Embedded controller

Last updated

An Embedded Controller (EC) is a microcontroller in computers that handles various system tasks. Now it is usually merged with Super I/O, especially on mobile platforms (such as laptop).

Contents

Tasks

An embedded controller can have the following tasks:

As a core system component, the embedded controller is always on when power is supplied to the mainboard. To communicate with the main computer system, several forms of communication can be used, including ACPI, SMBus, or shared memory.

The embedded controller has its own RAM, independent of that used by the main computer system, and often its own flash ROM on which the controller's software is stored. Many BIOS updates also include upgrades for the embedded controller firmware.

An embedded controller is sometimes known as a "Keyboard Controller BIOS", which comes from the fact that the embedded controller evolved from the keyboard controller and often still is used as a keyboard controller. Even today, an ACPI embedded controller communicates with the CPU by using the same I/O ports that keyboard controllers used in the past.

Ergonomics

Although the embedded controller is very "deep" in the system, it is important to the user because it performs functions such as fan control and thermal management. Computer systems such as laptops often produce large amounts of heat which must be dissipated. This is typically done by activating a fan to blow air over the components that are producing heat; the fan is not simply turned on or off, but is driven at high speed by the embedded controller for a short time and then left running at low speed until the temperature has decreased sufficiently. Such a control scheme can be uncomfortable from an ergonomic point of view, as the change in fan speed is noticeable to the user, especially if this occurs regularly and if the fan is clearly audible.

To prevent this, some embedded controllers are designed to run the fans at a constant speed over a larger range of temperatures and will only increase fan speed when the system is close to overheating. In this case, the ergonomics of the system are improved because the fan is quieter, as it is controlled to rotate at a lower speed and does not change speed as often. However, when the temperature does cross the controller's threshold, it will take much longer to reduce the temperature to safe levels.

To change the fan control policy, updates to the embedded controller's firmware are usually necessary.

Common Brands

See also

Related Research Articles

<span class="mw-page-title-main">BIOS</span> Firmware for hardware initialization and OS runtime services

In computing, BIOS is firmware used to provide runtime services for operating systems and programs and to perform hardware initialization during the booting process. The BIOS firmware comes pre-installed on an IBM PC or IBM PC compatible's system board and exists in some UEFI-based systems to maintain compatibility with operating systems that do not support UEFI native operation. The name originates from the Basic Input/Output System used in the CP/M operating system in 1975. The BIOS originally proprietary to the IBM PC has been reverse engineered by some companies looking to create compatible systems. The interface of that original system serves as a de facto standard.

<span class="mw-page-title-main">Motherboard</span> Main printed circuit board (PCB) for a computing device

A motherboard is the main printed circuit board (PCB) in general-purpose computers and other expandable systems. It holds and allows communication between many of the crucial electronic components of a system, such as the central processing unit (CPU) and memory, and provides connectors for other peripherals. Unlike a backplane, a motherboard usually contains significant sub-systems, such as the central processor, the chipset's input/output and memory controllers, interface connectors, and other components integrated for general use.

<span class="mw-page-title-main">Firmware</span> Low-level computer software

In computing, firmware is a specific class of computer software that provides the low-level control for a device's specific hardware. Firmware, such as the BIOS of a personal computer, may contain basic functions of a device, and may provide hardware abstraction services to higher-level software such as operating systems. For less complex devices, firmware may act as the device's complete operating system, performing all control, monitoring and data manipulation functions. Typical examples of devices containing firmware are embedded systems, home and personal-use appliances, computers, and computer peripherals.

<span class="mw-page-title-main">Laptop</span> Personal computer for mobile use

A laptop computer or notebook computer, also known as a laptop or notebook, is a small, portable personal computer (PC). Laptops typically have a clamshell form factor with a flat panel screen on the inside of the upper lid and an alphanumeric keyboard and pointing device on the inside of the lower lid, although 2-in-1 PCs with a detachable keyboard are often marketed as laptops or as having a "laptop mode". Most of the computer's internal hardware is fitted inside the lower lid enclosure under the keyboard, although many laptops have a built-in webcam at the top of the screen and some modern ones even feature a touch-screen display. In most cases, unlike tablet computers which run on mobile operating systems, laptops tend to run on desktop operating systems, which were originally developed for desktop computers.

Underclocking, also known as downclocking, is modifying a computer or electronic circuit's timing settings to run at a lower clock rate than is specified. Underclocking is used to reduce a computer's power consumption, increase battery life, reduce heat emission, and it may also increase the system's stability, lifespan/reliability and compatibility. Underclocking may be implemented by the factory, but many computers and components may be underclocked by the end user.

<span class="mw-page-title-main">Southbridge (computing)</span> One of the two chips in the core logic chipset architecture on a PC motherboard

The southbridge is one of the two chips in the core logic chipset on older personal computer (PC) motherboards, the other being the northbridge. As of 2023, most personal computer devices no longer use a set of two chips, and instead have a single chip acting as the 'chipset', for example Intel's Z790 chipset.

<span class="mw-page-title-main">Geode (processor)</span> Series of x86-compatible processor

Geode was a series of x86-compatible system-on-a-chip (SoC) microprocessors and I/O companions produced by AMD, targeted at the embedded computing market.

The Intelligent Platform Management Interface (IPMI) is a set of computer interface specifications for an autonomous computer subsystem that provides management and monitoring capabilities independently of the host system's CPU, firmware and operating system. IPMI defines a set of interfaces used by system administrators for out-of-band management of computer systems and monitoring of their operation. For example, IPMI provides a way to manage a computer that may be powered off or otherwise unresponsive by using a network connection to the hardware rather than to an operating system or login shell. Another use case may be installing a custom operating system remotely. Without IPMI, installing a custom operating system may require an administrator to be physically present near the computer, insert a DVD or a USB flash drive containing the OS installer and complete the installation process using a monitor and a keyboard. Using IPMI, an administrator can mount an ISO image, simulate an installer DVD, and perform the installation remotely.

