Introduction

Things are getting interesting: no more blinky LEDs from sysfs. It's real time...time to learn about how to make your BeagleBone Black perform real-time tricks.

This is not to say that the BeagleBone Black is pokey. The challenge is that, nowadays, innovators, developers, product designers, and engineers always demand faster, more predictable results, especially in scenarios where small latencies can make the difference between success or crash. Crash in this case meaning bang, crash goes the device, not just a software crash.

So, in this chapter, we will examine recipes that help boost the responsiveness of your BBB under certain conditions. To perform this, we will explore the following topics:

• Kernel modifications for the purpose of creating real-time environments using:

  • RT_PREEMPT

  • Xenomai

• Programmable real-time units

And now for something completely contradictory: Linux is not real time. It is fast and efficient, but it is not a real-time system.

Harummph! But isn't Linux supposed...