SPRUI30H November 2015 – May 2024 DRA745 , DRA746 , DRA750 , DRA756
The eMMC/SD/SDIO host controller provides an interface between a local host (LH) such as a microprocessor unit (MPU) or digital signal processor (DSP) and either eMMC, SD® memory cards, or SDIO cards and handles eMMC/SD/SDIO transactions with minimal LH intervention.
Optionally, the controller is connected to the L3_MAIN interconnect to have a direct access to system memory. It also supports two direct memory access (DMA) slave channels or a DMA master access (in this case, slave DMA channels are deactivated) depending on its integration.
The eMMC/SD/SDIO host controller deals with eMMC/SD/SDIO protocol at transmission level, data packing, adding cyclic redundancy checks (CRCs), start/end bit, and checking for syntactical correctness.
The application interface can send every eMMC/SD/SDIO command and poll for the status of the adapter or wait for an interrupt request, which is sent back in case of exceptions or to warn of end of operation.
The application interface can read card responses or flag registers. It can also mask individual interrupt sources. All these operations can be performed by reading and writing control registers. The eMMC/SD/SDIO host controller also supports two DMA channels.
There are four eMMC/SD/SDIO host controllers inside the device. Figure 25-1 gives an overview of the eMMC/SD/SDIOi (i = 1 to 4) controllers.
Each controller has the following data width:
The eMMC/SD/SDIOi controller is also referred to as MMCi.