114 lines
2.9 KiB
Markdown
114 lines
2.9 KiB
Markdown
# Plasma <!-- omit in toc -->
|
|
|
|
The Plasma library is intended to drive APA102 / DotStar™ or WS2812 / NeoPixel™ LEDs on the Plasma 2040 board, though it can be used with your own custom pins/wiring.
|
|
|
|
- [Notes On PIO Limitations](#notes-on-pio-limitations)
|
|
- [APA102](#apa102)
|
|
- [Getting Started](#getting-started)
|
|
- [Set An LED](#set-an-led)
|
|
- [RGB](#rgb)
|
|
- [HSV](#hsv)
|
|
- [Set Brightness](#set-brightness)
|
|
- [WS2812](#ws2812)
|
|
- [Getting Started](#getting-started-1)
|
|
- [Set An LED](#set-an-led-1)
|
|
- [RGB](#rgb-1)
|
|
- [HSV](#hsv-1)
|
|
|
|
## Notes On PIO Limitations
|
|
|
|
The WS2812 and APA102 drivers use the PIO hardware on the RP2040. There are only two PIOs with four state machines each, placing a hard limit on how many separate LED strips you can drive.
|
|
|
|
In most cases you'll use `0` for PIO and `0` for PIO state-machine, but you should change these if you plan on running different strand types together, or if you're using something else that uses PIO.
|
|
|
|
## APA102
|
|
|
|
### Getting Started
|
|
|
|
Construct a new `WS2812` instance, specifying the number of LEDs, PIO, PIO state-machine and GPIO pin.
|
|
|
|
```python
|
|
import plasma
|
|
|
|
LEDS = 30
|
|
FPS = 60
|
|
|
|
led_strip = plasma.WS2812(LEDS, 0, 0, 15)
|
|
```
|
|
|
|
Start the LED strip by calling `start`. This sets up a timer which tells the RP2040 to DMA the pixel data into the PIO (a fast, asyncronous memory->peripheral copy) at the specified framerate.
|
|
|
|
```python
|
|
led_strip.start(FPS)
|
|
```
|
|
|
|
### Set An LED
|
|
|
|
You can set the colour of an LED in either the RGB colourspace, or HSV (Hue, Saturation, Value). HSV is useful for creating rainbow patterns.
|
|
|
|
#### RGB
|
|
|
|
Set the first LED - `0` - to Purple `255, 0, 255`:
|
|
|
|
```python
|
|
led_strip.set_led(0, 255, 0, 255)
|
|
```
|
|
|
|
#### HSV
|
|
|
|
Set the first LED - `0` - to Red `0.0`:
|
|
|
|
```python
|
|
led_strip.set_hsv(0, 0.0, 1.0, 1.0)
|
|
```
|
|
|
|
### Set Brightness
|
|
|
|
APA102 pixels support global brightness, allowing their brightness to be specified independent of their colour. You can set the overall brightness of your strip by calling:
|
|
|
|
```python
|
|
led_strip.set_brightness(15)
|
|
```
|
|
|
|
You can set brightness from `0` to `31`. This directly maps to the 5-bit brightness value sent to the APA102 LEDs.
|
|
|
|
## WS2812
|
|
|
|
### Getting Started
|
|
|
|
Construct a new `APA102` instance, specifying the number of LEDs, PIO, PIO state-machine and GPIO data/clock pins.
|
|
|
|
```python
|
|
import plasma
|
|
|
|
LEDS = 30
|
|
FPS = 60
|
|
|
|
led_strip = plasma.APA102(LEDS, 0, 0, 15, 14)
|
|
```
|
|
|
|
Start the LED strip by calling `start`. This sets up a timer which tells the RP2040 to DMA the pixel data into the PIO (a fast, asyncronous memory->peripheral copy) at the specified framerate.
|
|
|
|
```python
|
|
led_strip.start(FPS)
|
|
```
|
|
|
|
### Set An LED
|
|
|
|
You can set the colour of an LED in either the RGB colourspace, or HSV (Hue, Saturation, Value). HSV is useful for creating rainbow patterns.
|
|
|
|
#### RGB
|
|
|
|
Set the first LED - `0` - to Purple `255, 0, 255`:
|
|
|
|
```python
|
|
led_strip.set_led(0, 255, 0, 255)
|
|
```
|
|
|
|
#### HSV
|
|
|
|
Set the first LED - `0` - to Red `0.0`:
|
|
|
|
```python
|
|
led_strip.set_hsv(0, 0.0, 1.0, 1.0)
|
|
``` |