STM32 Project Quick Start

TL;DR: Edit main.c and run. That’s basically it.

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Your Project Folder

Unit_3_1_LCD_Test/
├── Core/Src/main.c          ← <<< EDIT THIS
├── Core/Inc/main.h
├── Drivers/                  ← Don't touch
├── ST7789V2_Driver_STM32L4/  ← Don't touch (LCD functions)
└── build/                    ← Don't touch (auto-generated)

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What To Do

1. Open Core/Src/main.c

This is your program. It looks like:

int main(void) {
    HAL_Init();
    SystemClock_Config();
    MX_GPIO_Init();
    
    // ← Write your code here!
    
    while(1) {
        // ← Or here for loops
    }
}

2. Use These Functions

Display:

#include "LCD.h"

LCD_init();                          // Start the display
LCD_Draw_Circle(x, y, radius, color); // Draw circle
LCD_printString(x, y, "Hello", color); // Draw text
LCD_Refresh();                       // Show changes

Hardware:

HAL_GPIO_WritePin(port, pin, state);  // Digital output
HAL_GPIO_ReadPin(port, pin);          // Digital input
HAL_Delay(milliseconds);              // Wait
printf("Debug: %d\n", value);         // Serial output

3. Build & Run

• Click the Build button (hammer icon)
• Click Run button
• Done!

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Files You Might Edit

File	When?
main.c	Always - your code goes here
main.h	Sometimes - for global variables/functions
.ioc file (in CubeMX)	Only if changing hardware pins

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Files to Leave Alone

• Drivers/ - External libraries
• ST7789V2_Driver_STM32L4/ - LCD driver
• build/ - Auto-generated output
• Everything with “auto-generated” in the comment

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Common Questions

Q: Do I need to understand the whole project structure? No! Just focus on main.c. Everything else “just works.”

Q: Where do the LCD functions come from? From the ST7789V2_Driver_STM32L4/ folder. Just #include "LCD.h" and use them.

Q: My code isn’t working. Where do I debug?

1. Check main.c for typos
2. Use printf() to print debug info
3. See Full Guide for more details

Q: What happens when I press Build?

1. Compile - Your .c files get turned into machine code the board can run
2. Link - All the pieces (your code + libraries) get connected together
3. Output - A .elf file is created in the build/ folder (this is your program)
4. Upload - VS Code flashes it onto the microcontroller

If there are errors, VS Code shows them. Fix the error and press Build again. It’s fast - usually takes 2-5 seconds!

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Next Steps

• Check the LCD Library Reference for available functions
• Look at example projects in the Unit_3_1_LCD_Test repo
• Read the Full Project Guide if you want to understand the deep structure

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Need More Details?

The Full Project Structure Guide explains everything in detail - but you don’t need it to get started!