C07059 Advanced Embedded Systems and Internet of Things CW2 Assignment Brief | UNIVERSITY OF CHESTER

C07059 COURSEWORK BRIEF:

 This coursework accounts for 75% of your final mark of this module.             [Total 60 marks]

Section A: Lab session                                                 

To set up an STM32F303 microcontroller and MBedOS application shield. MBedOS will act as a layer of abstraction from the hardware. The main objective is to understand the communication between a microcontroller and sensor peripherals.

Please read the task and then follow the lab information to complete the task. You do not need to complete all the tasks. the final mark will be given based on your completion.

Tasks:

1)    Using RGB LEDs to Create a Flowing Light Effect (Based on Reference Code 01): (30%)
a.    Use Code 01 to understand the function of each line.
b.    Modify the code to implement your own customized LED flow pattern—for example, change the colour sequence, transition timing, or direction. Take photos to document the effect, include the modified code, and provide an explanation in your report. Compile the project and program the microcontroller. Include the build output in your report.
c.    Use the button to control the LED flow (reference Code 01.1).
d.    Further modify the code to customize the LED flow behaviour based on button input (e.g., change colours or sequence). Again, take photos, include your modified code, and explain the setup in your report.

2)    Using a Button and Potentiometer to Control LED Flow (Based on Reference Code 02): (30%)
a.    Study Code 02 to understand the function of each line. Modify the code to implement your own LED sequence and behaviour. Document the output using photos, and include the code and explanation in your report.
b.    Explain what happens when you change #define ACTIVE_LOW 1 to #define ACTIVE_LOW 0. Record the result and provide an explanation in your report.
c.    Attempt to modify the code to use pot2 (the second potentiometer) to control the LED brightness. If successful, include the code and a detailed explanation in your report.

3.) Integrating an LCD Display (Based on Reference Code 03): (40%)
a.    Import the C12832 LCD library (as demonstrated in the previous session).
b.    Use Code 03 to understand the function of each line. Take photos of the LCD display output, include the code, and provide an explanation in your report.
c.    Modify the LCD display content—for example, change the displayed text or message order. Document the result with photos and explain the modified code.
d.    Adjust the code to change the LCD refresh rate. Record the updated behaviour, include the modified code, and explain the change in your report.

Lab information:

MBedOS Application Shield:

The MBedOS application board acts as a shield to the Nucleo board. Simply connect the two together.

The STM32F303 microcontroller will read the acceleration and temperature values and display them. The initial microcontroller code with simply output an incrementing value to the LCD display. The interface for the C12832 LCD and MMA7660 Accelerometer Sensor will be achieved with MBedOS libraries.

1.    Go to https://os.mbed.com/ and make an account if you don’t have one. The IDE used in this lab is Keil Studio Cloud, an online IDE for MBed RTOS projects.

2.    After signing in you will be shown the IDE within the browser. Click File, New, and Mbed Project.

3.  In the new project configuration, select an empty Mbed OS project for MbedOS version 5. Do not use MbedOS version 6.

4.    Go into the Mbed libraries and change the MbedOS version to 5.10.0.

5.    Select the target as Nucleo-F303RE and build the project. Make sure that there are no errors in the IDE.

Code 01:

#include "mbed.h"// mbed Application Shield RGB LED pins DigitalOut ledR(D5);
DigitalOut ledG(D8); DigitalOut ledB(D9); int main() {

ledR = 0; ledG = 0; ledB = 0;

while (true) {
// Red
ledR = 1; ledG = 0; ledB = 0; wait_ms(500);
// Green
ledR = 0; ledG = 1; ledB = 0; wait_ms(500);
// Blue
ledR = 0; ledG = 0; ledB = 1; wait_ms(500);
// White
ledR = 1; ledG = 1; ledB = 1; wait_ms(500);
// Off
ledR = 0; ledG = 0; ledB = 0; wait_ms(500);
}
}

Code 01.1:

#include "mbed.h"
 
DigitalOut ledR(D5); DigitalOut ledG(D8); DigitalOut ledB(D9);

InterruptIn btn(D4);

volatile int mode = 0; // 0:Red 1:Green 2:Blue 3:White 4:Off volatile uint32_t last_press_ms = 0; // for debounceTimer t;

void applyMode(int m) {
// All off first
ledR = 0; ledG = 0; ledB = 0;

switch (m) {
case 0: ledR = 1; break; // Red
case 1: ledG = 1; break; // Green
case 2: ledB = 1; break; // Blue
case 3: ledR = 1; ledG = 1; ledB = 1; break; // White case 4: default: /* Off */ break; // Off
}
}

void onButtonPress() { uint32_t now = t.read_ms();
if (now - last_press_ms < 200) return; // debounce: 200ms last_press_ms = now;

mode = (mode + 1) % 5; applyMode(mode);
}

int main() { t.start();
 
btn.fall(&onButtonPress);

mode = 4; // start from OFF applyMode(mode);

while (true) { wait_ms(50);
}
}

Code 02:

#include "mbed.h"

#define ACTIVE_LOW 1

PwmOut ledR(D5); PwmOut ledG(D9); PwmOut ledB(D8);

AnalogIn pot(A0);

InterruptIn btn(D4);

volatile int mode = 4; volatile uint32_t last_ms = 0;

Timer t;

float pwmValue(float br) { if (br < 0.0f) br = 0.0f;
if (br > 1.0f) br = 1.0f;

#if ACTIVE_LOW
return 1.0f - br;
 
