🖥️ 0.91‑inch OLED Display (128×32)

📌 Description

The 0.91‑inch OLED display is a small screen that can show text, numbers, and even simple graphics. It uses the SSD1306 driver chip and communicates with the microcontroller through I2C (only 4 pins: VCC, GND, SDA, SCL).

🎯 Use

In our projects, the OLED display is used to:

Show sensor readings (temperature, distance, light).
Display icons or small images.
Provide menus or status information for the robot.

👉 Think of the OLED as the robot’s mini monitor — it shows what the robot wants to communicate.

Module parameters

Pin name	Description
GND	GND (Power Input Negative)
VCC	VCC (Power Input Cathode)
SCL	Clock signal communication pin
SDA	Bidirectional data communication pins

Supply voltage: 3.3V/5V
Connection: PH2.0 terminal wire
Installation method: four-screw fixation

🖥️ Code Explanation

import machine
import oled128x64
from expression_picture import Heart

# Configure I2C communication (pins 26 = SCL, 5 = SDA)
i2c_extend = machine.SoftI2C(scl = machine.Pin(26), sda = machine.Pin(5), freq = 100000)

# Initialize OLED with SSD1306 driver, address 0x3c
oled = oled128x64.OLED(i2c_extend, address=0x3c, font_address=0x3A0000, types=0)

# Display a heart image at position (0,0), size 1
oled.image(Heart, x = 0, y = 0, size = 1)

Step by Step

import machine, oled128x64 → Tools for pins and OLED control.
from expression_picture import Heart → Imports a predefined heart image.
i2c_extend = machine.SoftI2C(...) → Sets up I2C communication using pins 26 (SCL) and 5 (SDA).
oled = oled128x64.OLED(...) → Initializes the OLED display with SSD1306 driver at address 0x3c.
oled.image(Heart, x=0, y=0, size=1) → Draws the heart image at the top‑left corner of the screen.

👉 Together, this program makes the OLED show a heart icon.

✅ Conclusion of the Test

If the OLED shows a heart image, the program is working correctly.
This test demonstrates how the robot can draw graphics on a small OLED screen.
Later, you can display text, sensor values, or even combine multiple icons to create menus and animations.