lpc2377 NXP Semiconductors, lpc2377 Datasheet - Page 19

• Manufacturer Part Number: lpc2377
• Description: Single-chip 16-bit/32-bit Microcontroller; 512 Kb ?ash With Isp/iap, Ethernet, Usb 2.0, Can, And 10-bit Adc/dac
• Manufacturer: NXP Semiconductors

NXP Semiconductors
LPC2377_78_4
Product data sheet
7.8.1 Features
7.8 General purpose DMA controller
The GPDMA is an AMBA AHB compliant peripheral allowing selected LPC2377/78
peripherals to have DMA support.
The GPDMA enables peripheral-to-memory, memory-to-peripheral,
peripheral-to-peripheral, and memory-to-memory transactions. Each DMA stream
provides unidirectional serial DMA transfers for a single source and destination. For
example, a bidirectional port requires one stream for transmit and one for receive. The
source and destination areas can each be either a memory region or a peripheral, and
can be accessed through the AHB master.
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Static memory features include:
– Asynchronous page mode read
– Programmable Wait States (WST)
– Bus turnaround delay
– Output enable and write enable delays
– Extended wait
Two DMA channels. Each channel can support a unidirectional transfer.
The GPDMA can transfer data between the 8 kB SRAM and peripherals such as the
SD/MMC, two SSP, and I
Single DMA and burst DMA request signals. Each peripheral connected to the
GPDMA can assert either a burst DMA request or a single DMA request. The DMA
burst size is set by programming the GPDMA.
Memory-to-memory, memory-to-peripheral, peripheral-to-memory, and
peripheral-to-peripheral transfers.
Scatter or gather DMA is supported through the use of linked lists. This means that
the source and destination areas do not have to occupy contiguous areas of memory.
Hardware DMA channel priority. Each DMA channel has a specific hardware priority.
DMA channel 0 has the highest priority and channel 1 has the lowest priority. If
requests from two channels become active at the same time, the channel with the
highest priority is serviced first.
AHB slave DMA programming interface. The GPDMA is programmed by writing to the
DMA control registers over the AHB slave interface.
One AHB master for transferring data. This interface transfers data when a DMA
request goes active.
32-bit AHB master bus width.
Incrementing or non-incrementing addressing for source and destination.
Programmable DMA burst size. The DMA burst size can be programmed to more
efficiently transfer data. Usually the burst size is set to half the size of the FIFO in the
peripheral.
Internal four-word FIFO per channel.
Supports 8-bit, 16-bit, and 32-bit wide transactions.
Rev. 04 — 19 November 2008
2
S-bus interfaces.
Single-chip 16-bit/32-bit microcontroller
LPC2377/78
© NXP B.V. 2008. All rights reserved.
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