ECET 105 Week 1 Homework

For more classes visit www.snaptutorial.com 1. Does a typical computer have any analog outputs? If so, what are they? 2. List three advantages of digital signal representation as compared to their analog representation. 3. Convert 126 x 10+2 to scientific and engineering notations. 4. Make the following conversions: a. Convert 0.34 seconds to milliseconds. b. Express 0.0005 x 10-4 farads as picofarads. 5. The frequency of a signal is equal to the reciprocal of the signal’s period (f = 1/p). For a computer with a 2.4 GHz clock, what is the clock period? Use engineering notation for your answer. 6. The signal shown below is a sine wave as it might be displayed on an oscilloscope. If it takes 40 msec. for the waveform to travel between the points shown by the arrow “B” below, what is the frequency of the waveform? 7. Power (in watts) is a certain amount of energy (in joules) divided by a certain length of time (in seconds). The laser with the highest peak power produces energy of 186 joules in 167 femtoseconds. What is the peak power? Use engineering notation for your answer. (Note: Use references to determine the value of a femtosecond and the proper notation for your answer.) 8. Which logic function produces a HIGH output only when all of the inputs are HIGH?

9. Which logic function produces a HIGH output only when all of the inputs are LOW? 10. Using the Internet, find the data sheet for the 74LS00 integrated circuit chip. Answer the following:

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ECET 105 Week 1 iLab Introduction to Laboratory Test Equipment

For more classes visit www.snaptutorial.com I. OBJECTIVES 1. To learn the function and basic operation of the instruments comprising a test bench 2. To gain a basic understanding of how to use the power supply, DMM, oscilloscope, and function generator 3. To take measurements using the power supply, DMM, oscilloscope, and function generator 4. To determine waveform characteristics of various signals II. PARTS LIST Equipment IBM PC or Compatible with Windows 2000 or Higher ELVIS II+ Parts 1 - 1.0 kohm Resistor (color bands = brown, black, red, gold)

1 - 4.7 kohm Resistor (color bands = yellow, violet, red, gold) III. PROCEDURES A. Introduction to Instruments and Measurements Before beginning this lab, be sure that you have read the Lab Prepfor an explanation of how to use the various instruments. 1. Measure DC voltage with the DMM. a. Attach the power supply +5 V outputs to the DMM inputs. b. Launch the ELVIS II+ DMM and select DC Voltage. 1. Press Run and record the reading below, including units. 2. Press Stop. DMM measurement ___________________________ 2. Measure DC voltage with the oscilloscope. 1. Launch the ELVIS II+ 2. Enable Channel 0. 3. Ensure the following settings. • Probe—10x • Coupling—DC • Scale—2 Volts/Div • Vertical Position—0 • Timebase—50 us/Div • Trigger Type—Immediate • Trigger Source—Chan 0 Source • Horizontal Position—50 • Acquisition Mode—Run Continuously 1. Connect the oscilloscope probe from the oscilloscope to the +5 V output (main probe to +5 V and ground to GND). 2. Press Run and read the voltage on the oscilloscope. Record your reading with the appropriate unit in engineering notation. Vertical scale _____________ Horizontal scale______________ V = _____________ 1. Press Stop. 3. Measure resistance with the DMM. 4. Remove a 1 kohm resistor (color bands are brown, black, red, gold) from the parts kit. The first three bands indicate the value of the

resistor and the fourth band indicates the accuracy of the resistance. A gold band indicates that the measured value should be within ±5% of the specified value. 5. Switch the DMM to ohms (Ω) and measure the resistor value by clipping the probes to each end of the resistor. 6. Press Start and record the measured value and the calculated range (1 kohm ±5%) including units. DMM measurement ____________________________ Theoretical range ______________________________ 7. Repeat Step 3 with the 4.7 kohm resistor (color bands are yellow, violet, red, and gold) including units. DMM measurement ____________________________ Theoretical range ______________________________ 8. Press Stop. 4. Measure a changing signal voltage with the oscilloscope. 9. Launch the ELVIS II+ frequency generator. 1. Connect the frequency generator output to the oscilloscope CH0 input. 2. Select the square wave output ( ) and set the frequency to 1 kHz. 5. Set the Amplitude to 5.00 Vpp and the DC Offset to 2.50 V. 6. On the oscilloscope, adjust the Time/Div setting to a value of 0.5 ms. 7. Set the Volts/Div to 2.0 V. 8. Press Run on both instruments. Sketch the observed waveform below. Label both axes and ground. Output Waveform for Step 4 1. Stop both instruments. 5. Generate and measure triangle waveforms.

