I am helping a student with his assignment. 80C517A Microcontroller. U-Vision Keil compiler and d-scope debugger. The first task is to simulate a microcontroller based "egg timer" with which the user inputs the required time in seconds (range 0 to 99) via an input port by simulating a two pin shaft encoder. The time is then displayed using the serial window. The second task is to implement the program on the target hardware. In this case the time should be displayed using the hex display board JK6. These tasks are to make use of the on board timer and interrupt facility of the microcontroller. If anyone can help with the following questions, it would be greatly appreciated as the student needs to understand this before Monday 14th May 2001. Thanks. Andrew Pearse ABPC Ltd +44 1845 524222 Questions Q1. What is a two pin shaft encoder and how could it be simulated with U-vision? (ie what port would it connect to and what addresses would need to be read by the C program?) Q2. Can the interrupt facility of the microcontroller be simulated and how, using a C program? Q3. How can the on-board timer of the microcontroller be set-up and used, with a C program? Q4. Is there any information about the JK6 hex display board? How does it connect to the microcontroller? How does the C program set the display values of the JK5? END OF MESSAGE