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Figure 14 Transmission Width with Source of 32bits and Target of 16bits
0x0
0x1
Data0
Data1
0x2
0x3
Data2
Data3
0x4
0x5
Data4
Data5
0x6
0x7
Data6
Data7
0x8
0x9
Data8
Data9
0xA
0xB
DataA
DataB
0xC
0xD
DataC
DataD
0xE
0xF
DataE
DataF
Data0
Data1
Data4
Data5
Data8
Data9
DataC
DataD
0x0
0x1
0x2
0x3
0x4
0x5
0x6
0x7
Source
Target
9.3.2.3
Address setting
The transmission address supports two modes: fixed mode and pointer
increment mode.
Transmission address pointer increment mode
The automatic pointer increment of peripheral and memory is completed through
the PERIMODE bit and MIMODE bit of configuration register DMA_CHCFGx.
The next address to be transmitted is the one by adding the increment to the
previous address. The increment depends on the selected data width.
9.3.2.4
Transmission mode
There are two channel configuration modes: non-circular mode and circular
mode.
Non-circular mode
When the data transmission is finished, the DMA operation will not be performed
any more, and the new DMA transmission will be started. When the DMA
channel is not working, the register DMA_CHNDATAx will rewrite the
transmission value.
Circular mode
After data transmission, the content of the register DMA_CHNDATAx will be
automatically reloaded to the previously configured value, and the peripheral
address register DMA_CHPADDRx and the memory address register
DMA_CHMADDRx will also be reloaded as the initial base address.
The configuration method is as follows:
Set the CIRMODE bit of the configuration register DMA_CHCFGx to 1
to turn on the circular mode
This mode is used to process continuous peripheral requests. When
the number of data transmission becomes 0, it will automatically return