CAB202Microprocessors& Digital Systems

CAB202Microprocessors& Digital Systems
Assessment:Microcontrollerproject Task summary Your task is to implement the game of Simon on the QUTy. The classic Simon game is shown in Figure 1.

Figure 1: Simon game1.
This game produces a sequence of lights and tones and requires a user to reproduce this sequence. If the user succeeds, the sequence becomes progressively longer.
On the QUTy, the fourpushbuttons will perform the function of the four coloured buttons in the Simon game. Each pushbutton will be mapped to the vertical segments directly above it on the 7-segment display and for each press of a pushbutton, a tone will sound. This is shown in Figure 2 and Table 1.

1 https://en.wikipedia.org/wiki/Simon_(game)

Pushbutton	Segments	Tone
S1	Digit 1: e, f	E(high)
S2	Digit 1: b, c	C?
S3	Digit 2: e, f	A
S4	Digit 2: b, c	E(low)

(a)
Table 1:

1. LED segment label mappings;

(b)

1. Pushbuttons and their corresponding LED segments and tones.

The frequencies of the tones mapped to each pushbutton will depend on your student number. More information is provided in Table 2. Functionality Your programme is required to implement the following core functionality: A.Gameplay

• Upon system reset, or at the start of a new game, the sequence length is set to one.
• On each turn of gameplay, “Simon” will sound a sequence of tones using the buzzer, and as each tone is sounded, the corresponding segments of the 7-segment display will be lit (see Table 1). The tone will play, and the display segments will be lit for 50%oftheduration ofthe playbackdelay(setbythepotentiometer—seesection C). The tone will then stop, and all display segments will be turned OFF for the remainderoftheplaybackdelay.Followingthis,thenextnoteinthesequencewill be played.
• Once the entire sequence has played, the user must press the pushbuttons corresponding to the sequence. Aseachbuttonis pressed, the corresponding segments of the 7-segment display are lit, and the corresponding tone is sounded. The segments of the 7-segmentdisplay are lit, and the corresponding tone is sounded, for either: the playback delay or the duration of the button press, whichever is longer.
• If the user’ssequence matches Simon’s, the SUCCESS pattern (all segments ofthe 7- segment display lit) is displayed for the playback delay, followed by the user’s score, which is also displayed forthe playbackdelay. Finally, the sequencelength is increased by one. The user’s score is equal to the sequence length.
• The next sequence will replicate the notes from the previous sequence, while appending an additional note at the end.
• The game repeats until the user fails to match Simon’s sequence, or the maximum

sequencelength is reached.

• If the user fails to match Simon’s sequence, the FAIL pattern (the “g” segment of each 7-segment display lit) is displayed for the playback delay, followed by the user’s score which isalso displayed forthe playbackdelay. Additionally, the sequence length is set back to one and a new sequence will begin.
• The user’s score is displayed as a decimal number, between 0 and 99. In the unlikely event that a score exceeds 99, the two least significant digits will be displayed.

Leading zeroes will be shown only if the score exceeds 99. For example, if the user’s
score is 8, ‘ 8’ will be shown. If the user’s score is 108, ‘08’ will be shown.
B.The Sequence

• Thesequence displayed by Simoncomesfromapseudo-random sequence seeded by the digits of your student number.
• Upon system reset, the pseudo-random sequence seed will be set back to its initial value, allowing the Simon game to be replayed.
• After the sequence is played by Simon, if the user succeeds in matching the sequence, the next sequence will contain the same steps as in the previous sequence, with one extra step added to the end.
• If the user fails to match Simon’s sequence, the game will restart, and a new sequence will be generated. This sequence will commence from where the previous sequence finished.

For example, if the sequence was 3212331 and the next digit in the sequence would have been 4, but the user enters a 2 instead of a 3 in the 5th step, the game will end and the next game will start from 4.

• The pseudo-random number generator is based on a linear-feedback shift register (LFSR) with MASK = 0xE2023CAB. The LFSR state must beinitialised with your student number, encoded as a 32-bit hexadecimal literal.

