Raspberry Pi Pico/CircuitPython + ssd1306 I2C OLED using adafruit_displayio_ssd1306 driver

This example run on Raspberry Pi Pico/CircuitPython, to display on 128x64 I2C OLED Display using adafruit_displayio_ssd1306 driver.

It's assumed the CircuitPython is installed on Raspberry Pi Pico, current CircuitPython 6.2.0-beta.2 is installed in this exercise. Refer to the post to "Install CircuitPython firmware on Raspberry Pi Pico".

Library:

In this exercise, adafruit_displayio_ssd1306 and adafruit_display_text of Adafruit CircuitPython Library Bundle is needed.

Visit https://circuitpython.org/libraries, download the appropriate bundle for your version of CircuitPython.

Unzip the file, copy adafruit_displayio_ssd1306.mpy and adafruit_display_text folder to the lib folder on your CIRCUITPY drive.

Connection:

Example code:

cpyPico-ssd1306-displayio-20210216a.py

import os
import time
import busio
import board
import displayio
import terminalio
import adafruit_displayio_ssd1306
from adafruit_display_text import label

WIDTH = 128
HEIGHT = 64
CENTER_X = int(WIDTH/2)
CENTER_Y = int(HEIGHT/2)

displayio.release_displays()

SDA = board.GP8
SCL = board.GP9
i2c = busio.I2C(SCL, SDA)

if(i2c.try_lock()):
    print("i2c.scan(): " + str(i2c.scan()))
    i2c.unlock()
print()

display_bus = displayio.I2CDisplay(i2c, device_address=60)
display = adafruit_displayio_ssd1306.SSD1306(display_bus, width=128, height=64)
"""
“displayio” drivers will also work with CircuitPython to display error messages
and other output to the display when the user code is not using it.
"""
print("Raspberry Pi Pico/CircuitPython ")
print("SSD1306 displayio (adafruit_displayio_ssd1306)")
time.sleep(0.5)

print()
print("os.uname():")
uname = os.uname()
for u in uname:
    print(u)
    time.sleep(1)

print()
print(adafruit_displayio_ssd1306.__name__ + " : " + adafruit_displayio_ssd1306.__version__)
print()
#================================================
# Make the display context
group = displayio.Group(max_size=10)

NUM_OF_COLOR = 2
bitmap = displayio.Bitmap(WIDTH, HEIGHT, NUM_OF_COLOR)
bitmap_palette = displayio.Palette(NUM_OF_COLOR)
bitmap_palette[0] = 0x000000
bitmap_palette[1] = 0xFFFFFF

tileGrid = displayio.TileGrid(bitmap,
                              pixel_shader=bitmap_palette,
                              x=0, y=0)
group.append(tileGrid)
display.show(group)

"""
print("bitmap: ")
print(type(bitmap))
print(dir(bitmap))
print("bitmap_palette")
print(type(bitmap_palette))
print(dir(bitmap_palette))
print("tileGrid")
print(type(tileGrid))
print(dir(tileGrid))
print("group")
print(type(group))
print(dir(group))
print("display")
print(type(display))
print(dir(display))
"""

time.sleep(1)
bitmap.fill(1)

def range_f(start, stop, step):
    f = start
    while f < stop:
        yield f
        f += step
        
time.sleep(1)
for y in range_f(0, HEIGHT-1, 2):
    for x in range_f(0, WIDTH-1, 2):
        #print(str(x) + " : " + str(y))
        bitmap[x, y] = 0

time.sleep(1)
#========================================================
# Draw a label
text_group1 = displayio.Group(max_size=10, scale=3, x=0, y=0)
text1 = "Hello"
text_area1 = label.Label(terminalio.FONT, text=text1, color=0xFFFFFF)
text_group1.append(text_area1)
group.append(text_group1)

"""
print("text_group1:")
print(type(text_group1))
print(dir(text_group1))
"""

for xy in range(20):
    time.sleep(0.1)
    text_group1.x=xy
    text_group1.y=xy
#========================================================
#invert palette
time.sleep(1)
bitmap_palette[1] = 0x000000
bitmap_palette[0] = 0xFFFFFF

time.sleep(1)
y = 0
for x in range_f(0, WIDTH-1, 1):
    bitmap[x, y] = 0
    time.sleep(0.01)
x = WIDTH-1
for y in range_f(0, HEIGHT-1, 1):
    bitmap[x, y] = 0
    time.sleep(0.01)

y = HEIGHT-1
for x in range_f(0, WIDTH-1, 1):
    bitmap[x, y] = 0
    time.sleep(0.01)
x = 0
for y in range_f(0, HEIGHT-1, 1):
    bitmap[x, y] = 0
    time.sleep(0.01)

#invert palette
time.sleep(1)
bitmap_palette[0] = 0x000000
bitmap_palette[1] = 0xFFFFFF
#invert palette
time.sleep(1)
bitmap_palette[1] = 0x000000
bitmap_palette[0] = 0xFFFFFF

time.sleep(1)
bitmap.fill(1)
time.sleep(1)
for xy in range(20):
    time.sleep(0.1)
    text_group1.x=xy+20
    text_group1.y=xy+20
time.sleep(1)
print("- bye -")

Next:

~ RPi Pico/CircuitPython x AHT20+BMP280 (Temperature, Humidity and Pressure Sensor Module), display on ssd1306 I2C OLED

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In the display drivers of CircuitPython libraries: Pixel based displays are implemented in two different ways. The original method called “framebuf” uses a traditional frame buffer model where all pixels are stored in the microcontroller’s ram. The newer method called “displayio” generates the pixels on the fly and relies on the display’s ram to store the final pixels. “displayio” drivers will also work with CircuitPython to display error messages and other output to the display when the user code is not using it.

The library used in this exercise adafruit_displayio_ssd1306 is displayio library for ssd1306.

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Releasing Displays:

Once you've created your display instance, the CircuitPython firmware will remember the setup between soft resets. This helps facilitate showing the serial output on the display, which can be useful for seeing error messages, etc.. Because of this behavior, you may run into error issue.

To avoid this issue, you can use the release_displays() command in displayio. Call this before creating your display bus. 

ref: CircuitPython Display Support Using displayio  > Display and Display Bus

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