ECE 270 Lab Verification / Evaluation Form Experiment 3 Evaluation: IMPORTANT! You must complete this experiment during your scheduled lab period. All work for this experiment must be demonstrated to and verified by your lab instructor before the end of your scheduled lab period. STEP DESCRIPTION MAX SCORE Pre-Lab 1 Function Representation 3 Pre-Lab 2 Schematic 5 1 Circuit Construction and Verification 6 2 Propagation Delay Measurements 3 3 Floating Input Investigation 3 4 Thought Questions 5 TOTAL 25 Signature of Evaluator: ________________________________________________________ Academic Honesty Statement: IMPORTANT! Please carefully read and sign the Academic Honesty Statement, below. You will not receive credit for this lab experiment unless this statement is signed in the presence of your lab instructor. Implementation of Dual and Complement Functions Instructional Objectives: • To learn how to implement simple logic functions using discrete 74HC-series components • To review the difference between the dual of a function and the complement of a function • To review how to measure logic signal propagation delays using the MSO Prelab Preparation: “In signing this statement, I hereby certify that the work on this experiment is my own and that I have not copied the work of any other student (past or present) while completing this experiment. I understand that if I fail to honor this agreement, I will receive a score of ZERO for this experiment and be subject to possible disciplinary action.” Printed Name: _____________________ Class No. __ __ __ __ - __ Signature: ____________________________________ Date: _______ECE 270 - Experiment 3 Purdue IM:PACT Little Bits Lab Manual © 2013 by D. G. Meyer Implementation of Dual and Complement Functions Instructional Objectives: • To learn how to implement simple logic functions using discrete 74HC-series components • To review the difference between the dual of a function and the complement of a function • To review how to measure logic signal propagation delays using the digital oscilloscope Pre-lab Preparation: • Read this document in its entirety • Complete the Pre-lab Steps Lecture/Demonstration: Your lab instructor will give a brief presentation that includes the following: • A review of dual and complement functions, illustrated using a complete example similar to the one that will be completed for lab • A demonstration of the completed experiment Experiment Description: Using only a 74HC00 (quad 2-input NAND, designated “U1”), a 74HC02 (quad 2-input NOR, designated “U2”), a 74HC04 (hex INVERTER, designated “U3”), and a 74HC10 (triple 3-input NAND, designated “U4”), realize the following three functions (simultaneously): (1) F(X,Y,Z) = X•(Y′+ Z) + X′•Y (2) FD(X,Y,Z) the DUAL of function F, above (3) F′(X,Y,Z) the COMPLEMENT of function F, above Use mini DIP-switches for inputs and RED (resistor) LEDs for outputs. Pre-lab Step (1): Function Representation Fill out the truth table, below, for the three functions you are to implement in this lab experiment. Show how you derived the truth table for each function. Have a written copy of your derivatory work available for your lab instructor to check. X Y Z F(X,Y,Z) FD(X,Y,Z) F′(X,Y,Z) 0 0 0 0 0 1 0 1 0 0 1 1 1 0 0 1 0 1 1 1 0 1 1 1ECE 270 - Experiment 3 Purdue IM:PACT Little Bits Lab Manual © 2013 by D. G. Meyer Pre-lab Step (2): Schematic Draw a complete schematic for your circuit using OrCAD Capture. Be sure to label all inputs and outputs, and include the DIP switches, pull-up SIP resistor, and LEDs. Print a copy of your schematic and have it available for your lab instructor to check. Note: Hand-written schematics will not be accepted. Step (1): Circuit Construction and Verification After constructing your circuit, fill out the truth table, below, to verify its operation (i.e., provide your circuit with each possible input combination and note the three function outputs). After completing the truth table below, compare it to the truth table you completed for Pre-lab (1). If there are discrepancies, you will need to “debug” your circuit/design! Have your lab instructor verify the functionality of your circuit. X Y Z F(X,Y,Z) FD(X,Y,Z) F′(X,Y,Z) 0 0 0 0 0 1 0 1 0 0 1 1 1 0 0 1 0 1 1 1 0 1 1 1 Step (2): Propagation Delay Measurements For each of the three functions, measure the rise and fall propagation delay (i.e., tPLH and tPHL). This can be done by connecting the oscillator module and frequency divider circuit (constructed for Experiment 2) to one of the function inputs while supplying a fixed combination (using DIP switches) to the other two inputs. NOTE: Choose a combination that will cause the function output to change state in response to the periodic input change provided by the 10 MHz frequency divider output – note that a different combination may be needed for each function. Delay F(X,Y,Z) FD(X,Y,Z) F′(X,Y,Z) tPLH tPHL Step (3): Floating Input Investigation Disconnect the function input connected to the oscillator output (used in Step (2), above) and allow the disconnected function input to “float” (i.e., do not reconnect it to the DIP switch). Also, disconnect the power supply from the oscillator module. Observe what happens as you touch and then release the end of the wire. Record your observations in the space below. ______________________________________________________________________________ ______________________________________________________________________________ECE 270 - Experiment 3 Purdue IM:PACT Little Bits Lab Manual © 2013 by D. G. Meyer Step (4) Thought Questions Place your answers to the following “thought questions” in the space provided below: (a) Which function was the “fastest”? Does this agree with your intuition based on how you realized that function? ___________________________________________________________________________ ___________________________________________________________________________ (b) Which function was the “slowest”? Does this agree with your intuition based on how you realized that function?