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UM10503
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User manual
Rev. 2.1 — 10 December 2015
524 of 1441
NXP Semiconductors
UM10503
Chapter 21: LPC43xx/LPC43Sxx General Purpose DMA (GPDMA)
Table 350. DMA Channel Control registers (CONTROL[0:7], 0x4000 210C (CONTROL0) to 0x4000 21EC (CONTROL7))
bit description
Bit
Symbol
Value Description
Reset
value
Access
11:0
TRANSFERSIZE
Transfer size in number of transfers. A write to this field sets the
size of the transfer when the DMA Controller is the flow
controller. The transfer size value must be set before the
channel is enabled. Transfer size is updated as data transfers
are completed.
A read from this field indicates the number of transfers
completed on the destination bus. Reading the register when
the channel is active does not give useful information because
by the time that the software has processed the value read, the
channel might have progressed. It is intended to be used only
when a channel is enabled and then disabled.
The transfer size value is not used if the DMA Controller is not
the flow controller.
0x0
R/W
14:12
SBSIZE
Source burst size. Indicates the number of transfers that make
up a source burst. This value must be set to the burst size of the
source peripheral, or if the source is memory, to the memory
boundary size (see
). The burst size is the amount of
data that is transferred when the BREQ signal goes active in the
source peripheral.
0x0
R/W
0x0
Source burst size = 1
0x1
Source burst size = 4
0x2
Source burst size = 8
0x3
Source burst size = 16
0x4
Source burst size = 32
0x5
Source burst size = 64
0x6
Source burst size = 128
0x7
Source burst size = 256
17:15
DBSIZE
Destination burst size. Indicates the number of transfers that
make up a destination burst transfer request. This value must
be set to the burst size of the destination peripheral or, if the
destination is memory, to the memory boundary size. The burst
size is the amount of data that is transferred when the BREQ
signal goes active in the destination peripheral.
0x0
R/W
0x0
Destination burst size = 1
0x1
Destination burst size = 4
0x2
Destination burst size = 8
0x3
Destination burst size = 16
0x4
Destination burst size = 32
0x5
Destination burst size = 64
0x6
Destination burst size = 128
0x7
Destination burst size = 256