According to the history of calculator, the abacus was the very first arithmetic invention used by ancient merchants in Asia and Africa. Believe it or not, the abacus is still being used by many people, especially in China!

The World’s first all-electric compact calculator is the Model 14-A calculator, which is a proud product from The Casio Computer Company, Japan in 1957. Four years after that, the world’s first all-electronic desktop calculator, the Bell Punch/Sumlock Comptometer ANITA was announced.

Later on, the designation of calculator is becoming more advanced, where its applied the nickel-cadmium batteries and liquid crystal displays onto the modern calculators. Yet, majority of the calculators in present days are equipped with tiny solar panel on the top left corner!

Let’s go back to the topic again. The talking calculator is a user-friendly calculator. It based on an ATmega88 microcontroller. It features the four basic operations:

• Addition,

• Subtraction,

• Multiplication, and

• Division.

Beside that, it includes with several useful functions, such as the change of sign (+/-), inverse (1/x), add with memory (M+) and read from memory (MR).

The talking calculator uses the speech waveform encoder RC-2. Hence, it needs two resistors and one capacitor to do the voice decoding stuff. While, the LM4861, an Audio Power Amplifier with the incredible Shutdown Mode feature, is being applied to the talking calculator to amplify the sound.

Furthermore, things start to out of control, if you are handling a pool table that has four adjustable feet, which you can fiddling around with the spanner and trying to figure out what is the exact table level is! Yeah, the whole scene could turn into a really nasty and huge pain for the fixer…

However, there’s better solution for the above matter. Let’s meet the Mr. Incredible, Dual-Axis Level Sensor (Oops, is it really a person?).

Basically, the dual-axis level sensor is based on LPC2138 microcontroller. Even though the designation is quite simple and unattractive, but it provides exceptional convenience to the users!

For your information, the sensor system is fully-designed around electrolytic tilt sensors, where is capable of providing precise positioning measurements in within a few seconds!

The units form the basis for many other applications. The Dual-axis level sensor is including with self-leveling platform, builder level, pinball, pool table leveling and other industrial applications. Hence, it’s suitable for being used, not only at home but in the industry sectors as well!

At that moment, you really don’t want to open up the car’s door and walking to the outside in below zero Celsius degree to check up your fuel oil gauge. However, you have no choice, but still have to do it in the ultimately freezing environment. Ok, you’re discovered that your vehicle was running out of fuel. So, you rush to the nearest fuel station to buy a few gallon of fuel. Once you’re checking your wallet. Darn, it’s already empty…!

Honestly, it’s one of the most annoying yet torturing scene, and some of us might have been encountered with this kind of situation before. Well, for preventing the awkward moment happen on you, then it’s better to well-prepared, by developing a smart Arduinoil device!

The main purpose of Arduinoil is allowing you to read the information from your vehicle’s current oil gauge and feed it to a web-enabled service. As a result, you not only can check the current fuel level, but also have latest stats available from everywhere across the worldwide.

In most of the case, the typical uses of audio card are including:

• Music composition,

• Editing video or audio,

• Presentation with audio effect,

• Education, and

• Entertainment.

Normally, audio card is referred as a digital-to-analog converter (DAC). It has the ability to convert record digital data into an analog format. The output signal is connected to an amplifier, headphones or external device using standard interconnects.

However, the only downfall of the general audio card is it becomes a hassle to add new PCI audio device to a PC. In this case, the USB Audio Card project is the best choice to overcome the disadvantage of the general audio cards!

The project is based on a high-speed USB and a powerful ATmega162L-8PI microcontroller. The incredible USB B-type-to-A-type cable is the most amazing cable for this USB audio card. By using this cable, it allows you to connect the audio card to the PC with only a simple switch!

Also, you can listen to MP3 and WAV files with the USB audio card, by simply connecting the earphone to the card!

In this case, this cheapest dual trace scope would be the best example. Different from the other dual trace scope, it’s a submini USB scope that based on an Atmel Tiny45 CPU.

Basically, it has two analog inputs and can supply 5V onto the 4 pins header on the right. For your information, one of the inputs can be easily scaled down with the trim pot.

Furthermore, the firmware in the Tiny45 is well-written in C language and compiled with Winavr and USB source code from obdev.

If you’re referring to the above figure, you might find out that there is no crystal, as the software sync the internal 16.5MHz PII clock with the USB clock!

The device is designed to plug into a project breadboard. In this case, there is no need for you to apply a power supply on it. The dual trace scope can be connected directly to a PC with USB in HID mode, without needing to install any specific driver.