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PXN20RM Datasheet, PDF (505/1376 Pages) Freescale Semiconductor, Inc – PXN20 Microcontroller
Chapter 23
DMA Channel Multiplexer (DMA_MUX)
23.1 Introduction
The DMA channel multiplexer (DMA_MUX) module allows for software selection of 32 out of 59
possible DMA sources. As many as 55 of these DMA sources are requests from peripherals, but four of
the peripheral sources are reserved and behave as always disabled sources. Four sources are always
enabled and generate a DMA request as soon as that source is selected. One source (the default for all
channels) is always disabled.
23.1.1 Block Diagram
A simplified block diagram of the DMA_MUX is shown in Figure 23-1.
Peripheral Source #1
Peripheral Source #2
Peripheral Source #3
DMA Channel #0
DMA Channel #1
DMA Channel #2
DMA Channel #3
DMA Channel #4
DMA Channel #5
DMA Channel #6
DMA Channel #7
DMA Channel #8
DMA Channel #9
DMA Channel #10
DMA Channel #11
Peripheral Source #55
DMA Channel #30
DMA Channel #31
Figure 23-1. DMA_MUX Block Diagram
Freescale Semiconductor
PXN20 Microcontroller Reference Manual, Rev. 1
23-1