2. Set the frequency generator to output a triangle wave ( ) with a frequency of 1.0 kHz, 6.00 Vpp, and 0 V DC Offset. 3. Set the oscilloscope to 2.0 V/div and 200 μsec/div. 4. Run both instruments and sketch the output below. Label the axes and ground. Output Waveform for Step 5 1. Measure and record the values below, including units. Vertical scale _____________ Horizontal scale______________ Period ________________ Frequency _________________ 1. Stop both instruments. 6. Generating and measuring sinusoidal waveforms. 6. Select a sine wave output with a frequency of 1 kHz, 6.0 Vpp, and 0 V DC Offset. 7. Record measurements displayed on the oscilloscope display, including units. Vertical scale _____________ Horizontal scale______________ Peak +V = ________________ Frequency = ________________ 1. Component Identification Go through your parts kit and identify the various components and tools you have. Application and proper use will be demonstrated in video clips and discussed in the Lab Q & A thread. 1. 2. After verifying that your lab kit is complete, select two components and find out what they are and what they do. HINT—Use the instruction manual, illustrated parts list, the campus library and/or the Internet to guide you toward the answers. Record the part numbers and functions below. First device’s part number or physical description _________________ First device’s function (what does it do?) Second device’s part number or physical description _________________ Second device’s function (what does it do?) 1.

TROUBLESHOOTING

Describe any problems encountered and how those problems were solved. **********************************************************

ECET 105 Week 2 Homework

For more classes visit www.snaptutorial.com 1. What is the duty cycle for a square wave signal that is HIGH for 15 nsec and LOW for 30 nsec? 2. A pulse train is shown on the oscilloscope below. Determine the period of the pulse. 3. Determine the frequency for a pulse that occurs every 10 ms. 4. What is the base-10 value for the binary number 11012? 5. What are the respective weights of the 1s in Problem 4? 6. How many different values can be represented by 6 bits, 7 bits, 8 bits, and 10 bits? 7. What is the minimum number of bits required to represent each of the following decimal numbers: 10, 1,000, 100,000, and 1,000,000? 7. Convert the binary value, 1011010100101101, to a hexadecimal equivalent. 9. Convert the following decimal numbers to 8-bit binary values. For negative numbers, use the 2â&#x20AC;&#x2122; complement formulation. 10. Express each of the following signed numbers (2s complement format) in decimal:

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ECET 105 Week 2 iLab Soldering Techniques and the Electronic Die Kit

For more classes visit www.snaptutorial.com I. OBJECTIVES 1. To learn the basics of soldering. 2. To produce mechanically and electrically sound solder joints. 3. To assemble the Electronic Die Kit. II. PARTS LIST Equipment: Digital Die Kit Tools: 1 – Soldering Iron 1 – Pair Long-Nose Pliers 1 – Diagonal cutter 1 – Solder and hookup wire 1 – Wire stripper III. PROCEDURE 1. Preparation 2. Prepare a well-ventilated and clear workspace with ample lighting.

