MicroPython DotStar

Higher level DotStar driver that presents the strip as a sequence. This is a port of the Adafruit CircuitPython DotStar library. The primary change is to require an SPI object to be configured before creating the DotStar object. SPI communciations are used to control the DotStars.

Note

Be aware that SPI can be implemented using hardware support or purely in software. Hardware implementations allow higher rates of transmission and can be desirable particularly for long strips of DotStars. SPI implementation is port-dependent so see your port-specific documentation for details.

Colors are stored as tuples by default. However, you can also use int hex syntax to set values similar to colors on the web. For example, 0x100000 (#100000 on the web) is equivalent to (0x10, 0, 0).

If you send a tuple with 4 values, you can control the brightness value, which appears in DotStar but not NeoPixels. It should be a float. For example, (0xFF,0,0, 1.0) is the brightest red possible, (1,0,0,0.01) is the dimmest red possible.

Note

The int hex API represents the brightness of the white pixel when present by setting the RGB channels to identical values. For example, full white is 0xffffff but is actually (0xff, 0xff, 0xff) in the tuple syntax.

Note

DotStar refers to an Adafruit product based on an electronic part known as APA102. 'Dotstar' and 'APA102' can be used interchangeably.

Usage Example

This example demonstrates the library with a single DotStar connected to Pins 12 and 13. This matches the configuration of the TinyPICO. On this platform (ESP32-based) this is using software SPI.

from micropython_dotstar import DotStar
from machine import SPI, Pin

spi = SPI(sck=Pin(12), mosi=Pin(13), miso=Pin(18)) # Configure SPI - see note below
dotstar = DotStar(spi, 1) # Just one DotStar
dotstar[0] = (128, 0, 0) # Red
dotstar[0] = (128, 0, 0, 0.5) # Red, half brightness
dotstar.fill((0,0,128)) # Blue

Note

'miso=Pin(18)' is only required due to a quirk in the current software SPI implementation where all of sck, mosi and miso must be set. It's expected that this limitation will be lifted in the future. In this example Pin(18) is simply unused since DotStars don't send data back to the master.

Raspberry Pi Pico Example

This example demonstrates the library with a single DotStar connected to SCK Pin 10 and Tx Pin 11 on the Raspberry Pi Pico.

from micropython_dotstar import DotStar
from machine import SPI

spi = SPI(id=1, sck=10, mosi=11) # Configure SPI
dotstar = DotStar(spi, 1)        # Setup one DotStar

dotstar[0] = (128, 0, 0)         # Red
dotstar[0] = (128, 0, 0, 0.5)    # Red, half brightness
dotstar.fill((0,0,128))          # Blue