Introduction

The EnDAT3 API module provides functions for initializing and communicating with EnDAT3-compatible encoders. It supports both host-triggered and periodic communication, and provides interfaces for command transmission and response parsing.

Parameter Validation Strategy

The EnDAT3 driver implements following parameter validation approach:

Initialization-time validation: During endat3_init, all configuration parameters are thoroughly validated including: handle, attrs (configuration structure), params (including pruicss_handle), and all their member fields. This ensures the driver is properly initialized with valid configuration before any operations begin.
Runtime validation: All public APIs validate the handle parameter and internal structure pointers (priv, endat3_interface, attrs, pruicss_handle) for NULL before dereferencing to prevent undefined behavior.
Array bounds checking: All array accesses include explicit bounds checking to prevent buffer overruns. Array indices are validated before use, and array sizes are checked against defined limits.

Typical Usage Flow

The following sequence demonstrates typical usage of the EnDAT3 driver:

1. Initialization:

Call endat3_params_init() to initialize parameters structure
Configure params.pruicss_handle with PRU-ICSS instance from PRUICSS_open()
Call endat3_init() to initialize the driver and hardware

2. Operating Mode Configuration:

Default operating mode is HOST_TRIGGER
Can change operating mode with endat3_set_operating_mode() (HOST_TRIGGER or PERIODIC)
For periodic mode, trigger is done automatically by PRU firmware at configured intervals.

3. Command Execution (Host Trigger Mode):

Call endat3_set_expected_tx_frame_count() to specify number of frames
Call endat3_send_command() to prepare command (e.g., ENDAT3_REQ_DATA0)
Call endat3_release_start_trigger() to initiate communication
Wait for encoder processing (use endat3_is_busy() to poll status)
Call endat3_receive_response() to fetch and validate response
Check return value == ENDAT3_SUCCESS before reading data

4. Data Retrieval:

Use endat3_get_hpf_status() to check High Priority Frame status
Use endat3_get_hpf_data() to retrieve position/encoder data
Use endat3_is_hpf_data_valid() to verify data validity
Optionally use endat3_get_lph_status(), endat3_get_lpf_data() for low priority data

5. Error Handling:

Most APIs return ENDAT3_SUCCESS (0) on success or negative error codes on failure (ENDAT3_ERR_*).
Few APIs do not return ENDAT3_SUCCESS or ENDAT3_ERR_* codes. Refer to API documentation for specific details.

6. Cleanup:

Call endat3_deinit() when finished to release resources

Data Structures
struct	endat3_bg_cmd_params
	Background command request parameters. More...

struct	endat3_clock_config
	Structure defining ENDAT3 clock configuration for selected frequency. More...

struct	endat3_params
	EnDAT3 initialization parameters. More...

struct	endat3_attrs
	EnDAT3 attributes (compile-time/SysConfig configuration data) More...

struct	endat3_hpf
	High Priority Frame structure. More...

struct	endat3_lph
	Low Priority Header structure. More...

struct	endat3_lpf
	Low Priority Frame structure. More...

struct	endat3_periodic_trigger_cfg
	Structure defining ENDAT3 periodic trigger configuration. More...

struct	endat3_interface
	EnDAT3 Interface structure. More...

struct	endat3_priv
	EnDAT3 private data structure (runtime state and configuration) More...

struct	endat3_config
	EnDAT3 configuration handle structure. More...

Functions
void	endat3_params_init (endat3_params *params)
	Initialize EnDAT3 parameters with default values. More...

endat3_handle	endat3_init (uint32_t index, const endat3_params *endat3_params)
	Initialize an EnDAT3 instance. More...

void	endat3_deinit (endat3_handle handle)
	De-initialize an EnDAT3 instance. More...

const endat3_attrs *	endat3_get_attrs (endat3_handle handle)
	Get pointer to EnDAT3 attributes structure. More...

endat3_priv *	endat3_get_priv (endat3_handle handle)
	Get pointer to EnDAT3 private data structure. More...

int32_t	endat3_send_command (endat3_handle handle, uint8_t cmd, uint8_t frames)
	Send EnDAT3 command. More...

int32_t	endat3_receive_response (endat3_handle handle)
	Receive EnDAT3 response. More...

const char *	endat3_get_error_description (endat3_error_code error_code)
	Get error description string. More...

