EE 308
Homework #11
Due April 11, 2000

  1. What register is the Sequence Complete Flag (SCF) in? How does the SCF flag get set? How do you clear it?

  2. Write some code which will enable the A/D converter, put it into 8-bit mode, and convert the analog inputs on pins PAD0 through PAD7 continuously.

  3. Write some code which will enable the A/D converter, put it into 10-bit mode, and convert the analog inputs on pins PAD0 through PAD7 once. Add some code which will wait until the eight conversions are completed.

  4. Write some code which will enable the A/D converter, put it into 8-bit mode, and convert the analog input on pin PAD3 eight times, then stop. Add some code which will wait until the eight conversions are completed.

  5. Add some code to the above problem which will average the eight values of the conversions of PAD3.

  6. On an HC12, VRL is connected to 1 V, and VRH is connected to 3 V. The A/D converter is set up to do 10-bit conversions.

    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 0x17B, what was the input voltage to the A/D converter?

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