4. The authors of the USB Trojan article considered USB channels that support devices such as speakers and keyboards to be especially vulnerable. Why?

Part B: From circuit to simplified Q4. For the circuit shown below in Figure 1: (i) write the Boolean expression for the output F, (ii) derive the truth table for the expression F manually, (iii) Use Boolean algebra to simplify the expression, and then (iv) draw the circuit in Multisim for this simplified expression and (v) generate the truth table for the outputs using Multisim. Verify that your manual truth table for the simplified expression matches the simulated truth table for the simplified circuit. It would help if you lay out all your circuits the same way, as shown below, with precise vertical inputs.

Part C: K-maps Q5. For the K-map shown below in Figure 2: (i) Draw the k-map, mapping the 1s to generate a simplified equation SOP for the function (F), and (ii) re-draw the k-map, this time mapping the Os to generate a simplified POS. (iii) simulate the circuit for both SOP and POS in Multisim, then (iv) simulate the circuits by adding NOT gate to the POS output and generating the truth tables for both. Verify the truth tables are the same. Q6. The K-map is shown below in Figure 3. Re-draw the K-map in your report, apply and demonstrate the groupings required to minimise the expressions and then simulate the new reduced circuit using MultiSim.

Part D: Narrative design Q7. An Unmanned Aerial Vehicle (UAV) using four wheels sensors A, B, C, and D. Every two wheels are parallel to provide balance during landing, A//C, and B//D. Design the functional system for landing wheels. A circuit is required to indicate the status of the landing wheels before landing. A green LED display turns on if any parallel pairs or all four wheels are down; the switch will activate the system to prepare for landing. A red LED display turns on if all wheels, or the two parallel wheels, fail to come down properly before landing. Assume that its sensor produces a LOW voltage when a leg is down. When a landing wheel is stuck, its sensor has a HIGH voltage. Implement a circuit to meet this requirement.

Part E: Functional completeness Q8. For the circuit in Q7, re-design the Red LED circuit using NOT of the Green LED circuit. Prove your answer using Boolean Algebra and the equivalent Multisim circuits and truth tables. Correct PDF submission, student number as filename, with cover page and clear presentation:

Convert the following four binary numbers to their decimal equivalent: 0011 1110 1111001 b) Convert the following four decimal numbers to binary: 6 26 122

a) To measure the time of flight, we can use a digital stopwatch. This is just a 12-bit binary counter that starts at 000000000000 when the pulse is transmitted and increments (e.g. 000000000001, 000000000010, 000000000011, ...) at a rate of 10 kHz. What is the resolution of the stopwatch (i.e. smallest time step between adjacent values)? b) If the speed of sound is 340 m/s, how long will it take for my ultrasonic pulse to travel to and from an object located 10m away? c) What will be the counter value (in binary) when the pulse is received back at the sensor? d) As my stopwatch has finite resolution as in a), I don't know the exact time of flight from my measurement - I can only estimate a range based on adjacent digital bits. Based on my digital reading in c), I can only determine a distance range within which the object sits; what is this range in meters? As you can see, the finite stopwatch resolution becomes a finite distance resolution for the overall sensor. e) Given the 12-bit counter, what is the maximum distance-to-object I can measure before I run out of bits?

The diagram below shows a JK flip-flop comprising a D-type positive-edge triggered flip-flop, two AND gates, an OR gate and an inverter. By including an extra input ("J" and "K" compared to just "D") the JK provides more opportunities for logic minimisation than the D-type. The JK used to be the preferred flip-flop as it offers better opportunities for logic minimisation. With the advent of high levels of circuit integration this has been eclipsed in popularity by the D-type which offers advantages in terms of reduced design complexity.

4) We will now look at sensor data taken from an electrocardiogram (ECG) recording, which converts voltage on the skin surface to a digital code using an ADC. As with the data we looked at in Studio #3, this comes from the open- source MIT-BIH database on Physionet (although it is a different recording). The recorded ECG data is saved in HW2_Workbook.xlsx. A few notes: . In the first column, we have the sample number - the sensor ADC makes a voltage measurement 128 times per second, so the elapsed time between each sample is approximately 7.81 ms (e.g. 1/128). In the second column, we have a binary representation of the ADC voltage measurement. For positive numbers, this will look like normal binary encoding. For negative numbers, this uses an encoding scheme called "Two's Complement"; the details of this aren't important for now, but you are welcome to read more about this online. This binary format is standard for Excel, so we can use built-in functions to manage it. For the ADC recording, the smallest step (ie. least significant bit, LSB) is 0.005mV (e.g. 5uV). a) First, we can convert ADC code the decimal values using the =BIN2DEC() function. Go ahead and do this in the "ECG ADC Code (Decimal)" column. If you do this correctly, the first few values should be -10, -13, and -9. If you look down the column, you should also see a high peak value (local maximum) between samples 25 and 40; which sample number is this, and what is the peak value? b) If the ADC step size is 0.005mV, as described above, the original voltage recorded at each sample during the ECG measurement can be calculated (reconstructed) by multiplying the decimal ADC code by the step size. Go ahead and do this in the "ECG (mV)" column. What is the maximum voltage you see in the data set? c) To figure out the elapsed time at each sample, we can just multiply the sample number by the time step, which as described above is 1/128 7.18ms. Go ahead and do this in the "Elapsed Time (s)" column. Note that you can use (1/128) directly in your Excel calculations, and you don't need to approximate - Excel will manage the rounding, and this is more accurate. d) Finally, create a straight-line scatter plot of ECG (mV) vs Elapsed Time (s) for the first 5s of ECG recording. Make sure all axes are labeled, fonts and font sizes are clear and consistent, and overall formatting is professional. Also, for this plot, turn off the markers, so we just see the overall ECG waveform. Be sure to include a copy of this plot directly in your homework solution PDF that you upload.

1. You have an interview on the third floor of the Amazon building. To get to the third floor, you need to take an elevator. You knew that in the interview, they were going to ask you about an FSM problem, so you decided to practice using that elevator as an example. The building has a total of 4 floors (Hint: those will be your different states): Ground level, 1st floor, 2nd floor, and 3rd floor. Inside the elevator, you can press either UP (which takes you one floor up) or DOWN (which takes you one floor down), meaning that there are only 2 buttons (Hint: your input will need to be 1 bit to express those 2 options, you can call it "A"). The Amazon employees knew you were coming to the interview, so they put up a digital sign that will say: "Far" when you are on the Ground level and on the 1st floor, "Very close" when you are on the 2nd floor, and "Arrived" when you are on the 3rd floor (Hint: your output can be 3 different things which means you will need 2 bits to express it when using binary encodings, you can call them "X" and "Y"). Write: - The state transition diagram - The state transition table - The state transition table with binary encodings (show what each thing means, for example, State0 => 2 bits S, S=00) - Equations for the next states and outputs - Simplify those equations if you can - The state machine circuit