3. Ensure that the workspace includes a mat to work on in order to prevent the burning of the table or materials during the process. 4. Use a tray, egg crate, or vegetable/fruit tray for all (but especially the small) parts to avoid losing them. Attach the tray with double-sided tape to your bench or desktop. 5. Have a waste basket or desktop trash receptacle handy. 6. Ensure that the sponge that accompanies the soldering iron is sufficiently damp. The level of dampness needed is judged by wetting the sponge and then squeezing out the excess water until the sponge can be held in the hand with no noticeable water dripping from it. CAUTION: In order to avoid injury to the eyes, goggles or other eye protection must be worn AT ALL TIMES during the circuit assembly and soldering process. A soldering iron at temperature is very hot. It is a fire hazard. It is a health hazard. Caution must be taken at all times to ensure that contact with the skin does not occur. 6. Plug in the soldering iron and wait approximately five minutes for the iron to heat to a proper temperature. The temperature of the iron may be tested by lightly rubbing the tip of the iron against the moist sponge. If a majority of water is evaporated, then the iron is ready for use. The tip should be kept clean and tinned for soldering. The sponge is used to wipe away excess solder and materials. Tinning means that there is always a thin layer of solder on the tip. 7. Procure and prepare the dice kit for soldering. Inventory the parts and materials and ensure that each part fits the circuit board correctly by checking the parts on the board WITHOUT soldering them to the board. Put them in the tray until ready to install. 8. Prepare the tools that you will need: soldering iron, rosin core solder, desolder wick, safety glasses, long-nose pliers, and wire cutters. 1.

Assembling the Electronic Die Kit

7. Inspect the Atmel ATTINY85-20PU microcontroller. Straighten any severely bent pins, very slowly; otherwise, they could break. Align the IC on your breadboard so that the dot in the top lefthand corner of the IC is at the same end as the notch in the IC socket. Insert the pins on one side, but do not press in, making sure that each pin is started in its socket. Gently press the IC from the other side against the pins started until the pins on the other side easily start in their sockets. Double check that no pin is bent under or is outside of its intended socket location. Press the IC into the socket, firmly but gently. 2. Attach the 9V battery firmly to the battery connector. 3. The die kit should resemble Figure 4.1 when assembly is completed. The Atmel ATTINY85-20PU has been shipped with a program already stored so that the die may be tested by connecting the 9V battery to the connector, then pressing and holding the momentary switch and releasing it. While the switch is pressed, the LEDs will blink in a random pattern. When the switch is released, a randomly generated number between 1 and 6 will be displayed on the LED die. Note any performance issues. Hints: If the die is not working on the first try, turn it off by unplugging the battery. Check for warm/hot components. If the regulator U1 is hot, you have a short somewhere. Look for solder shorts, incorrectly inserted components, and leads that may be touching adjacent leads. Remove the shorting connection and try again. **********************************************************

ECET 105 Week 3 Homework

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www.snaptutorial.com 1. Determine the output X for the 2-input AND gate with the input waveforms shown. 2. Determine the output X for the 2-input OR gate with the input waveforms shown. 3. Determine the output X for the 2-input Exclusive-OR gate with the input waveforms shown 4. Determine the output X for the 2-input NAND gate with the input waveforms shown. 5. Is the output from the NAND gate shown in Problem 4 active-HIGH or active-LOW? Why? 6. Download from a semiconductor manufacturerâ&#x20AC;&#x2122;s website (such as ti.com) the data sheet for a DIP packaged quad NOR gate (74x02). What pins does this chip use for the inputs to the first gate? 7. Draw a logic circuit that performs the following Boolean expression: Y = A * B. 8. Draw a logic circuit that performs the following Boolean expression: 9. Which gate is represented by the truth table below? 10. Use a truth table to determine the function of the gate shown below. **********************************************************

ECET 105 Week 3 iLab Introduction to Digital Logic Gates

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www.snaptutorial.com I.

OBJECTIVES 1. To understand basic logic functions (AND, OR, and NOT) and their complement used in Boolean algebra and digital logic design. 2. To test simple logic small-scale integration (SSI) integrated circuit (IC) devices. II. PARTS LIST Equipment: IBM PC or Compatible with Windows 2000 or Higher Parts: 1 – 74LS00 Quad 2-Input NAND Gate IC 1 – 74LS02 Quad 2-Input NOR Gate IC 1 – 74LS04 Hex INVERTER Gate IC 1 – 74LS08 Quad 2-Input AND Gate IC 1 – 74LS32 Quad 2-Input OR Gate IC 1 – 74LS86 Quad 2-Input XOR Gate IC 1 – Set of Four Single-Pole-Double-Throw (SPDT) Switches, DIP Style 1 – 330 Ω resistor 1 – Light emitting diode (LED), red III. PROCEDURE 1. OR Gate Operation 1. Using the Internet or the campus library, acquire a hard copy of a data sheet for the 74LS32 quad 2-input OR gate. (HINT: Look at ti.com for possible help.) One of the OR gates is shown below in Figure 5.1. Figure 5.1 – 2-Input OR Gate 2. Fill in the Table 5.1 for ALL possible logic conditions, based on the information found on the data sheet. 3.