#else
return br; #endif
}

void setRGB(float r, float g, float b) { ledR.write(pwmValue(r)); ledG.write(pwmValue(g)); ledB.write(pwmValue(b));
}

void applyMode(float br) {
if (br < 0.02f || mode == 4) { setRGB(0.0f, 0.0f, 0.0f);
return;
}

switch (mode) {
case 0: setRGB(br, 0.0f, 0.0f); break; // Red case 1: setRGB(0.0f, br, 0.0f); break; // Green case 2: setRGB(0.0f, 0.0f, br); break; // Blue case 3: setRGB(br, br, br); break; // White default:setRGB(0.0f, 0.0f, 0.0f); break; // Off
}
}

void onButtonPress() { uint32_t now = t.read_ms();
if (now - last_ms < 200) return; // debounce last_ms = now;

mode = (mode + 1) % 5;
}

int main() {
 
t.start();

// PWM frequency ~1kHz ledR.period_ms(1); ledG.period_ms(1); ledB.period_ms(1);

// Button is usually active-low btn.fall(&onButtonPress);

while (true) {
float brightness = pot.read(); // 0..1 applyMode(brightness);
wait_ms(20); // smooth update
}
}.

Code 03:

#include "mbed.h" #include "C12832.h"

#define ACTIVE_LOW 1

// LCD on Application Shield
C12832 lcd(D11, D13, D12, D7, D10);

PwmOut ledR(D5); PwmOut ledG(D9); PwmOut ledB(D8);

AnalogIn pot1(A0); AnalogIn pot2(A1);

InterruptIn btn(D4);
 
volatile int mode = 4; volatile uint32_t last_ms = 0;

Timer t;

float pwmValue(float x) { // x:0..1 if (x < 0.0f) x = 0.0f;
if (x > 1.0f) x = 1.0f; #if ACTIVE_LOW
return 1.0f - x; #else
return x; #endif
}

const char* modeName(int m) { switch (m) {
case 0: return "RED"; case 1: return "GREEN"; case 2: return "BLUE"; case 3: return "WHITE"; default: return "OFF";
}
}

void setRGB(float r, float g, float b) { ledR.write(pwmValue(r)); ledG.write(pwmValue(g)); ledB.write(pwmValue(b));
}

void applyMode(float br) { switch (mode) {
case 0: setRGB(br, 0.0f, 0.0f); break; // Red only
 
 case 1: setRGB(0.0f, br, 0.0f); break; // Green only
 case 2: setRGB(0.0f, 0.0f, br); break; // Blue only
 case 3: setRGB(br, br, br); break; // White
 default: setRGB(0.0f, 0.0f, 0.0f); break; // Off
} 
} 

void onPress() {
uint32_t now = t.read_ms();
if (now - last_ms < 200) return; // debounce last_ms = now;
mode = (mode + 1) % 5;
}

int main() { t.start();
ledR.period_ms(1); ledG.period_ms(1); ledB.period_ms(1);

btn.fall(&onPress);

while (true) {
float br = pot1.read(); applyMode(br);

int brPct = (int)(br * 100.0f + 0.5f);

lcd.cls();
lcd.locate(0, 0);
lcd.printf("Mode: %s", modeName(mode)); lcd.locate(0, 10);
lcd.printf("Brightness: %d%%", brPct);

wait_ms(300);
 
}
}.

Section B: Report.

[Total 40 marks]

For this section, you will create a report explaining the code and results of the lab session. You will then perform a small research tasks to investigate other sensors for any embedded system case study of your choosing. This will require an investigation into the application of a sensor and its datasheet.

1) Investigate additional sensors:
a. Choose a case study/application which uses accelerometer, temperature sensor, and two other sensors of your choosing. Be exact with your sensor choice and reference data sheets.
b. Use data sheets, open-source code, and reference designs (example: STMicroelectronics discovery boards) to explain the implementation of the sensors.
c. Does your sensor use I2C, SPI, UART, ADC, etc? explain its method of communication. Example: for I2C communication explain its I2C address, command bytes for configuration, data register addresses, and any formula required to transform the data into the sensor value.

This is an open task, which fully dependents on your own research, learning and understanding. You
don’t need to cover every type of sensor and you can chose a few to analyse and descibe the best.

Ensure that all code developed is placed into an appendix at the end of your report.

END OF PAPER

MARKING CRITERIA

COURSEWORK WILL BE MARKED ACCORDING TO THE FOLLOWING UNIVERSITY CRITERIA.

90-100%: a range of marks consistent with a first where the work is exceptional in all areas;

80-89%: a range of marks consistent with a first where the work is exceptional in most areas.

70-79%: a range of marks consistent with a first. Work which shows excellent content, organisation and presentation, reasoning and originality; evidence of independent reading and thinking and a clear and authoritative grasp of theoretical positions; ability to sustain an argument, to think analytically and/or critically and to synthesise material effectively.

60-69%: a range of marks consistent with an upper second. Well-organised and lucid coverage of the main points in an answer; intelligent interpretation and confident use of evidence,

examples and references; clear evidence of critical judgement in selecting, ordering and analysing content; demonstrates some ability to synthesise material and to construct responses, which reveal insight and may offer some originality.

50-59%: a range of marks consistent with pass; shows a grasp of the main issues and uses relevant materials in a generally business-like approach, restricted evidence of additional reading; possible unevenness in structure of answers and failure to understand the subtler points: some critical analysis and a modest degree of insight should be present.

40-49%: a range of marks which falls short of pass, fail; demonstrates limited understanding with no enrichment of the basic course material presented in classes; superficial lines of argument and muddled presentation; little or no attempt to relate issues to a broader framework; lower end of the range equates to a minimum or threshold pass.

30-39%: a fail; may achieve some learning outcomes but falls short in most areas; shows considerable lack of understanding of basic course material and little evidence of research.

0-29%: a fail; basic factual errors of considerable magnitude showing little understanding of basic course material; falls substantially short of the learning outcomes for compensation.