Abstract:  In order to generate the real random numbers, which can be applied to the practice, this paper proposes a new method of using microcontroller timer to generate random numbers. It uses microcontroller timer to test button press time, using the time interval of the button when it is on to calculate the randomness of the random number. When the button pressed, microcontroller reads the value of the timer immediately, this value is the random Numbers. The experimental results showed that the probability density distribution is uniform and its the correlation is close to zero, and this method is more simple than pure mathematics physics method.

Key words: generation of random numbers,  random number, validation of the random number