The Intel(R) Serial IO SPI Host Controller - 34AB is a device driver for the Serial IO (Input/Output) Controller that allows communication with the Serial Peripheral Interface (SPI) hardware on Intel-based systems. It is part of the Intel Serial I/O Technology used in modern Intel chipsets (often found in Intel Core processors and related platforms). The driver is necessary for systems that include hardware that communicates via SPI, such as sensors, peripheral devices, or embedded systems.