OLED displays can be driven with python using the various implementations in the
luma.oled.device package. There are several device classes available
and usage is very simple if you have ever used Pillow or PIL.
To begin you must import the device class you will be using and the interface class that you will use to communicate with your device:
In this example, we are using an I2C interface with a ssd1306 display.
from luma.core.interface.serial import i2c, spi, parallel, pcf8574 from luma.core.render import canvas from luma.oled.device import ssd1306, ssd1309, ssd1325, ssd1331, sh1106, ws0010 # rev.1 users set port=0 # substitute spi(device=0, port=0) below if using that interface # substitute parallel(RS=7, E=8, PINS=[25,24,23,27]) below if using that interface serial = i2c(port=1, address=0x3C) # substitute ssd1331(...) or sh1106(...) below if using that device device = ssd1306(serial)
The display device should now be configured for use.
The device classes all expose a
display() method which takes an image with
attributes consistent with the capabilities of the device. However, for most
cases when drawing text and graphics primitives, the canvas class should be used
with canvas(device) as draw: draw.rectangle(device.bounding_box, outline="white", fill="black") draw.text((30, 40), "Hello World", fill="white")
luma.core.render.canvas class automatically creates an
object of the correct dimensions and bit depth suitable for the device, so you
may then call the usual Pillow methods to draw onto the canvas.
As soon as the with scope is ended, the resultant image is automatically
flushed to the device’s display memory and the
PIL.ImageDraw object is
When a program ends, the display is automatically cleared. This means that a fast program that ends quickly may never display a visible image.
Any of the standard
PIL.ImageColor color formats may be used, but since
the SSD1306, SH1106 and WS0010 OLEDs are monochrome, only the HTML color names
"white" values should really be used; in fact, by default,
any value other than black is treated as white. The
object does have a
dither flag which if set to
True, will convert color drawings
to a dithered monochrome effect (see the 3d_box.py example, below).
with canvas(device, dither=True) as draw: draw.rectangle((10, 10, 30, 30), outline="white", fill="red")
There is no such constraint on the SSD1331 or SSD1351 OLEDs, which features 16-bit RGB colors: 24-bit RGB images are downsized to 16-bit using a 565 scheme.
The SSD1322, SSD1325 and SSD1362 OLEDs all support 16 greyscale graduations: 24-bit RGB images are downsized to 4-bit using a Luma conversion which is approximately calculated as follows:
Y' = 0.299 R' + 0.587 G' + 0.114 B'
Landscape / Portrait Orientation¶
By default the display will be oriented in landscape mode (128x64 pixels for
the SSD1306, for example). Should you have an application that requires the
display to be mounted in a portrait aspect, then add a
when creating the device:
from luma.core.interface.serial import i2c from luma.core.render import canvas from luma.oled.device import ssd1306, ssd1325, ssd1331, sh1106 from time import sleep serial = i2c(port=1, address=0x3C) device = ssd1306(serial, rotate=1) # Box and text rendered in portrait mode with canvas(device) as draw: draw.rectangle(device.bounding_box, outline="white", fill="black") draw.text((10, 40), "Hello World", fill="white") sleep(10)
N should be a value of 0, 1, 2 or 3 only, where 0 is no rotation, 1 is rotate 90° clockwise, 2 is 180° rotation and 3 represents 270° rotation.
device.height properties reflect
the rotated dimensions rather than the physical dimensions.