HPK taruh disini
LED or Light Emitting Diodes is a two-lead semiconductor light source. It is a pn-junction diode, which emits light when activated. When a suitable voltage is applied to the leads, electrons are able to recombine with electron holes within the device, releasing energy in the form of photons. This effect is called electroluminescence, and the color of the light (corresponding to the energy of the photon) is determined by the energy band gap of the semiconductor. An LED is often small in area (less than 1 mm2) and integrated optical components may be used to shape its radiation patterns.
LED comes as small amazing thing that produce light by conduct itself. It comes in many different colors. People usually uses it as indicator light or as replacement of lamp because of the low power consumption, long lifetime, improved physical robustness, small size, and fast switching.
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| LEDs (Light Emitting Diodes) |
Arduino Uno is a microcontroller board based on the ATmega328. It has 14 digital input/output pins (of which 6 can be used as PWM outputs), 6 analog inputs, a 16 MHz ceramic resonator, a USB connection, a power jack, an ICSP header, and a reset button. It contains everything needed to support the microcontroller; simply connect it to a computer with a USB cable or power it with a AC-to-DC adapter or battery to get started. The Arduino Uno can be powered via the USB connection or with an external power supply. The power source is selected automatically.
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| Arduino Uno |
MRT or Mass Rapid Train is a rapid transit system forming the major component of the railway system. Every station is equipped with General Ticketing Machines (GTMs), a Passenger Service Centre, LED and plasma displays that show train service information and announcement.
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| An SMRT Active Route Map Information System that showing the current location of a train and upcoming stops |
In this Microprocessor Course, we will try to make a little project by this amazing LED with Arduino Uno. This prototype project called "Simple LED for Location Notification Panel in MRT”.
Let's see what we need here!
First, make sure you have a board of microcontroller (such as Arduino Uno) or simply make it in simulation by using Proteus.
Second, prepare Printed Board Circuit (PCB), 8 pieces of LED, 8 pieces of 330 ohm resistor and male connector or install Proteus here and download Arduino library in Proteus here.
Third, design hardware as below:
1. Using Proteus for Simulation
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| Using Proteus for Simulation |
2. Make the real hardware
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| Front View |
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| Back View |
By making the real hardware, you have two choice for connecting the LED, whether Common Anode or Common Cathode.
- Common Anode LEDs should have connected all anode leg of each LED and connected to the 5V pin on your Arduino (Current sink).
- Common Cathode LEDs should have connected all cathode leg of each LED and connected to the ground pin on your Arduino (Current source).
While making the hardware, make sure your hardware match the microcontroller board. Hardware is designed in a circle model, so the light will run in a round from location A to H and back to the point A. The light will blink for the upcoming stops and will turn on in the current and passed location.
Fourth, design software for both simulation and real hardware, by using Arduino Software as below (time delay can be set according to the needs):
Last, upload your software and run your project!
Simulation on Proteus
Simulation on Arduino
