NUC970 Technical Reference Manual
Publication Release Date: Dec. 15, 2015
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Revision V1.30
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General DMA Controller (GDMA)
5.9
5.9.1 Overview
The chip has a two-channel general DMA controller with or without descriptor fetch operation, called
the GDMA. The two-channel GDMA performs the memory-to-memory data transfers without the CPU
intervention:
The on-chip GDMA can be started by the software. Software can also be used to restart the GDMA
operation after it has been stopped. The CPU can recognize the completion of a GDMA operation by
software polling or when it receives an internal GDMA interrupt. The GDMA controller can increment
source or destination address, decrement them as well, and conduct 8-bit (byte), 16-bit (half-word), or
32-bit (word) data transfers.
5.9.2 Features
AMBA AHB compliant
Descriptor and Non-Descriptor based function
Supports 8-data burst mode to boost performance
Provides support for external GDMA device
Demand mode speeds up external GDMA operations
5.9.3 Block Diagram
AHB Bus
Master/Slave Wrapper
Control
Registers
Buffer 0
(8 X 32 bit)
DMA
Controller
Channel 0
DMA
Controller
Channel 1
Buffer 1
(8 X 32 bit)
Figure 5.9-1 GDMA Block Diagram