Ever played with magic slates in your childhood? Well this project will show you how to make a digital magic slate using a PC, a touch screen and few other components. Basically the project converts the analog voltage coming from the resistive touch screen into a two co-ordinate integer value and sends it to the PC through the microcontroller. The processing code takes these co-ordinates as inputs and draws a white dot for each co-ordinate, on the output screen.
So when you write continuously on the touch screen, the dots would be plotted close enough to make it look like a line or curve. The circuit is based around a Atmega 16 micro controller, Serial to USB converter or (Serial to RS-232 + RS-232 to USB converter) along with a personal computer or a laptop.