Input (Pin 1)

Input (Pin 2)

Output (Pin 3)

Table 5.1 - 2-Input OR Gate Theoretical Truth Table 3. Write the Boolean expression below for the relationship between the device inputs (labeled as A and B) and output (labeled as Y). OUTPUT Y = ____________________________ 4. Construct the circuit shown in Figure 5.2 (a layout of the breadboard is shown in Figure 5.3). Be sure that the flat side of the LED (called the cathode) is connected to ground and that the 74LS32 is connected to power and ground (Pins 14 and 7, respectively). Figure 5.2 – OR Gate Test Circuit Top View Side View Figure 5.3 – Breadboard Layout for Figure 5.2 5. Connect the circuit to verify the logic gate operation recording the input and output voltages. Fill in Table 5.2below for ALL possible logic conditions. Input (Pin 1) Input (Pin 2) Output (Pin 3) Table 5.2 - 2-Input OR Gate Measured Truth Table Do the results match the manufacturer’s truth table? __________ (YES or NO) 1. AND Gate Operation 2. Acquire a hard copy of a data sheet for the 74LS08 quad 2-input AND gate. Figure 5.4 – 2-Input AND Gate 2. Fill in the truth table below for ALL possible logic conditions based on the information found on the data sheet. Input (Pin 1) Input (Pin 2) Output (Pin 3) Table 5.3 - 2-Input AND Gate Theoretical Truth Table 3. Write the Boolean expression below for the relationship between the device inputs (labeled as A and B) and output (labeled as Y). OUTPUT Y = ____________________________

4. Construct the circuit shown in Figure 5.5 by replacing the 74LS32 from Figure 5.2 with a 74LS08. Figure 5.5 - 2-Input AND Gate Test Circuit 5. Connect the circuit to verify the logic gate operation recording the input and output voltages. Fill in the truth table below for ALL possible logic conditions. Input (Pin 1) Input (Pin 2) Output (Pin 3) Table 5.4 - 2-Input AND Gate Measured Truth Table Do the results match the manufacturer’s truth table? __________ (YES or NO) 1. NAND Gate Operation 2. Acquire a hard copy of a data sheet for the 74LS00 quad 2-input NAND gate. Figure 5.6 – 2-Input NAND Gate 2. Fill in Table 5.5 for ALL possible logic conditions, based on the information found on the data sheet. Input (Pin 1) Input (Pin 2) Output (Pin 3) Input (Pin 1) Input (Pin 2) Output (Pin 3) Input (Pin 1) Input (Pin 2) Output (Pin 3) Table 5.5 - 2-Input NAND Gate Theoretical Truth Table 3. Write the Boolean expression below for the relationship between the device inputs (labeled as A and B) and output (labeled as Y). OUTPUT Y = ____________________________ 4. Construct the circuit shown in Figure 5.7 by replacing the 74LS08 from Figure 5.5 with a 74LS00. Figure 5.7 – 2-Input NAND Gate Test Circuit 5. Connect the circuit to verify the logic gate operation recording the input and output voltages. Fill in the truth table below for ALL possible logic conditions. Input (Pin 1) Input (Pin 2) Output (Pin 3) Table 5.6 - 2-Input OR Gate Measured Truth Table

