LM3S5791_16 Datasheet, PDF (345/1336 Pages) Texas Instruments – Stellaris LM3S5791 Microcontroller

Stellaris^® LM3S5791 Microcontroller
7.2.6.4
Ping-Pong
Ping-Pong mode is used to support a continuous data flow to or from a peripheral. To use Ping-Pong
mode, both the primary and alternate data structures must be implemented. Both structures are set
up by the processor for data transfer between memory and a peripheral. The transfer is started
using the primary control structure. When the transfer using the primary control structure is complete,
the μDMA controller reads the alternate control structure for that channel to continue the transfer.
Each time this happens, an interrupt is generated, and the processor can reload the control structure
for the just-completed transfer. Data flow can continue indefinitely this way, using the primary and
alternate control structures to switch back and forth between buffers as the data flows to or from
the peripheral.
Refer to Figure 7-2 on page 346 for an example showing operation in Ping-Pong mode.
July 03, 2014
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