In this tutorial, I am going to show a I/O expander method using PCF8574A, which is a 8 bit I/O expander using I2C bus. This is another alternative other than using shift registers to expand either inputs or outputs such as 74HC595 (outputs) or 74HC165 (inputs). One of the advantages of using PCF8574A I/O expander is that it uses I2C bus, which requires only two data lines, they are clock (SCK) and data (SDA). Therefore, with these two lines, you can control up to eight of the same chip by changing the address input, providing extra 64 I/O pins.
Today, I am going to share on how you can make a low voltage audio amplifier. For this project, I am using LM 386 Audio Amplifier, which is commonly used among electronics hobbyist. I will break the article into a few sections. First, I will explain about the LM 386 chip itself. Then move on with some explanation on the parts used in this project. And finally, the design of audio amplifier.
During my third year studying electronics engineering, I have made a wall following robot for the course EEE 351 Advanced Laboratory. This mini project is done in a team of four. For this project, we are required to apply control system theory into application, which lead us into making the wall following robot. As the name sounds, the robot’s main objective is to follow the wall within a target distance. In order to maintain certain distance from the wall, this is where we applied a digital controller, which is the PID controller. PID controller stands for Proportional, Integral and Derivative Controller which is used to calculate the error between the measured and desired set point and attempts to minimize the error. For more information about PID controller, have a look at Wiki. Continue reading “Wall Following Robot”
Previously, I’ve made a tutorial on how to use a 74HC595 Serial In/ Parallel Out Shift Register, which is useful in expanding output pins. In this tutorial, I am going to show another shift register which is capable of expanding input pins. The IC that I am using is 74HC165 Parallel In/ Serial Out Shift Register. One of the advantages that need to be stressed on is that by using only four pins, I can get eight input pins. Moreover, it can be cascaded, thus you can have any amount of input pins with only four pins with the help of this shift register. Continue reading “74HC165 8 bit Parallel in/Serial out Shift Register”
I had think of making a game on Arduino quite a while. An idea strikes to my mind while I was playing a quite popular game which is available on apps and pc, 2048. 2048 is actually a game created by Gabriele Cirulli, aged 19, Itallian web developer. The objective of this game is to slide the tiles and combine them to create the tile of 2048. Source: Wiki
Previously I have made a colour sensor using Arduino but don’t have the time to update it on my blog. Today I am going to share the details of this mini project. Basically, the sensor consists of three LEDs and Light Dependent Resistor (LDR). The LDR will detect the colour and display it to another RGB LED. Besides display it on the RGB LED, the colour will also display on PC. RGB LED is commonly used in display colours on LCD or OLED such as the monitor and television. Continue reading “Colour Sensor”
While I was free during my holiday, I decided to make a simple Arduino Piano playing musical notes. Playing musical notes is quite simple with the Arduino built in function Tone(). Overall this project’s difficulty should be easy. Another reason I wanted to make this mini project, is to make a piano with 12 keys, but using lesser amount of pins. Continue reading “Arduino Piano”
I was always fascinated with LED Matrix Display because it makes a good and clear display. I always saw LED display used as advertisement signboard. It can be programmed with variety of animations. So I decided to make myself a 48×8 LED Matrix Display. Of course, I start off with a smaller one by soldering LEDs on stripboard, making a 8×8 LED Matrix. I tried to understand how the LED Matrix works and how to deal with the programming part. Continue reading “Development of 48×8 Led Matrix Display”
I often use Arduino to test out my project prototype before complete it. Sometimes, I wanted to test more than one project at the same time. I would need more Arduino, but the original Arduino is over my budget for prototyping purpose. Therefore, I decided to make my own Arduino. Some of the benefits of making your Arduino (at least for me) are it is cheap, easy, learn to design PCB and electronics at the same time. Although there are a lot of guides on how to make your own Arduino, I decided to make one so as I can share with my readers, and at the same time document it for myself. Continue reading “Build your own Arduino Uno”