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. Refering to the protoboard design page (and, of course, the Mega32 datasheet), describe the function of each of the components connected to pins 9, 10, 30,31,32 of the MCU.
  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. Look up the specifications (foward voltage and current) for a typical LED. Use these specifications to justify the choice of 300 ohms for the resistor on the lower right side of the protoboard design (revision 2).
  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.

Nov 2004