View source for BakeBit - Green LED

[[BakeBit - Green LED/zh|查看中文]]

==Introduction==
[[File:BakeBit - Green LED.jpg|thumb|Green LED]]
* The BakeBit - Green LED is an LED module. This module has a a triode which is used to turn the LED on or off. There is a potentiometer in series connection with the LED. When users adjust the potentiometer the LED's luminance will be changed accordingly.Or you input PWM signals to control the the LED's luminance.

==Hardware Spec==
* Standard 2.0mm 4-Pin BakeBit Interface
* LED's luminance adjustable
* Digital Input
[[File:BakeBit Green LED PCB.png | frameless|300px|BakeBit - Green LED]]

* Pin Description:
{| class="wikitable"
|-
|Pin || Description
|-
|GND   || Ground
|-
|5V    || 5V Supply Voltage
|-
|NC    || Not Connected
|-
|SIG   || Signal
|}

== Code Sample:LED Blink ==

=== Hardware Connection ===
连接LED到NanoHUB扩展板的D3接口：

::{| class="wikitable"
|-
|[[File:LED-1.jpg |frameless|300px]]    || [[File:LED-2.jpg |frameless|300px]] 
|-
|}

=== Source Code ===

<syntaxhighlight lang="python">
import time
from bakebit import *

# Connect the BakeBit LED to digital port D3
led = 3

pinMode(led,"OUTPUT")
time.sleep(1)

print ("This example will blink a BakeBit LED connected to the BakeBit on the port labeled D3.\nIf you're having trouble seeing the LED blink, be sure to check the LED connection and the port number.\nYou may also try reversing the direction of the LED on the sensor.")
print (" ")
print ("Connect the LED to the port labele D3!" )

while True:
    try:
        #Blink the LED
        digitalWrite(led,1)		# Send HIGH to switch on LED
        print ("LED ON!")
        time.sleep(1)

        digitalWrite(led,0)		# Send LOW to switch off LED
        print ("LED OFF!")
        time.sleep(1)

    except KeyboardInterrupt:	# Turn LED off before stopping
        digitalWrite(led,0)
        break
    except IOError:				# Print "Error" if communication error encountered
        print ("Error")
</syntaxhighlight>

[https://github.com/friendlyarm/BakeBit/blob/master/Software/Python/bakebit_led_blink.py Github]

=== Run Code Sample ===

Before you run the code sample you need to follow the steps in [http://wiki.friendlyarm.com/bakebit bakebit tutorial] to install the BakeBit package.<br />
Enter the "BakeBit/Software/Python" directory and run the "bakebit_led_blink.py" program:
<syntaxhighlight lang="bash">
cd ~/BakeBit/Software/Python
sudo python bakebit_led_blink.py
</syntaxhighlight>

=== Observation ===

The BakeBit LED keeps blinking and the interval between two blinks is one second.

==Resources==
*[Schematic]([http://wiki.friendlyarm.com/wiki/images/2/2e/08-SCHEMATIC_LED.pdf BakeBit - Green LED.pdf])
*[BakeBit Github Project Page](https://github.com/friendlyarm/BakeBit)
*[BakeBit Starter Kit User's Manual](http://wiki.friendlyarm.com/bakebit/bakebit_starter_kit_manual_en.pdf)

==Update Log==
===Dec-14-2016===
* Released English version