The screen

128×64, one bit per pixel.

with eilik.connect() as robot:
    robot.screen.show("face.png")     # scaled, thresholded, rotated for you
    saved = robot.screen.read()       # 1024 bytes, the panel's own order
    robot.screen.clear()

Images versus framebuffers

show takes either a path or a Pillow image, or a ready 1024-byte framebuffer. The difference is deliberate: an image is converted here, including the 180 degree rotation the panel needs, while a framebuffer is already in the panel’s order and goes out untouched. Rotating it again would undo work you had already done.

Drawing without Pillow

pack and unpack in eilik.screen convert between framebuffers and a 64×128 grid of 0/1 with no dependencies at all.

Layout

The panel is SSD1306 page mode: 8 pages of 128 columns, and within a byte the least significant bit is the top row of its page. Pixel (x, y) is bit y % 8 of byte (y // 8) * 128 + x.

The panel is mounted rotated 180 degrees relative to that byte order, so a buffer written as-is appears upside down.