Chapter 16 Enhanced Direct Memory Access (eDMA)
MPC5606BK Microcontroller Reference Manual, Rev. 2
278
Freescale Semiconductor
16.4
Functional description
This section provides an overview of the microarchitecture and functional operation of the eDMA block.
251 /
0x1C [27]
E_SG
Enable scatter-gather processing. As the channel completes the outer
major loop, this flag enables scatter-gather processing in the current
channel. If enabled, the DMA engine uses DLAST_SGA as a memory
pointer to a 0-modulo-32 address containing a 32-byte data structure that
is loaded as the transfer control descriptor into the local memory.
NOTE: To support the dynamic scatter-gather coherency model, this field
is forced to zero when written to while the TCD.DONE bit is set.
0 The current channel’s TCD is normal format.
1 The current channel’s TCD specifies a scatter gather format. The
DLAST_SGA field provides a memory pointer to the next TCD to be
loaded into this channel after the outer major loop completes its
execution.
252 /
0x1C [28]
D_REQ
Disable hardware request. If this flag is set, the eDMA hardware
automatically clears the corresponding EDMA_ERQRL bit when the
current major iteration count reaches zero.
0 The channel’s EDMA_ERQRL bit is not affected.
1 The channel’s EDMA_ERQRL bit is cleared when the outer major loop
is complete.
253 /
0x1C [29]
INT_HALF
Enable an interrupt when major counter is half complete. If this flag is set,
the channel generates an interrupt request by setting the appropriate bit in
the EDMA_ERQRL when the current major iteration count reaches the
halfway point. Specifically, the comparison performed by the eDMA engine
is (CITER == (BITER >> 1)). This halfway point interrupt request is provided
to support double-buffered (also known as ping-pong) schemes, or other
types of data movement where the processor needs an early indication of
the transfer’s progress. CITER = BITER = 1 with INT_HALF enabled will
generate an interrupt as it satisfies the equation (CITER == (BITER >> 1))
after a single activation.
0 The half-point interrupt is disabled.
1 The half-point interrupt is enabled.
254 /
0x1C [30]
INT_MAJ
Enable an interrupt when major iteration count completes. If this flag is set,
the channel generates an interrupt request by setting the appropriate bit in
the EDMA_ERQRL when the current major iteration count reaches zero.
0 The end-of-major loop interrupt is disabled.
1 The end-of-major loop interrupt is enabled.
255 /
0x1C [31]
START
Channel start. If this flag is set the channel is requesting service. The
eDMA hardware automatically clears this flag after the channel begins
execution.
0 The channel is not explicitly started.
1 The channel is explicitly started via a software initiated service request.
1
The fields implemented at 0x8 depend on whether EDMA_CR(EMLM) is set to 0 or 1. Refer to
.
Table 16-19. TCD
n
field descriptions (continued)
Bits /
Word Offset
[n:n]
Name
Description
Содержание MPC5605BK
Страница 2: ...This page is intentionally left blank...
Страница 20: ...MPC5606BK Microcontroller Reference Manual Rev 2 20 Freescale Semiconductor...
Страница 103: ...MPC5606BK Microcontroller Reference Manual Rev 2 Freescale Semiconductor 103 Clocks and power...
Страница 104: ...MPC5606BK Microcontroller Reference Manual Rev 2 104 Freescale Semiconductor This page is intentionally left blank...
Страница 243: ...MPC5606BK Microcontroller Reference Manual Rev 2 Freescale Semiconductor 243 Core platform modules...
Страница 244: ...MPC5606BK Microcontroller Reference Manual Rev 2 244 Freescale Semiconductor This page is intentionally left blank...
Страница 395: ...MPC5606BK Microcontroller Reference Manual Rev 2 Freescale Semiconductor 395 Communication modules...
Страница 396: ...MPC5606BK Microcontroller Reference Manual Rev 2 396 Freescale Semiconductor This page is intentionally left blank...
Страница 548: ...Chapter 24 LIN Controller LINFlexD MPC5606BK Microcontroller Reference Manual Rev 2 548 Freescale Semiconductor...
Страница 645: ...MPC5606BK Microcontroller Reference Manual Rev 2 Freescale Semiconductor 643 Timers...
Страница 646: ...MPC5606BK Microcontroller Reference Manual Rev 2 644 Freescale Semiconductor This page is intentionally left blank...
Страница 715: ...MPC5606BK Microcontroller Reference Manual Rev 2 Freescale Semiconductor 713 ADC system...
Страница 716: ...MPC5606BK Microcontroller Reference Manual Rev 2 714 Freescale Semiconductor This page is intentionally left blank...
Страница 787: ...MPC5606BK Microcontroller Reference Manual Rev 2 Freescale Semiconductor 787 Memory...
Страница 788: ...MPC5606BK Microcontroller Reference Manual Rev 2 788 Freescale Semiconductor This page is intentionally left blank...
Страница 893: ...MPC5606BK Microcontroller Reference Manual Rev 2 Freescale Semiconductor 893 Integrity...
Страница 894: ...MPC5606BK Microcontroller Reference Manual Rev 2 894 Freescale Semiconductor This page is intentionally left blank...
Страница 943: ...MPC5606BK Microcontroller Reference Manual Rev 2 Freescale Semiconductor 943 Debug...
Страница 944: ...MPC5606BK Microcontroller Reference Manual Rev 2 944 Freescale Semiconductor This page is intentionally left blank...