After we've turned on the diode by connecting it to the batteries it is time to do the same thing, but with a diode connected to the Raspberry Pi. So it will be the Raspberry Pi that is controlling when and how is the diode turned on. Because of the Disk Image that we've burned on the SD card we would have the diode blinking when the operating system is turned on.
- 13 Feb 2018
Connect a resistor to the diode. Connect system to pin 12 and pin 14. After turning on, wait for 10-15 seconds and the diode will blink.
Use of a resistor
We would have to introduce you to the electronic element - resistor. It's not the hero we want. It's the hero we need. When we connect the diode to the controller the current that would flow through the diode will burn it. We must put something that would reduce the amount of current that is allowed to flow in the system. The special element that does exactly this is a resistor. There is a lot we should mention about voltages here, but let's just leave it like this. If you want to learn more try to search on the internet for an answer to the following question: "is it the amount of current or voltage that burns the diode".
In the picture below the resistor is connected with cables to the diode
Connect to the Raspberry PI
On the picture, the white cable is attached to the longer pin of the diode. The black and white cable is attached to the shorter pin. The white cable is attached to a resistor which is then attached to a blue cable. Connect the cables in the following way to the Raspberry Pi. Blue cable to pin 12. Black and white cable to pin 14. Because you don't know the number of the pins yet, just look at the picture.
Now when you start the Raspberry Pi after a few second the diode should blink. This is an indication that the system has started and that the Raspberry PI has loaded the operating system Ubuntu Mate and is now ready to accept other instructions and execute programs.
Courses and lessons with this Tutorial
This Tutorial is used in the following courses and lessons