EE 308
Homework #10
Due April 17, 1998

1. How does the CCF flag get set? How do you clear it?

2. Write some code which will make the HC11 A/D converter convert the analog inputs on pins PE4 through PE7 continuously.

3. Write some code which will make the HC11 A/D converter convert the analog inputs on pins PE0 through PE3 once. Add some code which will wait until the four conversions are completed.

4. Write some code which will make the HC11 A/D converter convert the analog input on pin PE3 four times, then stop. Add some code which will wait until the four conversions are completed.

5. Add some code to the above problem which will average the four values of the conversions of PE3.

6. On an HC11, VRL is connected to 1 V, and VRH is connected to 3 V.

   1. What voltage step will cause the A/D converter to change value?

   2. If the input to the A/D converter is 2.3 V, what number will result from a conversion?

   3. If the result of a conversion is 0x27, what was the input voltage to the A/D converter?

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Bill Rison, <rison@ee.nmt.edu >