Freescale Semiconductor MCF52277 Reference Manual page 290

Enhanced Direct Memory Access (eDMA)
eDMA
eDMA Engine
Read Data
Write Data
Address
In the second part of the basic data flow
(address path, data path, and control) sequence through the required source reads and destination writes to
perform the actual data movement. The source reads are initiated and the fetched data is temporarily stored
in the data path block until it is gated onto the internal bus during the destination write. This source
read/destination write processing continues until the minor byte count has transferred.
17-26
Data Path
Figure 17-29. eDMA Operation, Part 1
(Figure
MCF52277 Reference Manual, Rev. 1
Transfer
Control
Descriptor (TCD)
64
Program Model/
Channel Arbitration
Address Path
Control
eDMA Peripheral
Request
17-30), the modules associated with the data transfer
Write Address
Write Data
0
1
2
n-1
Read Data
eDMA Done
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