Requirements

  • Raspberry Pi running Raspbian Jessie with display, mouse, keyboard and power source (see Introduction, steps 1-5)
  • Breadboard
  • LED
  • Resistor (50-100 Ohm is good for most LEDs – ask your vendor for a LED + resistor for 3.3V and 20mA )
  • 2 Male-To-Female jumper cables

Raspberry Pi electronics interface GPIO
Before basic circuitery, lets have a look at the General Purpose Input Output interface (GPIO) of the Raspberry Pi. The GPIO is where sensors, motors, lights and so on are attached. It has 40 pin connectors and looks like this:

Raspberry Pi General Purpose Input Output

Raspberry Pi General Purpose Input Output

There are different ways for enumerating the connectors. The BOARD enumeration used on this site simply counts the pins,
starting with the bottom left pin as pin 1, top left as pin 2, bottom secondmost left as pin 3 and so on. Typing
gpio readall
in the terminal displays all enumeration types and the function of each pin in a comfy table:
GPIO table

GPIO table

Breadboard
Before soldering a circuit together, it is usually tested on a breadboard like this one:

Breadboard

Breadboard

The top two and bottom two lines are used for the power supply. They are horizontally conductive, but not vertically, and are used for splitting the Voltage in and Ground for as many components of the circuit as required. The middle block is conductive vertically, but not horizontally, and is used to build the test circuit. The middle line breaks the vertical conductivity for giving more options for the circuit.

Sample circuit
Now, build the sample circuit, with pin 1 (3.3V) connected to the positive pole of the LED over the resistor and pin 6 (ground) connected to the negative pole:

Sample Circuit

Sample Circuit

Make sure the LED is oriented like in the picture! Now, power up the Raspberry Pi- the LED glows instantly.
Many Raspberry Pi tutorials and projects supply breadboard circuits; others use circuit schematics, which are more difficult to read.

Fritzing for drawing circuits
The sample circuit was created with the great freeware circuit drawer Fritzing. It is easy to install and use, allows not only drawing breadboard circuits, but also conversion to schematics and and formats for circuit printers. If you like it, please support the Fritzing project by donating!

Comment

Time limit is exhausted. Please reload CAPTCHA.