LM3S3749 Datasheet, PDF (306/898 Pages) Texas Instruments – Stellaris® LM3S3749 Microcontroller

Micro Direct Memory Access (μDMA)
alternate control structures to switch back and forth between buffers as the data flows to or from
the peripheral.
Refer to Figure 8-2 on page 306 for an example showing operation in Ping-Pong mode.
Figure 8-2. Example of Ping-Pong DMA Transaction
μDMA Controller
SOURCE
Primary Structure DEST
transfers using BUFFER A
BUFFER A
Cortex-M3 Processor
Peripheral/uDMA _Interrupt
SOURCE
Alternate Structure DEST
transfers using BUFFER B
BUFFER B
Peripheral/uDMA _Interrupt
SOURCE
Primary Structure
DEST
transfers using BUFFER A
BUFFER A
Peripheral/uDMA _Interrupt
SOURCE
Alternate Structure DEST
transfers using BUFFER B
BUFFER B
· Process data in BUFFER A
· Reload primary structure
· Process data in BUFFER B
· Reload alternate structure
· Process data in BUFFER B
· Reload alternate structure
306
November 17, 2011
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