RGB LED
Revision as of 22:47, 19 August 2020 by Skwhadmin (talk | contribs) (→A small Program in MicroPython)
Contents
Description
A regular RGB LED is basically 3 LEDs (one red, one green, one blue) in parallel. This is not a smart LED, for smart LEDs see LED Ring NeoPixel.
How to connect it electrically
The RGB LED is connected like 3 paralell LEDs. It is important that you need one resistor for each color! The resistor goes before the LED and not onto the common ground.
How to control it in MicroPython
1 # todo
2 # code goes here
A small Program in MicroPython
1 from machine import Pin, PWM
2 from time import sleep
3
4 # connect it to Pin 26, 27, and 14
5 blue = PWM(Pin(26))
6 green = PWM(Pin(27))
7 red = PWM(Pin(14))
8
9 # base frequency for PWM is 1000Hz
10 blue.freq(1000)
11 green.freq(1000)
12 red.freq(1000)
13
14 # this is a function to allows to give an "RGB"-Color to the LED
15 # duty take an argument from 0 to 2023... by multiplying the 0..255 by 4 we get 0 to 2020 - which seems close enough
16 def rgb(r=255,g=255,b=255):
17 blue.duty(b*4) # set duty cycle
18 green.duty(g*4) # set duty cycle
19 red.duty(r*4) # set duty cycle
20
21 # show some cases....
22 while True:
23 rgb(255,255,255) # white
24 sleep(1)
25 rgb(0,0,0) # off = black
26 sleep(1)
27 rgb(255,0,0) # red
28 sleep(1)
29 rgb(0,255,0) # gree
30 sleep(1)
31 rgb(0,0,255) # blue
32 sleep(1)
Related Tutorial Videos
In this part of the tutorial, we show how to connect an RGB-LED and programming it with Micropython. We first look at what an RGB LED is by building one with 3 separate LEDs. We then look at switching it on and off and how to set the color using the duty cycle in the PWM output.
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