Make LED glow by powering a PI:

An experiment to get on with the electric circuits.

Components Required:

  1. Raspberry PI
  2. LED
  3. Jumping wires
  4. Resistors
  5. Ribbon cable
  6. Breadboard

Firstly, to power up LED we need to know the maximum voltage that can be handled by LED. In order to reduce the current flow, we need to add a resistor onto the circuit. In my experiment, I used two 200 ohms resistors that are connected in series i.e. 400 ohms on the whole.

Secondly, connect the anode of the LED to the positive terminal i.e. 5V pin and the cathode to a resistor. The other end of the resistor to the ground pin of the PI.

Circuit after connection


Finally, after setting up the connections switch on the PI and this will turn on the LED as well.

Image after power supply


Connect laptop and PI using TTL:

In order to establish the connection, we need to install a driver i.e. USB to TTL in the PC and in the PI we need to enable TTL connection.

In PI open the terminal and type “sudo nano config.txt”


then a file will be open and navigate to the end of the file


In the last line write “enable_uart=1” and this statement enables the serial connection from laptop or PC.img_1417

Now coming to connections, TTL receiver must be connected to PI transmitter pin and TTL transmitter pin is connected to PI receiver pin. In additional to above, a power source can be supplied from the same TTL device by connecting ground and either of the voltage pins to the respective pins of the PI.

Image after connection


Connect laptop and PI using Ethernet or the Internet:

In order to get a display of the PI on a laptop, we need to install VNC server in the PI and enable screen sharing option. While installing it is necessary to enter a key or a password, which is necessary for logging in the PC you want to get the display. In the PC we need to install VNC viewer software and this software is necessary to read the data from the PI. After connecting PI to the network, our main intention is to know the IP address of the PI. After knowing the IP address of PI, we need to enter that IP address in the VNC viewer. The viewer will prompt to enter the password of the PI.

Stuff required to do this?

  1. Raspberry Pi.
  2. Ethernet Cable.
  3. Laptop
  4. SD Card with Raspbian.


Observe the references in order to follow above procedure:


USB to TTL drivers: USB – TTL Drivers

USB to TTL work on PI: Things to be done in PI terminal

Laptop to PI using network: Raspberry PI to laptop using Ethernet cable