Do the results match the manufacturer’s truth table? __________ (YES or NO) 1. Exclusive-OR Gate Operation 2. Acquire a hard copy of a data sheet for the 74LS86 quad 2-input exclusive-OR (XOR) gate. Figure 5.8 – 2-Input XOR Gate 2. Fill in the truth table below for ALL possible logic conditions, based on the information found on the data sheet. Input (Pin 1) Input (Pin 2) Output (Pin 3) Table 5.7 - 2-Input XOR Gate Theoretical Truth Table 3. Write the Boolean expression below for the relationship between the device inputs (labeled as A and B) and output (labeled as Y). OUTPUT Y = ____________________________ 4. Construct the circuit shown in Figure 5.9 by replacing the 74LS00 from Figure 5.7 with a 74LS86. Figure 5.9 – 2-Input XOR Gate Test Circuit 5. Connect the circuit to verify the logic gate operation recording the input and output voltages. Fill in the truth table below for ALL possible logic conditions. Input (Pin 1) Input (Pin 2) Output (Pin 3) Table 5.8 - 2-Input OR Gate Measured Truth Table Do the results match the manufacturer’s truth table? __________ (YES or NO) 1. NOR Gate Operation 2. Acquire a hard copy of a data sheet for the 74LS02 quad 2-input NOR gate. Figure 5.10 – 2-Input NOR Gate 2. Fill in the truth table below for ALL possible logic conditions, based on the information found on the data sheet. Input (Pin 2) Input (Pin 3) Output (Pin 1) Table 5.9 - 2-Input NOR Gate Theoretical Truth Table 3. Write the Boolean expression below for the relationship between the device inputs (labeled as A and B) and output (labeled as Y). OUTPUT Y = ____________________________

4. Construct the circuit shown in Figure 5.11. Note that the pin numbers for inputs and outputs have changes from Figure 5.9 (output is now Pin 1, inputs are on Pins 2 and 3). Figure 5.11 – 2-Input NOR Gate Test Circuit 5. Connect the circuit to verify the logic gate operation recording the input and output voltages. Fill in the truth table below for ALL possible logic conditions. Input (Pin 2) Input (Pin 3) Output (Pin 1) Table 5.10 - 2-Input NOR Gate Measured Truth Table Do the results match the manufacturer’s truth table? __________ (YES or NO) 1. NOT Gate Operation 2. Acquire a hard copy of a data sheet for the 74LS04 hex NOT gate. Figure 5.12 – NOT Gate 2. Fill in the truth table below for ALL possible logic conditions, based on the information found on the data sheet. Input (Pin 2) Input (Pin 3) Output (Pin 1) Table 5.11 - NOT Gate Theoretical Truth Table 3. Write the Boolean expression below for the relationship between the device input (labeled as A) and output (labeled as Y). OUTPUT Y = ____________________________ 4. Construct the circuit shown in Figure 5.13. Note that the pin numbers for inputs and outputs have changes from Figure 5.11 (output is now Pin 2, input is on Pin 1). Figure 5.13 – 2-Input NOR Gate Test Circuit 5. Connect the circuit to verify the logic gate operation recording the input and output voltages. Fill in the truth table below for ALL possible logic conditions. Input (Pin 1) Output (Pin 2) Table 5.12 - NOT Gate Measured Truth Table Do the results match the manufacturer’s truth table? __________ (YES or NO) 1. TROUBLESHOOTING

Describe any problems encountered and how those problems were solved.

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ECET 105 Week 4 Homework

For more classes visit www.snaptutorial.com 1. Draw a logic circuit that performs the following Boolean expression: 2. Determine the Boolean expression for the circuit shown below. 3. The Boolean expression for an AND gate is . Does the expression also describe an AND gate? Prove your answer. 4. Write the Boolean expression for the logic circuit shown below. 5. Develop the truth table for the circuit shown in Problem 4. 6. Develop the truth table for the circuit shown below. 7. Develop the Boolean expression for the circuit shown in Problem 6. 8. Draw a logic circuit using only NAND gates to implement the following Boolean expression: Y =AB + C. 9. Develop a logic circuit, using only NAND gates, to implement a circuit to meet the requirements of the truth table shown below. 10. Determine the Boolean description for the circuit shown below.

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ECET 105 Week 4 iLab Logic Circuit Design, Simplification, Simulation, and Verification

For more classes visit www.snaptutorial.com Objectives: 1. To design a digital logic circuit using a truth table and sum-ofproduct (SOP) formulation. 2. To use the MultiSim program to simplify, simulate, and test the circuit operation. 3. To build and test the logic circuit to verify that the system performs as expected. Results: Built a circuit board which would turn on the LED light and used multisim and tools which would simplify to do so. Verified the truth table to check and see if the vales are accurate.

