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scripts | ||
colours.js | ||
LICENSE | ||
neopix | ||
neopix.py | ||
neopixel.html | ||
neopixel.js | ||
package.json | ||
README.md |
node-red-node-pi-neopixel
A Node-RED node to drive a strip of Neopixel or WS2812 LEDs from a Raspberry Pi.
Pre-requisites
The Neopixel python driver need to be pre-installed... The easiest way to get the driver installed is to use the Unicorn HAT drivers install script... see the Pimoroni Getting Started with Unicorn HAT page.
curl -sS get.pimoroni.com/unicornhat | bash
Install
Run the following command in your Node-RED user directory - typically ~/.node-red
npm install node-red-node-pi-neopixel
The data pin of the pixels should be connected to physical pin 12 - GPIO 18 of the Pi. Note: this may conflict with audio playback.
Usage
To set the background just set msg.payload
to an html_colour
name.
Here
is a list of html_colour names.
It also accepts a string triple rrr,ggg,bbb
or #rrggbb
#### Bar Chart
Defaults style mode using configured foreground and background colours. The foreground colour is used to indicate the number of pixels or length required.
It accepts a number in msg.payload
that can be either the number of pixels,
or a percentage of the total length.
If you want to change the foreground colour, you can set msg.payload
to a
comma separated string of html_colour,length
or length,html_colour
. The
foreground will then remain that colour until changed again.
Needle
It can also display a needle (single pixel) type gauge. The rest of the pixels are set to the background colour on one side, and the foreground colour on the other side of the indicated pixel.
If you want to change the needle colour, you can set msg.payload
to a
comma separated string of html_colour,length
or length,html_colour
.
Shift left and Shift right
You can also select shift modes where a single colour pixel is added to either
the start or the end of the strip, shifting all the others along by one. In this
mode the msg.payload
can be specified as either an html colour name, an r,g,b triple or #rrggbb.
Low level "API"
The nth
pixel of the string can be set by msg.payload
with a CSV string n,r,g,b
,
where r, g and b are 0-255.
A range of pixels from position x
to y
can be set by msg.payload
with a CSV string x,y,r,g,b