Introduction
5-5
System DMA Controller
The system DMA controller is controlled by the MPU (via the TIPB). The DMA
controller meets the high-rate-flow requirements of the multichannel applica-
tions used by wireless base stations.
The system DMA controller is designed for low-power operation. Its clock can
be automatically disabled as required. This function is synchronous to the
MPU TIPB and is entirely under hardware control. No specific programming
is required.
The functional features of the system DMA controller for general-purpose
transfers are:
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Nine general-purpose and one dedicated (LCD) DMA channels
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Software programmable DMA access priority-based on resource alloca-
tion versus processor (MPU or DSP) access. Through the assignment of
priority levels for each channel, the user can determine how the ports are
shared between channels.
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Concurrent DMA transfers capability
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Start of transfer on peripheral request or host request
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Byte alignment capability
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Byte packing/unpacking
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Byte transfer count
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Configurable indexes through memory for each channel source and
destination address register. The address may remain constant or post-
increment.
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Access available to all of the memory range (physical memory mapping
and I/O space)
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Seven ports available for different kinds of hardware resources. All data
exchanges are done with a simple handshake mechanism with request,
ready, and abort signals. All of the ports except the TIPB have burst access
capability.
J
EMIFS port
J
EMIFF port
J
IMIF port
J
MPUI port
J
TIPB
port
J
Local port
J
LCD port