ECET 179 FINAL EXAM REVIEW QUESTIONS ANSWERED CORRECTLY LATEST UPDATE 2026

ECET 179 FINAL EXAM REVIEW QUESTIONS ANSWERED CORRECTLY LATEST UPDATE 2026 What is a register? - Answers A special memory location inside the microcontroller that allows us to configure the hardware. What does the Data Direction Register do? - Answers Configures port as an input or output What is the Port Register used for? - Answers It is used to output values from the microcontroller How does the Data Direction Register (DDR) influence the operation of the Port Register? - Answers When the DDR is configured as an input, the Port Register controls the internal pull-up resistors. What is the difference between the Port Register and the Pin Register? - Answers The Port Register is used to output values while the Pin Register is used to read values. What happens if you attempt to read an input from the wrong register? - Answers It depends, but more than likely you will read the status of the pull-up resistors. How do you configure a port to be an output? - Answers You write a 1 to the corresponding Data Direction Register bit. How do you configure a port to be an input? - Answers You write a 0 to the corresponding Data Direction Register bit. YAY onto Serial Transfer Details - Answers HIIIIIIII Use the following equation to calculate the composite value (12-bit number) for UBRR given a BAUD rate of 19200 and system clock of 6 MHz. UBRR = (Fclk / (BAUD*16)) - 1 - Answers 19 Determine the actual BAUD rate that would be produced when using the proper rounded value for UBR: BAUD = Fclk / (16* (UBRR+1) - Answers 18750 Determine the BAUD rate error for this proposed system: - Answers -2.34% Given a BAUD rate of 19200, how long is each bit? - Answers 52.08 microseconds (1/19200) How long does it take to send the entire serial character? - Answers 520.8 microseconds (1 start bit + 8 bits + 1 stop bit = 10 10 * 52.08 microseconds = 520.8 microseconds) Given a system clock of 6 MHz and a BAUD rate of 100, calculate the 12-bit UBRR value and then separate it into the UBRRL and UBRRH (you should have 3 values here) - Answers 12-bit = 3749 UBRRH = 14 = 0x0E UBRRL = 165 = 0xA5 Onto Analog to Digital Converters! - Answers Whoop Whoop! Reference Equation for LM34 Temperature Sensor (it is given on the paper) - Answers 5v 1 Degree F ---- x ------------- 255 10mV (could be 1023) For the rest of this one it will pretty much tell you where to plug the numbers into. - Answers YIPPEEEEEEE For sharp sensors, most of it is given to you, you just have to plug numbers to get the slope and use point-slope form. - Answers slope = y2-y1/x2-x1 How accurate/what is the resolution of the measurement? (equation) - Answers Absolute value of the slope! So, if I had a slope of -0.392, the accuracy would be 0.392 per ACD count Timers! - Answers Speed, I am speed. 1 winner. 42 losers. I eat losers for breakfast. What are the solution steps to measure a positive pulse with a timer? (8 steps) - Answers 1. Make sure the signal is low 2. Wait for the signal to go high 3. Clear the counter value 4. Start counting 5. Wait for the signal to go low 6. Wait for the signal to go high 7. Stop counting 8. Read number of ticks If the 16MHz base clock value was divided by 8 while making the measurement, how much time is represented by each timer tick? - Answers Prescaler 8 ---------- = ----------- = 2MHz base clock 1 ---------- = 0.5 microseconds 2MHz Assume that the pulse on the right was received from the sensor. If the length of the pulse was measured to be 10,000 ticks with a clock source of clk/8, how long in microseconds is the pulse? - Answers 10000 x 0.5 microseconds = 5000 microseconds or 5ms Given your answer to the previous question, how far away in cm is the object from the sensor? - Answers 86.2 cm Time in microseconds Distance (cm) = --------------- 58 How far away in inches is the object from the sensor? - Answers 33.8 inches Time in microseconds Distance (cm) = --------------- 148 What is the maximum distance that can be measured using Timer 1 with this sensor when the clock source is set to CLK/8? - Answers 565 cm 65535 x 0.5 = 32767.5 32767.5/58 = 565cm How does that number change if you used CLK/1024? - Answers 72,314 cm CLK/1024 Tick = 64 microseconds 65535 x 64 = 4194240 microseconds 4194240 microseconds/58 = 72,314 cm BINARY YAYYYYY - Answers decode that The binary number system is based on how many digits? - Answers 2 What is a bit in a binary system? - Answers A single digit in a binary value How would you say the number 1101 in binary? - Answers One, one, zero, one What is the base of this number 101 (subscript 10 idk how to subscript) and how do you know? - Answers It is a decimal number (based 10) because the subscript is 10 indicating the base. Convert the following binary numbers into their decimal equivalents: - Answers 001110 - Answers 14 011101 - Answers 29 101011 - Answers 43 111001 - Answers 57 101111 - Answers 47 - Answers 2845 Convert the following decimal numbers to their binary equivalent: - Answers 68 - Answers 1000100 102 - Answers 1100110 147 - Answers 252 - Answers 600 - Answers How many symbols are used in hexadecimal numbers and what are they? - Answers 16 - 0,1,2,3,4,5,6,7,8,9,A,B,C,D,E,F Convert the following hexadecimal numbers into their decimal equivalents: - Answers 27 - Answers 39 E7 - Answers 231 D32 - Answers 3378 7A - Answers 122 Convert the following hexadecimal numbers into their binary equivalents: - Answers 72 - Answers E - Answers 001110 32 - Answers D7A - Answers Convert the following binary numbers into their hexadecimal equivalents: - Answers