DMA_CfgDescrSGAlt_TypeDef Struct Reference

Configuration structure for alternate scatter-gather descriptor.

#include <em_dma.h>

Data Fields

void * src
Pointer to location to transfer data from.
void * dst
Pointer to location to transfer data to.
DMA_DataInc_TypeDef dstInc
Destination increment size for each DMA transfer.
DMA_DataInc_TypeDef srcInc
Source increment size for each DMA transfer.
DMA_DataSize_TypeDef size
DMA transfer unit size.
DMA_ArbiterConfig_TypeDef arbRate
Arbitration rate, i.e., number of DMA transfers done before re-arbitration takes place.
uint16_t nMinus1
Number of DMA transfers minus 1 to do.
uint8_t hprot
HPROT signal state, refer to reference manual, DMA chapter for further details.
bool peripheral
Specify if a memory or peripheral scatter-gather DMA cycle.

Configuration structure for alternate scatter-gather descriptor.

Field Documentation

src

void* DMA_CfgDescrSGAlt_TypeDef::src

Pointer to location to transfer data from.

dst

void* DMA_CfgDescrSGAlt_TypeDef::dst

Pointer to location to transfer data to.

dstInc

DMA_DataInc_TypeDef DMA_CfgDescrSGAlt_TypeDef::dstInc

Destination increment size for each DMA transfer.

srcInc

DMA_DataInc_TypeDef DMA_CfgDescrSGAlt_TypeDef::srcInc

Source increment size for each DMA transfer.

size

DMA_DataSize_TypeDef DMA_CfgDescrSGAlt_TypeDef::size

DMA transfer unit size.

arbRate

DMA_ArbiterConfig_TypeDef DMA_CfgDescrSGAlt_TypeDef::arbRate

Arbitration rate, i.e., number of DMA transfers done before re-arbitration takes place.

nMinus1

uint16_t DMA_CfgDescrSGAlt_TypeDef::nMinus1

Number of DMA transfers minus 1 to do.

Must be <= 1023.

hprot

uint8_t DMA_CfgDescrSGAlt_TypeDef::hprot

HPROT signal state, refer to reference manual, DMA chapter for further details.

Normally set to 0 if protection is not an issue. The following bits are available:

  • bit 0 - HPROT[1] control for source read accesses, privileged/non-privileged access.
  • bit 3 - HPROT[1] control for destination write accesses, privileged/non-privileged access.

peripheral

bool DMA_CfgDescrSGAlt_TypeDef::peripheral

Specify if a memory or peripheral scatter-gather DMA cycle.

Notice that this parameter should be the same for all alternate descriptors.

  • true - this is a peripheral scatter-gather cycle.
  • false - this is a memory scatter-gather cycle.