dma.h File Reference

Function prototypes for the DMA driver. More...

#include <stdint.h>
#include "stm32f4xx.h"
#include "defines.h"

Go to the source code of this file.

Data Structures
struct	DMAStreamRegs
	Contains DMA stream registers. More...
struct	DMARegs
	Contains DMA registers. More...
struct	DMAStreamConfig
	Contains DMA stream options. More...
struct	DMAStreamISR
	Contains DMA stream interrupt configuration. More...

Macros
#define	DMA(x)

Typedefs
typedef enum dma_peripheral	dma_peripheral_t
	Available DMA peripherals.
typedef enum dma_dir	dma_dir_t
	Available DMA directions.
typedef enum dma_datasize	dma_datasize_t
	Available DMA data sizes.
typedef enum dma_priority	dma_priority_t
	Available DMA priorities.

Enumerations
enum	dma_peripheral { DMA_PERIPH_1 = 0x00 , DMA_PERIPH_2 = 0x01 }
	Available DMA peripherals.
enum	dma_dir { DMA_DIR_PER2MEM = 0x00 , DMA_DIR_MEM2PER = 0x01 , DMA_DIR_MEM2MEM = 0x02 }
	Available DMA directions.
enum	dma_datasize { DMA_DATASIZE_BYTE = 0x00 , DMA_DATASIZE_HWRD = 0x01 , DMA_DATASIZE_WORD = 0x02 }
	Available DMA data sizes.
enum	dma_priority { DMA_PRIORITY_LOW = 0x00 , DMA_PRIORITY_MED = 0x01 , DMA_PRIORITY_HIG = 0x02 , DMA_PRIORITY_VHI = 0x03 }
	Available DMA priorities.

Functions
void	dma_set_addresses (const dma_peripheral_t dma, const uint8_t stream, const uint32_t PA, const uint32_t M0A, const uint32_t M1A)
	Set the DMA source and destination addresses.
void	dma_configure_data (const dma_peripheral_t dma, const uint8_t stream, const uint16_t count, const dma_datasize_t msize, const dma_datasize_t psize)
	Set DMA transfers to specified configuration.
void	dma_set_direction (const dma_peripheral_t dma, const uint8_t stream, const dma_dir_t direction)
	Set DMA transfers to the desired direction.
void	dma_configure_stream (const dma_peripheral_t dma, const uint8_t stream, const struct DMAStreamConfig config)
	Set DMA stream to the specified configuration.
void	dma_set_channel (const dma_peripheral_t dma, const uint8_t stream, const uint8_t channel, const dma_priority_t priority)
	Set the DMA stream channel and priority.
void	dma_set_interrupts (const dma_peripheral_t dma, const uint8_t stream, const struct DMAStreamISR config)
	Enabled the specified DMA stream interrupts.
void	dma_enable (const dma_peripheral_t dma, const uint8_t stream)
	Enables DMA stream transfers.
void	dma_disable (const dma_peripheral_t dma, const uint8_t stream)
	Disables DMA stream transfers.

Detailed Description

Function prototypes for the DMA driver.

This file contains all of the enums, macros, and function prototypes required for a functional DMA driver.

DISCLAIMER: No burst or FIFO for the time being!

Author

Vasileios Ch. (BillisC)

Bug

There is a case where DMA1 clears EN SxCR bit when the peripheral address is USART2 DR. There is no workaround at the moment (is it errata?).

Macro Definition Documentation

DMA

#define DMA

(

x

)

Value:

(struct DMARegs *)(DMA1_BASE + (x * 0x400UL))

Function Documentation

dma_configure_data()

void dma_configure_data	(	const dma_peripheral_t	dma,
		const uint8_t	stream,
		const uint16_t	count,
		const dma_datasize_t	msize,
		const dma_datasize_t	psize )

Set DMA transfers to specified configuration.

The DMA datasizes are specified in the dma_datasize_t enum. Any other value will be ignored.

Parameters

dma	The selected DMA
stream	The selected stream (0..7)
count	The total number of data items
msize	The size of data stored in memory
psize	The size of data stored in the peripheral

Returns

None

dma_configure_stream()

void dma_configure_stream	(	const dma_peripheral_t	dma,
		const uint8_t	stream,
		const struct DMAStreamConfig	config )

Set DMA stream to the specified configuration.

The DMA stream options are specified in the DMAStreamConfig struct.

Parameters

dma	The selected DMA
stream	The selected stream (0..7)
config	The stream configuration

Returns

None

dma_disable()

void dma_disable	(	const dma_peripheral_t	dma,
		const uint8_t	stream )

Disables DMA stream transfers.

Parameters

dma	The selected DMA
stream	The selected stream (0..7)

Returns

None

dma_enable()

void dma_enable	(	const dma_peripheral_t	dma,
		const uint8_t	stream )

Enables DMA stream transfers.

Parameters

dma	The selected DMA
stream	The selected stream (0..7)

Returns

None

dma_set_addresses()

void dma_set_addresses	(	const dma_peripheral_t	dma,
		const uint8_t	stream,
		const uint32_t	PA,
		const uint32_t	M0A,
		const uint32_t	M1A )

Set the DMA source and destination addresses.

Usually only the peripheral and M0 addresses are needed. In that case you shall set M1A to zero.

Parameters

dma	The selected DMA
stream	The selected stream (0..7)
PA	The peripheral address
M0A	The memory 0 address
M1A	The memory 1 address

Returns

None

dma_set_channel()

void dma_set_channel	(	const dma_peripheral_t	dma,
		const uint8_t	stream,
		const uint8_t	channel,
		const dma_priority_t	priority )

Set the DMA stream channel and priority.

The DMA priority levels are specified in the dma_priority_t enum. Any other value will be ignored. Refer to the chip's manual for the channel function matrix.

Parameters

dma	The selected DMA
stream	The selected stream (0..7)
channel	The selected channel (0..7)
priority	The stream priority level

Returns

None

dma_set_direction()

void dma_set_direction	(	const dma_peripheral_t	dma,
		const uint8_t	stream,
		const dma_dir_t	direction )

Set DMA transfers to the desired direction.

The DMA directions are specified in the dma_dir_t enum. Any other value will be ignored. After that set the addresses according to the chip's manual.

Parameters

dma	The selected DMA
stream	The selected stream (0..7)
direction	The transfer direction

Returns

None

dma_set_interrupts()

void dma_set_interrupts	(	const dma_peripheral_t	dma,
		const uint8_t	stream,
		const struct DMAStreamISR	config )

Enabled the specified DMA stream interrupts.

The available DMA interrupts are located in the DMAStreamISR struct.

Parameters

dma	The selected DMA
stream	The selected stream (0..7)
config	The interrupt configuration

Returns

None