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ECET 105 Week 5 Homework

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www.snaptutorial.com 1. Determine the decimal value of each of the following unsigned binary numbers: 2. Determine the decimal value of each of the following signed binary numbers displayed in the 2’s complement form: 3. Determine the outputs (Cout, Sout) of a full-adder for each of the following inputs: 4. The circuit below is an attempt to build a half-adder. Will the Cout and Sout function properly? Demonstrate your rationale. 5. Determine the outputs for the circuit shown below. Assume that C0 = 0 for all cases. 6. Derive the Boolean equation for A = B, when A and B are 4-bit numbers. 7. Complete the timing diagram below for a 2-bit adder. (10 points) 8. Answer the following: What is the frequency of a periodic waveform with a period of 1.0 µsec? How many bits are required to represent decimal numbers from -256 to +255? What is the largest positive number that can be represented by 10 signed bits? 9. The full-adder shown below is tested under all input conditions as shown. Is the circuit operating correctly? If not, what is the most likely fault? 10. Using a 4-bit adder/subtractor, carry out the binary operations for 9 – 3 and 3 – 9. What can you conclude about the answers and the carry out bit (C4)?

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ECET 105 Week 5 iLab Designing Adders and Subtractors

For more classes visit www.snaptutorial.com Objectives: The objectives are to reinforce the concepts of binary addition/subtraction while using the Quartus II Programmable Logic Tool as well as getting used to the program. We were also supposed to build and test a simple adder/subtractor using the eSOC III Board. Observations/Measurements: Describe any problems you had with this weekâ&#x20AC;&#x2122;s assignment. 1. In the simulation run of the four-bit adder, when we performed the addition 5 + 3, we did not immediately have an output of 8 on SOUT. What could be the cause of this? 2. If we changed the count period to 1000 nS for A and B, would this correct the anomalies in Question 1? Why or why not? 3. How fast can your 4-bit adder/subtractor determine the sum or difference of two numbers? 4. Use the simulation timing diagram to compare the worst case time to do an operation with your adder/subtractor with the worst case using the 74LS283. State which operation takes the longest and list the time required for both devices.

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ECET 105 Week 6 Homework

For more classes visit www.snaptutorial.com 1. When a HIGH is on the output of the decoding circuit below, what is the binary code appearing on the inputs? 2. Write the Boolean equations for each of the following codes if an active-LOW decoder output is required. The first decode is shown as an example. 3. What are the active outputs of a BCD-to-7 segment decoder with an input of 0100? 4. A 7-segment decoder/driver drives the display below. Using the waveforms shown, determine the sequence of digits that appear on the display. 5. Construct a truth table for an active-LOW output BCD (1-of-10) decoder. 6. Derive the truth table for the Y output in the diagram below. 7. Derive the Boolean equation for the Y output in Problem 6. 8. For the multiplexer shown below, determine the output for the following input state. D0 = 0, D1 = 1, D2 = 1, D3 = 0, S0 = 1, S1 = 0. 9. Determine the function of the circuit shown below. 10. Write the Boolean equation for the circuit shown in Problem 9. **********************************************************

ECET 105 Week 6 iLab Decoders and Multiplexers

For more classes visit www.snaptutorial.com Objectives: 1. To learn about the operation of a BCD-to-seven-segment decoder 2. To learn about the operation of a seven-segment display 3. To learn about the operation of multiplexers 4. To build and test a multiplexed display circuit using both discrete components and the eSOC III board Questions: Why are the 330 Ω resistors required for the discrete logic circuit, but not for the MultiSim simulated circuit or the eSOC III circuit? Create a partial truth table showing the requirements for a sevensegment decoder to output a hexadecimal digit. This requires four input bits and six output states, A – F. For each output state, show the segments a-g. The output states for the inputs 0 – 9 are the same as for the 74LS47 (see focus.ti.com). Use capital letters A, C, E, F and lower case for b and d. Why is the seven-segment display driven with an active-LOW signal using discrete logic and an active-HIGH with the eSOC board?

