![ARTERY AT32F435 Series Скачать руководство пользователя страница 151](http://html1.mh-extra.com/html/artery/at32f435-series/at32f435-series_reference-manual_2977592151.webp)
AT32F435/437
Series Reference Manual
2022.11.11
Page 151
Rev 2.03
9.3.3
Arbiter
When several channels are enabled simultaneously, the arbiter will restart arbitration after full data
transfer by the master controller. The channel with very high priority waits until the channel of the master
controller has completed data transfers before taking control of it. The master controller will re-arbitrate
to serve other channels as long as the channel completes a single transfer based on the master
controller priority.
Figure 9-2 Re-arbitrate after request/acknowledge
dma_req
dma_ack
One single transfer
Antother single transfer
Re-arbitrate
Re-arbitrate
9.3.4
Programmable data transfer width
Transfer width of the source data and destination data is programmable through the PWIDTH and
MWIDTH bits in the DMA_CxCTRL register. When PWIDTH is not equal to MWIDTH, it can be aligned
according to the settings of PWIDTH/ MWIDTH.
Figure 9-3 PW IDTH: byte, MW IDTH: half-word
B3
B2
B1
B0
Half-word3
Half-word2
Half-word1
Half-word0
4
th
3
rd
2
nd
1
st
B3 B2 B1 B0
4
th
3
rd
2
nd
1
st
HW3 HW2 HW1 HW0
AHB Read Sequence
AHB Write Sequence