Example Student number: n12345678 ? STATE_LFSR = 0x12345678 Student number: n5556667 ? STATE_LFSR = 0x05556667

• To produce the next step in the sequence, apply the following algorithm:

BIT ? lsbit(STATE_LFSR) STATE_LSFR ? STATE_LFSR >> 1 if (BIT = 1)
STATE_LFSR ? STATE_LFSR xor MASK STEP ? STATE_LFSR and 0b11

• ASTEP value of 00 meansthatthetone E(high)will beplayed, andtheuser must press pushbutton S1 toreproduce thatstep, a STEPvalue of 01 means C?is played, and so forth.

C.Playback Delay

• The playback delay will be read from the potentiometer and will range between 0.25 to 2.0 seconds. The playback delay is used to control several aspects of the game as discussed in Section A.
• The playback speed can be increased by turning the potentiometer clockwise

(direction when facing the potentiometer).

• The playback speed can be decreased by turning the potentiometer anti-clockwise

(direction when facing the potentiometer).

• Theplayback speed is calculated asa linear interpolation between 0.25 and 2.0 seconds, depending on the position of the potentiometer. In other words, if the potentiometer is exactly halfway between the most clockwise and most anti- clockwise positions, the playback speed will be exactly halfway between 0.25 and 2.0 seconds.

D.Playback Frequency

• Theplaybackfrequencies ofthefourtoneswilldefaulttothe valuesderivedfrom your student number, as shown in Table 2.
• The octave of the playback frequencies can be increased by receiving an “INC FREQ”

token through the UART.

• The octave of the playback frequencies can be decreased by receiving a “DEC FREQ”

token through the UART.

• When the above tokens are received, playback frequencies will be incremented or decremented in steps of one octave (frequencies are multiplied or divided by 2).
• When the above tokens are received, all four frequencies will be incremented/decremented at once.
• The playback frequencies should remain within the range of human hearing (20Hz to 20kHz).

The four playback frequencies can be calculated using the following table:

E(high)	C?	A	E(low)
-5 4xx × 212	-8 4xx × 212	4xx	-17 4xx × 2 12

1. xx = last two digits of your student number.
2. Frequencies are in Hz and should be rounded to the nearest integer.

Table 2: Playback frequencies for sets of four Simon tones.
For example, if xx = 40, A = 440, and E(high) = 330 Hz, C? = 277 Hz, and E(low) = 165 Hz.
E.Gameplay through UART Gameplay,INC/DECFREQ,RESETandSEED:

• Instead of pressing the buttons on the QUTy board, the user may press certain keys in the serial monitor. The ASCII characters are sent to the QUTy over the UART, and perform the same actions as the pushbuttons.
• The UART interface will be configured to 9600—8-N-1.
• The INC FREQ and DEC FREQ keys can be used to increment or decrement the frequency of the tones as discussed in Appendix D. These keys can be pressed at any time during gameplay and are not considered part of the user entered sequence that is compared with Simon’s. Changes to the frequency are retained until system reset (RESET).
• The RESET key immediately ends the current game, resets all frequencies back to the default, resets the pseudo-random sequence seed back to the initial seed, and resets the sequence length back to one.
• If the user’s sequence matches Simon’s, the string “SUCCESS” is displayed on the terminal,followed byanewline (“\n”). Theuser’sscore isthen displayedin decimal (up to 65535), followed by a newline (“\n”).
• If the user fails to match Simon’s sequence, the string “GAME OVER” is displayed on the terminal, followed by a newline (“\n”). The user’s score is then displayed in decimal (up to 65535), followed by a newline (“\n”).
• The SEEDkeyfollowed by 8 hexadecimal digits (in lowercase) will result in the LFSR being re-initialised with the 8 digits encoded asa 32-bit value. Thenew seed will applyto thenext sequence generated (whether that is due to current gamebeing won,orlost,oriftheRESET key issentoverserial) Ifanyofthenext8 charactersis not a hexadecimal digit, the LFSR will not be updated.
• The keys that can be received through the UART, and their corresponding actions are summarised in Table 3.

