EE 476: Homework 1

  1. Read all of Lab 1. You should come to lab with a good first draft of the code assignment, but the code is not part of this homework.
  2. List all jumpers which should be installed for the first lab assignment and describe why you need each one. Assume that the mcu operates at Vcc=5 volts.
  3. Estimate the Thevinin equvalent output resistance of an i/o pin from the Mega32 data sheet. There will be two separate estimates corresponding to whether the output is logic-high or logic-low.
  4. Assuming that an LED has a turn-on voltage of about 1.5 volts, and draws about 20 millamps, how many LEDs can you operate from the i/o ports before exceeding the chip rating.
  5. Produce a state-transition diagram for the Lab 1 reaction time tester, based on the diagram given in class. Be sure to consider what will happen if the slow human holds down a button for too long.
  6. Describe how you will implement the random number generator required in lab 1 to make a variable waiting time.

Jan 2004