Embedded controller: Difference between revisions

Revision as of 21:11, 5 January 2017

Revision as of 23:31, 28 March 2017

Line 21:

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 [[Advanced Configuration and Power Interface|ACPI]], [[SMBus]], or [[Shared memory (interprocess communication)|shared memory]].

The embedded controller has its own [[Random-access memory|RAM]], independent of that used by the main computer system, and almost alwaysoften 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.