, divide the count so that the amount of rotation between items is reasonable.
   Demonstration - using the rotary pulse generator to move through items.
   
   
3. Now use the switch, (SW3 on the schematic), to select an item. Display the word "SELECTED" under an item when the switch is pressed. It should be that when the button is released, the item remains selected until a different item is selected. In other words, if you continue scrolling through the menu, that item will appear as selected each time it shows up until you select something else.
   Demonstration - persistent selection