TIMERS AND COUNTERS:Exercises for Timers and Exercises for Counters

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Exercises for Timers

1. Write a program to generate a one minute timer clock with a 0.1 second display and then do the following:

N Check its accuracy with the time site on the Internet.

N Make adjustments to make it accurate to within one second per hour and then per day. Can this be done? Which timer works best? Which timer is the easiest to use for such a task? What are the problems that you identified?

2. Write the preceding program for each of the other two timers.

Exercises for Counters

1. Design and make a tachometer for small model aircraft engines. Make the range

between 5 rev per second to 50,000 rev per minute displayed on the LCD in real time.

2. Design and build a thermometer based on the changes in frequency exhibited by a 555 timer circuit being controlled by a thermistor. Calibrate the thermometer with a lookup table. If you are not familiar with the use of lookup tables, research on the Internet so you can understand how to use them. They are very useful devices at the level that we are working.

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