Transfer Interface

Interface for data transfer functions. More...

Data Structures
struct	transfer_properties_t
struct	transfer_info_t
struct	transfer_callback_args_t
struct	transfer_cfg_t
struct	transfer_api_t
struct	transfer_instance_t

Typedefs
typedef void	transfer_ctrl_t

Enumerations
enum	transfer_mode_t { TRANSFER_MODE_NORMAL = 0, TRANSFER_MODE_REPEAT = 1, TRANSFER_MODE_BLOCK = 2 }
enum	transfer_size_t { TRANSFER_SIZE_1_BYTE = 0, TRANSFER_SIZE_2_BYTE = 1, TRANSFER_SIZE_4_BYTE = 2 }
enum	transfer_addr_mode_t { TRANSFER_ADDR_MODE_FIXED = 0, TRANSFER_ADDR_MODE_OFFSET = 1, TRANSFER_ADDR_MODE_INCREMENTED = 2, TRANSFER_ADDR_MODE_DECREMENTED = 3 }
enum	transfer_repeat_area_t { TRANSFER_REPEAT_AREA_DESTINATION = 0, TRANSFER_REPEAT_AREA_SOURCE = 1 }
enum	transfer_chain_mode_t { TRANSFER_CHAIN_MODE_DISABLED = 0, TRANSFER_CHAIN_MODE_EACH = 2, TRANSFER_CHAIN_MODE_END = 3 }
enum	transfer_irq_t { TRANSFER_IRQ_END = 0, TRANSFER_IRQ_EACH = 1 }
enum	transfer_start_mode_t { TRANSFER_START_MODE_SINGLE = 0, TRANSFER_START_MODE_REPEAT = 1 }

Detailed Description

Interface for data transfer functions.

Summary

The transfer interface supports background data transfer (no CPU intervention).

The transfer interface can be implemented by:

• DTC
• DMAC

Related SSP architecture topics:

• SSP Interfaces
• SSP Predefined Layers
• Using SSP Modules

Transfer Interface description: Transfer Driver on r_dtc and Transfer Driver on r_dmac

Typedef Documentation

transfer_ctrl_t

typedef void transfer_ctrl_t

Transfer control block. Allocate an instance specific control block to pass into the transfer API calls.

Implemented as

• dtc_instance_ctrl_t
• dmac_instance_ctrl_t

Enumeration Type Documentation

transfer_addr_mode_t

enum transfer_addr_mode_t

Address mode specifies whether to modify (increment or decrement) pointer after each transfer.

Enumerator
TRANSFER_ADDR_MODE_FIXED	Address pointer remains fixed after each transfer.
TRANSFER_ADDR_MODE_OFFSET	Address pointer changes as per the configured value of offset_byte.
TRANSFER_ADDR_MODE_INCREMENTED	Address pointer is incremented by associated transfer_size_t after each transfer.
TRANSFER_ADDR_MODE_DECREMENTED	Address pointer is decremented by associated transfer_size_t after each transfer.

transfer_chain_mode_t

enum transfer_chain_mode_t

Chain transfer mode options.

Note

Only applies for DTC.

Enumerator
TRANSFER_CHAIN_MODE_DISABLED	Chain mode not used.
TRANSFER_CHAIN_MODE_EACH	Switch to next transfer after a single transfer from this transfer_info_t.
TRANSFER_CHAIN_MODE_END	Complete the entire transfer defined in this transfer_info_t before chaining to next transfer.

transfer_irq_t

enum transfer_irq_t

Interrupt options.

Enumerator
TRANSFER_IRQ_END	Interrupt occurs only after last transfer. If this transfer is chained to a subsequent transfer, the interrupt will occur only after subsequent chained transfer(s) are complete. Warning DTC triggers the interrupt of the activation source. Choosing TRANSFER_IRQ_END with DTC will prevent activation source interrupts until the transfer is complete.
TRANSFER_IRQ_EACH	Interrupt occurs after each transfer. Note Not available in all HAL drivers. See HAL driver for details. Warning This will prevent chained transfers that would have happened after this one until the next activation source.

transfer_mode_t

enum transfer_mode_t

Transfer mode describes what will happen when a transfer request occurs.

Enumerator
TRANSFER_MODE_NORMAL	In normal mode, each transfer request causes a transfer of transfer_size_t from the source pointer to the destination pointer. The transfer length is decremented and the source and address pointers are updated according to transfer_addr_mode_t. After the transfer length reaches 0, transfer requests will not cause any further transfers.
TRANSFER_MODE_REPEAT	Repeat mode is like normal mode, except that when the transfer length reaches 0, the pointer to the repeat area and the transfer length will be reset to their initial values. If DMAC is used, the transfer repeats only transfer_info_t::num_blocks times. After the transfer repeats transfer_info_t::num_blocks times, transfer requests will not cause any further transfers. If DTC is used, the transfer repeats continuously (no limit to the number of repeat transfers).
TRANSFER_MODE_BLOCK	In block mode, each transfer request causes transfer_info_t::length transfers of transfer_size_t. After each individual transfer, the source and destination pointers are updated according to transfer_addr_mode_t. After the block transfer is complete, transfer_info_t::num_blocks is decremented. After the transfer_info_t::num_blocks reaches 0, transfer requests will not cause any further transfers.

transfer_repeat_area_t

enum transfer_repeat_area_t

Repeat area options (source or destination). In TRANSFER_MODE_REPEAT, the selected pointer returns to its original value after transfer_info_t::length transfers. In TRANSFER_MODE_BLOCK, the selected pointer returns to its original value after each transfer.

Enumerator
TRANSFER_REPEAT_AREA_DESTINATION	Destination area repeated in TRANSFER_MODE_REPEAT or TRANSFER_MODE_BLOCK.
TRANSFER_REPEAT_AREA_SOURCE	Source area repeated in TRANSFER_MODE_REPEAT or TRANSFER_MODE_BLOCK.

transfer_size_t

enum transfer_size_t

Transfer size specifies the size of each individual transfer. Total transfer length = transfer_size_t * transfer_length_t

Enumerator
TRANSFER_SIZE_1_BYTE	Each transfer transfers an 8-bit value.
TRANSFER_SIZE_2_BYTE	Address pointer is incremented after each transfer.
TRANSFER_SIZE_4_BYTE	Address pointer is incremented after each transfer.

transfer_start_mode_t

enum transfer_start_mode_t

Select whether to start single or repeated transfer with software start.

Enumerator
TRANSFER_START_MODE_SINGLE	Software start triggers single transfer.
TRANSFER_START_MODE_REPEAT	Software start transfer continues until transfer is complete.