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An embedded controller (EC) is a microcontroller in computers that handles various system tasks that the operating system does not handle. == Tasks == A generic embedded controller often has the following tasks: *Receiving and processing signals from the keyboard〔http://www.computer-engineering.org/ps2keyboard/〕 and other buttons and switches (e.g., power button, laptop lid switch)〔http://www.ami.com/ami_downloads/Embedded_Controller_Data_Sheet.pdf〕 *Turning the computer on and off *Controlling access to the A20 line〔http://www.win.tue.nl/~aeb/linux/kbd/A20.html〕 *Thermal measurement and response including fan control, CPU throttling, and emergency shutdown in response to rising temperatures *Controlling indicator LEDs *Managing the battery charger and the battery〔 *Allowing remote diagnostics and remediation over the network *Performing software-requested CPU reset〔 *Controlling the watchdog timer〔 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 almost always 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. A Trusted Platform Module contains an embedded controller that performs cryptographic functions and nothing else. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Embedded controller」の詳細全文を読む スポンサード リンク
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