ST STM32F410 User Manual

RM0401 Rev 3 167/771
RM0401 Direct memory access controller (DMA)
197
8.3.5 Arbiter
An arbiter manages the 8 DMA stream requests based on their priority for each of the two
AHB master ports (memory and peripheral ports) and launches the peripheral/memory
access sequences.
Priorities are managed in two stages:
• Software: each stream priority can be configured in the DMA_SxCR register. There are
four levels:
– Very high priority
– High priority
– Medium priority
– Low priority
• Hardware: If two requests have the same software priority level, the stream with the
lower number takes priority over the stream with the higher number. For example,
stream 2 takes priority over stream 4.
8.3.6 DMA streams
Each of the 8 DMA controller streams provides a unidirectional transfer link between a
source and a destination.
Each stream can be configured to perform:
• Regular type transactions: memory-to-peripherals, peripherals-to-memory or memory-
to-memory transfers
• Double-buffer type transactions: double buffer transfers using two memory pointers for
the memory (while the DMA is reading/writing from/to a buffer, the application can
write/read to/from the other buffer).
The amount of data to be transferred (up to 65535) is programmable and related to the
source width of the peripheral that requests the DMA transfer connected to the peripheral
AHB port. The register that contains the amount of data items to be transferred is
decremented after each transaction.
Table 30. DMA2 request mapping
Peripheral
requests
Stream 0 Stream 1 Stream 2 Stream 3 Stream 4 Stream 5 Stream 6 Stream 7
Channel 0 ADC1 - - - ADC1 -
TIM1_CH1
TIM1_CH2
TIM1_CH3
-
Channel 1 - - - - - - - -
Channel 2 - - SPI1_TX SPI5_RX SPI5_TX - - -
Channel 3 SPI1_RX - SPI1_RX SPI1_TX - SPI1_TX - -
Channel 4 - - USART1_RX - - USART1_RX - USART1_TX
Channel 5 - USART6_RX USART6_RX - - SPI5_TX USART6_TX USART6_TX
Channel 6 TIM1_TRIG TIM1_CH1 TIM1_CH2 TIM1_CH1
TIM1_CH4
TIM1_TRIG
TIM1_COM
TIM1_UP TIM1_CH3 -
Channel 7 - - - - - SPI5_RX SPI5_TX -

ST STM32F410 Specifications

General

Brand	ST
Model	STM32F410
Category	Microcontrollers
Language	English