STM32F4Discovery board is already quite powerful and stacked with many handy features. On a single board, you can find a three-axis accelerometer, MEMS microphone, DAC with D class amplifier that can output sound through the built-in audio jack. Also, there are a couple of LEDs and a button for fast access. And of course, the core of this board is STM32F407VGT6 ARM Cortex-M4 microcontroller that packs series of great features including DSP instructions and floating point unit. But eventually, with such power, you will miss several other handy features that could be used in your project. Think of LCD, Ethernet, RS232 interface and even camera. You could start making your extension boards that include additional features, but why bother, since there already are several extension boards available for it. Let us go through them and see the features you could get without a heating soldering iron.
You’ve probably noticed that day by day more complex hardware gets closer to a user. Of course, I am talking about microcontrollers and processors. Several years ago it was a challenge to have running Linux on board. Now almost everyone has Raspberry Pi and doing crazy things. As I have noticed not many hobbyists are building their boards to get things done. There is a wide variety of ready made developing boards depending on size, speed, price that it looks not worth spending time on what’s already done. Everyone seems to be grabbing Arduino and building amazing projects. In a couple of years, enthusiasts used to crunch ARM projects like cookies. This is thanks to the choice of cheap development boards and improving free software tools. But the most critical role in this is the manufacturers. They finally noticed that hobby market could be a powerful driving mechanism. Ignoring it means losing the game. Now almost every hardware company is trying to get their development board closer to maker and hacker community. Because they like to build stuff and spread the word about it.