In the previous tutorials, I have shown how to use the simple GPIO and external interrupt of the STM32. Since these peripherals are connected with external pins, we can visually observe how it works through some LEDs of the Discovery kit. Therefore, it is very easy to know whether our code is working correctly or not. However, when you are playing with some kinds of internal peripherals such as Timer/Counter, UART,… with types of data are not bit anymore but byte or integer or float, you will need something else to diagnose that data. Typically, the programming environment like Keil or IAR provides us a debugging tool to debug those kinds of data in real time but I found they are not so convenient and user-friendly at all. So, to prepare for our next tutorials, which will be more about internal peripherals, I am going to introduce you to the STM Studio from STMicroelectronics.