Microcontroller units (MCUs) have a computer processor unit (CPU) core, various types of memory, input/output (I/O) functions, and a range of integrated peripherals. Field programmable gate arrays (FPGAs) don’t have any of these features and consist of many configurable (or programmable) logic blocks, with a programmable interconnect overlay surrounded by numerous general purpose I/Os (GPIOs). […]
Factors to consider when selecting an MCU
Selecting the MCU is an important activity when starting a new project. Underspecify the MCU, and performance suffers; over-specify it, and the budget suffers. In either case, suffering is unwanted and unnecessary. It’s prevented by taking a thoughtful and thorough approach to MCU selection. This FAQ begins with a review of the baseline performance numbers […]
What is the controller area network (CAN) bus?
The controller area network (CAN) bus was developed to support the networking of large numbers of electronic control units (ECUs) in automobiles. CAN is implemented using unshielded twisted pair (UTP) cabling, designed for reliability in electromagnetically noisy environments. CAN has evolved significantly since it was first introduced in 1986, along with early ECUs. Today, there […]
What is the onboard diagnostics system, OBDII?
OBDII is the second-generation onboard diagnostic (OBD) interface. The first generation of OBD coincided with the advent of onboard computers in vehicles. Initial OBD systems were intended to provide technicians with information on the status of various vehicle systems, with an indicator light on the dash to alert drivers of a malfunction. OBDII includes more […]
How is the MOST bus optimized for the automotive industry?
The media-oriented systems transport (MOST) bus was initially intended for implementation on optical fiber to support high bit rates, but fiber and copper transport layers are currently defined. MOST provides a solution for automotive peripherals like radios, CD and DVD players, GPS navigation systems, and infotainment electronic control units (ECUs). This FAQ describes the MOST […]
What is the ideal Ethernet choice for automotive applications?
Ethernet is gaining popularity in several automotive applications. It can handle high data rates with lower latency and lesser weight than controller area network (CAN) and local interconnect network (LIN) buses. However, conventional Ethernet developed for information technology (IT) infrastructure applications is too sensitive to interference and too noisy for most automotive applications. This article […]
What is the FlexRay communications network?
FlexRay is an ISO-standardized, deterministic, fault-tolerant, high-speed communications bus with applications in steer-by-wire, drive-by-wire, brake-by-wire, adaptive cruise control, active suspension, and other safety and drivetrain control systems. This FAQ offers a top-level comparison of FlexRay with the controller area network (CAN) and local interconnect network (LIN) buses, details the FlexRay communications cycle, and reviews FlexRay […]
What is the local interconnect network (LIN) bus?
The local interconnect network (LIN) bus is a single-wire bus (using the chassis ground) that enables the inexpensive integration of sensors and actuators in automobile networks. It can be used to create small subnets and can communicate over a power distribution system with a DC-LIN transceiver. This FAQ reviews the basics of LIN networks, details […]
What are basic logic gates?
Logic gates are the building blocks of digital circuits. The basic logic gates include AND, OR, NOT, NAND, NOR, XOR, and XNOR. They can be implemented in digital hardware using transistors and/or diodes. In a few applications, they are implemented using electromechanical relays, fluidics, pneumatics, or optical elements. A series of logic gates can be […]
Security standards and MCUs
Security is an important concern for developers of all types of systems. This FAQ reviews several important security standards for IoT cyber security, security vulnerabilities in industrial automation and control systems, standards for analyzing and identifying secure coding errors in C applications, and concepts of application software security and levels of trust. The European Telecommunications […]
