DMA/QDMA
channel
logic
PaRAM
Transfer
request
submission
Completion
and error
interrupt
logic
EDMA3CC_INT[7:0]
EDMA3CC_MPINT
Completion
detection
To/from
EDMA3
programmer
Channel controller
TC0
Transfer
controllers
Read/write
commands
and data
EDMA3TC0_
ERRINT0
MMR
TC3
commands
Read/write
and data
MMR
EDMA3TC3_
ERRINT
EDMA3CC_ERRINT
access
access
Event
queues
Introduction
11.1 Introduction
The enhanced direct memory access (EDMA3) controller’s primary purpose is to service user-
programmed data transfers between two memory-mapped slave endpoints on the device.
Typical usage includes, but is not limited to the following:
•
Servicing software-driven paging transfers (e.g., transfers from external memory, such as DDR2 to
internal device memory).
•
Servicing event-driven peripherals, such as a serial port.
•
Performing sorting or sub-frame extraction of various data structures.
•
Offloading data transfers from the main device CPU(s).
The EDMA3 controller consists of two principal blocks:
•
EDMA3 channel controller (EDMA3CC).
•
EDMA3 transfer controller(s) (EDMA3TC).
The EDMA3 channel controller serves as the user interface for the EDMA3 controller. The EDMA3CC
includes parameter RAM (PaRAM), channel control registers, and interrupt control registers. The
EDMA3CC serves to prioritize incoming software requests or events from peripherals and submits transfer
requests (TRs) to the transfer controller.
The EDMA3 transfer controllers are slaves to the EDMA3 channel controller that is responsible for data
movement. The transfer controller issues read/write commands to the source and destination addresses
that are programmed for a given transfer. The operation is transparent to user.
11.1.1 EDMA3 Controller Block Diagram
shows a block diagram for the EDMA3 controller.
Figure 11-1. EDMA3 Controller Block Diagram
11.1.2 Third-Party Channel Controller (TPCC) Overview
11.1.2.1 TPCC Features
The general features of the TPCC module are:
•
Up to 64 DMA Channels
–
Channels triggered by:
•
Event Synchronization
•
Manual Synchronization (CPU write to ‘Event Set Register’)
•
Chain Synchronization (completion of one transfer chains to the next)
–
Parameterizable support for programmable DMA Channel to PaRAM mapping
870
Enhanced Direct Memory Access (EDMA)
SPRUH73H – October 2011 – Revised April 2013
Copyright © 2011–2013, Texas Instruments Incorporated