The NuttX Engineer

An Introduction to Apache Nuttx Apache NuttX is a real-time operating system (RTOS) for microcontrollers (MCUs). In this article, I discuss what the system consists of, its major features, and when it should be considered for embedded system software development. I also discuss an example in which I use NuttX RTOS and an ESP32 to read a BMP180 barometric pressure sensor. Topics Discussed What are the features of Apache NuttX RTOS? When should I use Apache NuttX RTOS for embedded software development? How do I deploy Apache NuttX on an ESP32? Tech Used Apache NuttX RTOS ESP32 microcontroller BMP180 barometric pressure sensor Embedded systems and software needs to be reliable. This means embedded software should be designed to work under highly variable conditions; it must be well-developed, well-tested and extensively validated. One way to ensure good embedded software design and performance is by using a reliable operating system. The major advantage of using an operating system in embedded system software is to delegate critical features—such as memory management, CPU usage, network management, and I/O management—to the operating system itself, so developers can focus their efforts on developing applications for the embedded system software. In embedded systems, it’s common to use a real-time operating system (RTOS), due to its small footprint (compared to a general purpose operating system) and real-time features—a requirement for some embedded software. In this article, you’ll be introduced to the Apache NuttX RTOS, and you’ll learn how to make embedded software to read a Bosch BMP180 barometric pressure sensor, using an Espressif ESP32 microcontroller/System-on-Chip (MCU/SoC) with NuttX. Figure 1 Espressif ESP32-DevKitC HARDWARE REQUIREMENTS To reproduce the project described here, you’ll need the following electronic components: ESP32-DevKitC board (Espressif) (Figure 1) Micro-US