Intel® Core™ Ultra 200H and 200U Series Processors

Datasheet, Volume 1 of 2

ID Date Version Classification
842704 05/27/2025 Public
Document Table of Contents

GPIO Blink (BK) and Serial Blink (SBK)

Certain GPIOs are capable of supporting blink (BK, or also referred to as PWM), and serial blink (SBK, or also referred to as Serial POST Codes). The BK and SBK are implemented as native functions muxed on selected GPIOs. To enable BK or SBK on a GPIO having the capability, BIOS needs to select the BK or SBK native function on the GPIO.

BK provides a programmable PWM wave. The Blink/PWM frequency and duty cycle is programmable through the PWM Control register.

SBK allows system software to serialize POST or other messages on GPIO to a serial monitor. The Serial Blink messages is programmed through the Serial Blink Command/Status and Serial Blink Data registers.