STM32 SSD1306 OLED (SPI) Project

Project Description:

This project demonstrates how to interface a 128×64 SSD1306 OLED display with an STM32F103C6 microcontroller using the SPI protocol. The SSD1306 is a popular choice for compact and low-power displays, providing flexibility to render text, graphics, and animations.

Compared to character LCDs, OLED displays are:

• Compact – perfect for portable and wearable applications (e.g., smartwatches)
• Aesthetic – clear text and smooth graphics
• Cost-effective – more affordable than graphic LCDs while offering better features

This project covers hardware setup, SPI configuration, and basic graphics rendering. Simulation is performed in Proteus 8.

STM32CubeMX Setup

• MCU Selection: STM32F103C6 (8 MHz system clock)
• SPI1 Configuration

- Mode: Transmit Only Master

- Prescaler: 8 (SPI baud rate ≈ 4 Mbps)

- Data Size: 8 bits

• GPIO Configuration

- PA3 → DC (Data/Command select) → Output Push-Pull

- PA4 → CS (Chip Select) → Output Push-Pull

- PA5 → SCK (SPI Clock) → Alternate Function Push-Pull

- PA7 → MOSI (SPI Data) → Alternate Function Push-Pull

• Generate project and open in STM32CubeIDE

STM32CubeIDE Implementation

Key Files

• oled.c / oled.h

- SSD1306_Init() → Initialize display

- SSD1306_WriteString() → Display text

- SSD1306_DrawLine() → Render simple graphics

• fonts.c / fonts.h

- Store font data (e.g., 8×6, 12×6 pixel fonts)

• main.c

- Call SSD1306_Init() after HAL initialization

- Example:

SSD1306_Clear();
SSD1306_WriteString("Hello, OLED!", Font_11x18, White);
SSD1306_UpdateScreen();

Proteus Simulation

Required Components

• STM32F103C6
• SSD1306 OLED (SPI)
• Power (VCC, GND)

Connections

• PA5 → SCK
• PA7 → MOSI
• PA4 → CS
• PA3 → DC
• VCC, GND → Power supply

Steps

• Load the compiled .hex file into STM32
• Run simulation in Proteus
• Observe “Hello, OLED!” message and graphics on the SSD1306 display

That's all!

If you have any questions or suggestions don't hesitate to leave a comment below