Page 122 - Making PIC Microcontroller Instruments and Controllers

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Exercises for Timers

l. Write a Fogram to genemte a l-minute time/clock with a 0 1 second display
Check its accuracy with the time site on the Intemet
Make adjustments so it is accurate to within 1 second per how' and then I second
per day. Can this be done? wlty? Which timer works best? which timer is the easiest
to use for such a task?
2. Wnte the preceding prcgmm for each of the other two timers.

Exercises for Counters

I. Desigl anal make a tachometer for smallmodel airqaft engines Have a ftnge of liom
5 rcv per second to 50 POO rer per minute displayed on the LCD in real-time
2, Design and build a thermometer based on the changes in frequency exhibjted by a
555 timer circuit behg controlled by a themistor. Calibmte the thermometer with a
lookup table. If you arc not familiar with the use of lookup tables, you should under-
take the research necessary to understand how to use them. They are very useful
devices at the level we arc working.