Datasheet

Chapter 12. DMA Controller Module 12-1
Chapter 12
DMA Controller Module
This chapter describes the MCF5407 DMA controller module. It provides an overview of
the module and describes in detail its signals and registers. The latter sections of this
chapter describe operations, features, and supported data transfer modes in detail.
12.1 Overview
The direct memory access (DMA) controller module provides an efficient way to move
blocks of data with minimal processor interaction. The DMA module, shown in
Figure 12-1, provides four channels that allow byte, word, or longword operand transfers.
Each channel has a dedicated set of registers that define the source and destination
addresses (SARn and DARn), byte count (BCRn), and control and status (DCRn and
DSRn). Transfers can be dual or single address to off-chip devices or dual address to
on-chip devices, such as UART, SDRAM controller, and parallel port.
Figure 12-1. DMA Signal Diagram
MUX
Arbitration/
Interface Bus
Data Path
Control
Internal
External
ChannelChannel
MUX
Registered
Data Path
SAR0
DAR0
BCR0
DCR0
DSR0
Channel 0
Interrupts
SAR1
DAR1
BCR1
DCR1
DSR1
Channel 1
SAR2
DAR2
BCR2
DCR2
DSR2
Channel 2
SAR3
DAR3
BCR3
DCR3
DSR3
Channel 3
Bus
Requests
Attributes
Current Master Attributes
Write Bus DataRead Bus Data
External Bus Address
External Bus Size
Channel
Enables
Requests
Bus Signals
Control
Control