Intel® 700 Series Chipset Family On-Package Platform Controller Hub (PCH)

Datasheet, Volume 1 of 2
Supporting Raptor Lake - PX Platforms

ID 765585
Date 01/30/2023
Version 001
Document Table of Contents

16550 8-bit Addressing - Debug Driver Compatibility

Note:The PCH UART host controller is not compatible with legacy UART 16550 debug-port drivers. The UART host controller operates in 32-bit addressing mode only. UART 16550 legacy drivers only operate with 8-bit addressing. In order to provide compatibility with standard in-box legacy UART drivers a 16550 Legacy Driver mode has been implemented in the UART controller that will convert 8-bit addressed accesses from the 16550 legacy driver to the 32-bit addressing that the UART host controller supports.The UART 16550 8-bit Legacy mode only operates with PIO transactions. DMA transactions are not supported in this mode.