mcf5407 Freescale Semiconductor, Inc, mcf5407 Datasheet - Page 317

• Manufacturer Part Number: mcf5407
• Description: Mcf5407 Coldfire Integrated Microprocessor User
• Manufacturer: Freescale Semiconductor, Inc

Any operation involving the DMA module follows the same three steps:
12.4 DMA Controller Module Programming Model
This section describes each internal register and its bit assignment. Note that there is no way
to prevent a write to a control register during a DMA transfer. Table 12-3 shows the
mapping of DMA controller registers.
• Single-address transfers—An external device can initiate a single-address transfer
1. Channel initialization—Channel registers are loaded with control information,
2. Data transfer—The DMA accepts requests for operand transfers and provides
3. Channel termination—Occurs after the operation is finished, either successfully or
by asserting DREQ. The MCF5407 provides address and control signals for
single-address transfers. The external device reads to or writes from the specified
address, as Figure 12-4 shows. External logic is required.
address pointers, and a byte-transfer count.
addressing and bus control for the transfers.
due to an error. The channel indicates the operation status in the channel’s DSR,
described in Section 12.4.5, “DMA Status Registers (DSR0–DSR3).”
Write:
Read:
Control Signals
Control Signals
Figure 12-4. Single-Address Transfers
Memory
Memory
Chapter 12. DMA Controller Module
Data
Data
DMA
DMA
DMA Controller Module Programming Model
Control Signals
Control Signals
Peripheral
Peripheral
12-5