<span class="mw-page-title-main">Toughbook</span> Line of rugged laptop computers made by the Panasonic Corporation

The Panasonic Toughbook is a line of rugged computers produced and marketed by the Panasonic Corporation. It was introduced in 1996 with the CF-25. The Toughbook laptops are used in a wide variety of industries, including construction, defense, emergency services, government, healthcare, law enforcement, manufacturing, oil, gas, telecom, and utilities. The Toughbook brand mainly competes with other lines of rugged computers, such as Dell's Rugged Extreme.

<span class="mw-page-title-main">In-system programming</span> Embedded system programming technique

In-system programming (ISP), or also called in-circuit serial programming (ICSP), is the ability of some programmable logic devices, microcontrollers, chipsets and other embedded devices to be programmed while installed in a complete system, rather than requiring the chip to be programmed prior to installing it into the system. It also allows firmware updates to be delivered to the on-chip memory of microcontrollers and related processors without requiring specialist programming circuitry on the circuit board, and simplifies design work.

<span class="mw-page-title-main">Super I/O</span> Class of I/O controller integrated circuits

Super I/O is a class of I/O controller integrated circuits that began to be used on personal computer motherboards in the late 1980s, originally as add-in cards, later embedded on the motherboards. A super I/O chip combines interfaces for a variety of low-bandwidth devices. Now it is mostly merged with EC.

System Management Mode is an operating mode of x86 central processor units (CPUs) in which all normal execution, including the operating system, is suspended. An alternate software system which usually resides in the computer's firmware, or a hardware-assisted debugger, is then executed with high privileges.

<span class="mw-page-title-main">Apple–Intel architecture</span> Unofficial name used for Macintosh models that use Intel x86 processors

The Apple–Intel architecture, or Mactel, is an unofficial name used for Macintosh personal computers developed and manufactured by Apple Inc. that use Intel x86 processors, rather than the PowerPC and Motorola 68000 ("68k") series processors used in their predecessors or the ARM-based Apple silicon SoCs used in their successors. As Apple changed the architecture of its products, they changed the firmware from the Open Firmware used on PowerPC-based Macs to the Intel-designed Extensible Firmware Interface (EFI). With the change in processor architecture to x86, Macs gained the ability to boot into x86-native operating systems, while Intel VT-x brought near-native virtualization with macOS as the host OS.

The Power Management Unit (PMU) is a microcontroller that governs power functions of digital platforms. This microchip has many similar components to the average computer, including firmware and software, memory, a CPU, input/output functions, timers to measure intervals of time, and analog to digital converters to measure the voltages of the main battery or power source of the computer. The PMU is one of the few items to remain active even when the computer is completely shut down, powered by the backup battery.

Dynamic frequency scaling is a power management technique in computer architecture whereby the frequency of a microprocessor can be automatically adjusted "on the fly" depending on the actual needs, to conserve power and reduce the amount of heat generated by the chip. Dynamic frequency scaling helps preserve battery on mobile devices and decrease cooling cost and noise on quiet computing settings, or can be useful as a security measure for overheated systems.

<span class="mw-page-title-main">Computer hardware</span> Physical components of a computer

Computer hardware includes the physical parts of a computer, such as the central processing unit (CPU), random access memory (RAM), motherboard, computer data storage, graphics card, sound card, and computer case. It includes external devices such as a monitor, mouse, keyboard, and speakers.

<span class="mw-page-title-main">Keyboard controller (computing)</span>

In computing, a keyboard controller is a device that interfaces a keyboard to a computer. Its main function is to inform the computer when a key is pressed or released. When data from the keyboard arrives, the controller raises an interrupt to allow the CPU to handle the input.

<span class="mw-page-title-main">Intel Management Engine</span> Autonomous computer subsystem

The Intel Management Engine (ME), also known as the Intel Manageability Engine, is an autonomous subsystem that has been incorporated in virtually all of Intel's processor chipsets since 2008. It is located in the Platform Controller Hub of modern Intel motherboards.

<span class="mw-page-title-main">Surface Book 2</span> 2-in-1 PC by Microsoft

The Surface Book 2 is the second generation of the Surface Book, part of the Microsoft Surface line of personal computers. It is a 2-in-1 PC which can be used like a conventional laptop, or the screen can be detached and used separately as a tablet, with touch and stylus input. In addition to the 13.5-inch screen available in the original Surface Book introduced two years before, it is also available in a 15-inch screen model. It was released in November 2017, and replaced in Microsoft's product line by the Surface Book 3 in May 2020.

<span class="mw-page-title-main">Framework Computer</span> American computer company

Framework Computer, Inc. is an American laptop computer manufacturer. The company positions itself as a proponent of the electronics right to repair movement, and their laptops are designed to be easy to disassemble, with replaceable parts.

References

  1. 1 2 "The PS/2 Keyboard Interface". Archived from the original on 2016-03-04.
  2. 1 2 3 "AMI Embedded Controller (EC) Firmware Solution" (PDF). Archived from the original (PDF) on 2016-03-04. Retrieved 2014-12-28.
  3. "A20 - a pain from the past".
  4. "EC (Embedded Controller)". Nuvoton. Retrieved 19 October 2023.
  5. "Embedded Controllers and Keyboar Controllers". Microchip Technology. Retrieved 19 October 2023.