Mounting up of LED directly on the board helps in reducing the cost when done on large scale. Onboard LED's also looks good when placed on a small board. On Arduino there are 4 onboard LED's which helps in giving status to the user. In the image below you can observe where these LED's are located on Arduino.
Click here to Check Specs Of Arduino Uno
Click here to Check Specs Of Arduino Uno
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| LED's position on Arduino Uno |
Name and Function Of these LED's
So there are 4 LED on Arduino of different color from which 3 are located nearby and one is little far away. Lets Look and Study each Led
1. Power LED (Green)
It is a basic LED which power ON when the device is connected to a power supply (USB or Adapter). It is green in color and shows that arduino is powered ON.
2. Status LED (Orange)
It is a built-in LED connected to digital pin 13. When the pin is HIGH value, the LED is on, when the pin is LOW, it's off. It is Orange in color. It is also used to make basic LED blinking Example.
3. Serial Communication LED's (Orange)
Serial communication LED's are basically communication LED which are powered on when the board sends or receives any data from computer through USB cable.
- TX : When arduino sends data to PC ( eg. sending information )
- RX : When arduino receives data from PC ( eg. downloading program )
Normally there are only 4 LED on Arduino Uno R3 but it may vary depending on the version of the board. The arduino like boards may have a normal 3mm LED placed on them. These onboard LED are very important for a user as he can see the status of his board and what is happening at a particular instance of time.
