Embedded Controller (EC) - ISpillMyDrink/UEFI-Repair-Guide GitHub Wiki

Embedded Controller (EC) are low-power, single-chip microcontroller embedded into most mobile computer platforms. They manage key system functions and control a multitude of peripherals. Some of the ECs typical functionality includes:

• Power management including control over the power on process
• Thermal management and fan control
• Embedded keyboard controller and PS/2 controller
• SMBus controller and battery interface
• Charger identification (for instance through a One-Wire interface)

The EC runs its own firmware that is either stored in chip internal flash or is provided by external flash components therefore any given ECs functionality depends highly on its specific programming.

The EC is typically connected to the southbridge through the Low Pin Count (LPC) bus or the Enhanced Serial Peripheral Interface (eSPI) bus.

Typical manufacturers for ECs are ENE, ITE, Microchip, Nuvoton, SMC, and Renesas.

For typical problems that can arise due to bad EC firmware refer to 6. Embedded Controller Firmware.

The Power On Process

On a typical mobile computer platform the EC is powered the second either the primary battery or AC adapter power is present. Once the EC is powered up it will start to load its firmware either from internal or external flash. Once booted the EC listens to the power button signal and once detected begins the power on process by powering up the southbridge. The exact procedure may vary by implementation.

Super I/O (SIO)

TODO

Baseboard Management Controller (BMC)

TODO