Anyone here who love to deal with mathematical solutions, please rise up your hand! Well, for those who have no interest in the mathematics, calculating could be a horrible nightmare to you.
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:
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.