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DMA Channel Multiplexer (DMA_MUX)
PXN20 Microcontroller Reference Manual, Rev. 1
Freescale Semiconductor
23-9
Figure 23-3. DMA_MUX Channel 0–7 Block Diagram
The DMA channel triggering capability allows the system to schedule regular DMA transfers, usually on
the transmit side of certain peripherals, without the intervention of the processor. This trigger works by
gating the request from the peripheral to the DMA until a trigger event has been seen. This is illustrated in
.
Figure 23-4. DMA_MUX Channel Triggering: Normal Operation
After the DMA request has been serviced, the peripheral negates its request, effectively resetting the gating
mechanism until the peripheral re-asserts its request AND
the next trigger event is seen. This means that
if a trigger is seen, but the peripheral is not requesting a transfer, that triggered is ignored. This situation
is illustrated in
Peripheral Source #1
Peripheral Source #2
Peripheral Source #3
Peripheral Source #55
DMA Channel #n
Always Disabled
Always Enabled
CHCONFIGn[SOURCE]
PIT Trigger #n+1
1
0
CHCONFIGn[TRIG]
Source #60
Always Enabled
Source #63
n = 0 to 7
Source #0
Peripheral Request
Trigger
DMA Request
Summary of Contents for PXN2020
Page 1: ...PXN20 Microcontroller Reference Manual Devices Supported PXN2020 PXN2120 PXN20RM Rev 1 06 2011...
Page 42: ...PXN20 Microcontroller Reference Manual Rev 1 lxiv Freescale Semiconductor...
Page 64: ...Introduction PXN20 Microcontroller Reference Manual Rev 1 1 22 Freescale Semiconductor...
Page 112: ...Signal Description PXN20 Microcontroller Reference Manual Rev 1 3 44 Freescale Semiconductor...
Page 118: ...Resets PXN20 Microcontroller Reference Manual Rev 1 4 6 Freescale Semiconductor...
Page 372: ...e200z6 Core Z6 PXN20 Microcontroller Reference Manual Rev 1 13 8 Freescale Semiconductor...
Page 412: ...e200z0 Core Z0 PXN20 Microcontroller Reference Manual Rev 1 14 14 Freescale Semiconductor...
Page 821: ...Media Local Bus MLB PXN20 Microcontroller Reference Manual Rev 1 Freescale Semiconductor 27 49...
Page 822: ...Media Local Bus MLB PXN20 Microcontroller Reference Manual Rev 1 27 50 Freescale Semiconductor...
Page 1376: ...Memory Map PXN20 Microcontroller Reference Manual Rev 1 A 118 Freescale Semiconductor...