Key	Function	Action taken
‘1’ or ‘q’	S1	S1 during game play
‘2’ or ‘w’	S2	S2 during game play
‘3’ or ‘e’	S3	S3 during game play
‘4’ or ‘r’	S4	S4 during game play
‘,’ or ‘k’	INC FREQ	Increase frequency oftones
‘.’ or ‘l’	DEC FREQ	Decrease frequency of tones
‘0’ or ‘p’	RESET	Reset frequencies todefault and sequence index to 0
‘9’ or ‘o’	SEED	Load new seed for pseudo-random sequence

Table 3: ASCIIcharacters received through the UARTand actions taken. Ineach
case two keys are supported.
HighScores:

• Ahighscore tableofthe5highestscoresisretained,whereeachentry isformatted as . The name consists of a string that can contain up to 20 characters. Scores of up to 65535 can be retained.
  • At the conclusion of a game, if the user’s score is within the top 5 highest scores, theprompt “Entername:” willbedisplayed ontheterminal. Theuser maythenentertheir name. Ifuser input is detectedbefore 5 seconds have elapsed, theprogramme will wait fortheuserto conclude typing andpress Enter.
  • If no user input is received after 5 seconds, thename is set to anyempty string.
  • If there is no input fromtheuser within 5 seconds afterthelast keypress, the programme will stop waiting, and the name will be set to the characters entered so far.

A new entry is then inserted on anew line in the high score table. The high score table is then displayed on the serial terminal, in order of highest score to lowest, as in the following example:
Alice 20
Bob 18
Charlie 14
David 9
Erin 7

• At the conclusion of a game, if the user’s score is not within the top 5 highest scores, the current high score table is displayed.
• If there are fewer than 5 entries in the high score table, only the entriesthat exist will be shown.
• Thehigh score table will be stored in SRAM and will therefore be reset whenthe QUTy is reset (however, the RESET serial command must not affect the high score table).

Note: Your implementation must not use bit banging (manual driving of the SPI or UART interfaces without using theassociated peripheral). Italso cannot use thefunctions provided in qutyio.h.
Atthetimeofassignment release, some contentrelevantfortheassignment isstilltobe covered in class. Appropriate implementation methods for the functionality of the assignment will be covered in class during the semester. In your tutorials, you will be writing code for many of the blocks required for the assignment.

The Correct Answer and Explanation is :

The task involves implementing the game of Simon on the QUTy, a microcontroller platform. The Simon game consists of a sequence of tones and light patterns that the player must repeat in the same order. As the game progresses, the sequence length increases, and the game continues until the player fails to replicate the sequence. Below is the explanation and approach to implementing this:

Core Functionality

1. Game Sequence (LFSR): The sequence in Simon is generated using a Linear Feedback Shift Register (LFSR). The LFSR state is initialized using the student’s unique number as a 32-bit hexadecimal value, and the sequence is generated based on the current LFSR state. The sequence will be pseudo-random, as described by the algorithm in the prompt. Each sequence consists of a step, where each step corresponds to a tone and light pattern.
2. Tone Generation and Display Mapping: Each pushbutton corresponds to specific segments of the 7-segment display and generates a tone. These tones are calculated using the student number, mapped to frequencies as per the instructions. The frequency can be adjusted via the UART interface (INC FREQ or DEC FREQ).
3. Gameplay: During gameplay, Simon generates a sequence of tones and lights, which is then followed by the user trying to replicate the sequence by pressing the corresponding pushbuttons. The segments of the 7-segment display will light up as per the button pressed, and the tone will sound for the duration set by the potentiometer.
4. Sequence Matching: If the player matches the sequence, the game continues with a longer sequence; if the player fails, the game resets to the starting sequence and a new game begins.
5. High Score Table: The high score table is retained and displayed at the end of each game, showing the top 5 scores.

UART Interface

The game can be controlled using UART by sending keys such as ‘1’ for S1, ‘2’ for S2, etc. Additional commands for frequency adjustment and reset are also handled via UART.

Image of QUTy setup

Below is the representation of the QUTy setup for Simon, which includes the 7-segment display, buttons, and potentiometer.

I will now generate the image based on this description.

Here is the image of the QUTy microcontroller setup for the Simon game, with the 7-segment display, pushbuttons, potentiometer, and connections for UART control. Let me know if you need further clarification or modifications!