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ECET 105 Week 7 Homework

For more classes visit www.snaptutorial.com 1. Sketch the Q output for the waveforms shown. Assume that Q starts LOW. 2. Sketch the Q output for the circuit shown below. Assume that Q starts LOW. 3. Sketch the Q output for the circuit shown below. Assume that Q starts LOW. 4. Sketch the Q output for the circuit shown below. Assume that Q starts LOW. 5. Sketch the Q output for the circuit shown below. Assume that Q starts LOW. 6. Sketch the Q output for the circuit shown below. Assume that Q starts LOW. 7. Sketch the Q output for the circuit shown below. Assume that Q starts LOW. 8. Sketch the Q0 and Q1 outputs for the circuit shown below. Assume that both Q0 and Q1 start LOW. 9. What is the output frequency for Q1 in the circuit shown below? 10. What is the output frequency for Q2 in the circuit shown below?

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ECET 105 Week 7 iLab Add-Subtractor using Flip-Flops

For more classes visit www.snaptutorial.com I.

OBJECTIVES 1. To test the operation of a 74LS74 D flip-flop and compare the operation with the predicted behavior 2. To test the operation of a 74LS112 J-K flip-flop and compare the operation with the predicted behavior 3. To measure propagation delays of a 74LS112 J-K flip-flop 4. To build and test an enhanced adder-subtractor II. PARTS LIST Equipment: IBM PC or Compatible with Windows 2000 or Higher Quartus II Design Software—Version 9.1 Frequency Generator Oscilloscope Parts: 2 – 330 Ω resistors, ¼ W 2 – Red LEDs 1 – 74LS74 dual D flip-flop 1 – Green LED 1 – 74LS112 dual J-K flip-flop 1 – SPDT Switch, DIP configuration 1 – eSOC III FPGA Board III. PROCEDURE A. Test the 74LS74 D Flip-Flop

Build the D flip-flop circuit shown in Figure 7.1. The LEDs are wired as active-LOW since the flip-flop can supply more current in a low state than in a high state. This means that the green LED is on when is HIGH and the red LED indicates Q is HIGH. Remember to attach VCC to pin 14 and ground to pin 7. Using the circuit, verify that the operation follows the truth table for this device. What happens when both and are set low? Build the J-K flip-flop circuit shown in Figure 7.2. Remember to attach VCC to pin 16 and ground to pin 8. Using the circuit, verify that the operation follows the truth table for this device. Increase the pulse generator output to 1.0 MHz. Set the switches so that all of the flip-flop inputs are high and remove the LEDs and resistors. Using the oscilloscope, measure the propagation times for the Q output from the active clock edge. Record the value below. Using Quartus II, modify the circuit from Lab 5 as shown in Figure 7.3 by adding three 7474 D-flip-flip chips. Note that a clear function has been added and that the flip-flop presets are inactive since they are tied to +5V (labeled VCC). Perform a simulation to verify the correct operation of the circuit. Note that in this case, the CLOCK signal is not a periodic signal; the CLOCK signal is a discrete signal occurring on a switch closure. Assign pins to the inputs and outputs. Use the DIP switches for your inputs (0-3 for A, 8-11 for B, 7 for CLEAR, 15 for ADDSUB), one of the debounced pushbuttons for CLOCK and the red LEDs for outputs (RD0-4). Download you program to the eSOC III board and test the operation of the circuit. Photograph your final circuit for submission (online) or demonstrate your circuit to your professor (onsite or blended). Why is the condition when both and are LOW considered illegal?

How do the values you measured for tPHL and tPLH compare with values specified in the 74LS112 data sheet? You may need to go online to find this value. Why were the LEDs removed before making the propagation delay measurements?

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ECET 105 Possible is Everything/snaptutorial.com

or more classes visit www.snaptutorial.com 1. Does a typical computer have any analog outputs? If so, what are they? 2. List three advantag...

ECET 105 Possible is Everything/snaptutorial.com

or more classes visit www.snaptutorial.com 1. Does a typical computer have any analog outputs? If so, what are they? 2. List three advantag...