const char *	endat3_get_error_action (endat3_error_code error_code)
	Get recommended action for error code. More...

int32_t	endat3_handle_background_command_request (endat3_handle handle, const endat3_bg_cmd_params params, uint8_t mode, const char **acc_level_desc)
	Handle background command request. More...

int32_t	endat3_get_hpf_status (endat3_handle handle, uint8_t *status)
	Get HPF status byte. More...

int32_t	endat3_get_hpf_data (endat3_handle handle, uint8_t *data)
	Get HPF data array. More...

int32_t	endat3_get_hpf_crc (endat3_handle handle, uint8_t *crc)
	Get HPF CRC value. More...

int32_t	endat3_get_hpf_data_64_bit (endat3_handle handle, uint64_t *data)
	Get HPF data as 64-bit value. More...

int32_t	endat3_is_hpf_data_valid (endat3_handle handle, uint8_t *is_valid)
	Check if HPF data is valid. More...

int32_t	endat3_has_hpf_error (endat3_handle handle, uint8_t *has_error)
	Check if HPF has error flag set. More...

int32_t	endat3_has_hpf_warning (endat3_handle handle, uint8_t *has_warning)
	Check if HPF has warning flag set. More...

int32_t	endat3_has_absolute_value (endat3_handle handle, uint8_t *has_absolute)
	Check if absolute value is available. More...

int32_t	endat3_get_lph_status (endat3_handle handle, uint8_t *status)
	Get LPH status byte. More...

int32_t	endat3_get_lph_lpf_count (endat3_handle handle, uint8_t *num_lpf)
	Get number of LPF frames. More...

int32_t	endat3_get_lph_crc (endat3_handle handle, uint8_t *crc)
	Get LPH CRC value. More...

int32_t	endat3_get_lph_state (endat3_handle handle, endat3_lph_status *state)
	Get LPH communication state. More...

int32_t	endat3_has_bg_error (endat3_handle handle, uint8_t *has_error)
	Check if background operation has error. More...

int32_t	endat3_is_bg_busy (endat3_handle handle, uint8_t *is_busy)
	Check if background processor is busy. More...

int32_t	endat3_has_bg_rtx_error (endat3_handle handle, uint8_t *has_error)
	Check if background RTX error occurred. More...

int32_t	endat3_get_lpf_status (endat3_handle handle, uint8_t index, uint8_t *status)
	Get LPF status byte for specific frame. More...

int32_t	endat3_get_lpf_data (endat3_handle handle, uint8_t index, uint8_t *data)
	Get LPF data array for specific frame. More...

int32_t	endat3_get_lpf_crc (endat3_handle handle, uint8_t index, uint8_t *crc)
	Get LPF CRC value for specific frame. More...

int32_t	endat3_get_lpf_fid (endat3_handle handle, uint8_t index, uint8_t *fid)
	Get LPF FID (Frame ID) for specific frame. More...

int32_t	endat3_is_connected (endat3_handle handle, uint8_t *is_connected)
	Get connection status. More...

int32_t	endat3_is_busy (endat3_handle handle, uint8_t *is_busy)
	Get busy status. More...

int32_t	endat3_set_busy (endat3_handle handle, uint8_t busy)
	Set or clear busy status. More...

int32_t	endat3_get_expected_tx_frame_count (endat3_handle handle, uint32_t *count)
	Get expected TX frame count. More...

int32_t	endat3_set_expected_tx_frame_count (endat3_handle handle, uint32_t count)
	Set expected TX frame count. More...

int32_t	endat3_get_propagation_time (endat3_handle handle, uint32_t *prop_time)
	Get propagation time. More...

int32_t	endat3_get_foreground_op_code (endat3_handle handle, uint32_t *opcode)
	Get foreground operation code. More...

int32_t	endat3_set_foreground_op_code (endat3_handle handle, uint32_t opcode)
	Set foreground operation code. More...

int32_t	endat3_get_background_op_code (endat3_handle handle, uint32_t *opcode)
	Get background operation code. More...

int32_t	endat3_set_background_op_code (endat3_handle handle, uint32_t opcode)
	Set background operation code. More...

int32_t	endat3_get_bg_data (endat3_handle handle, uint8_t index, uint32_t *data)
	Get background data word. More...

int32_t	endat3_set_bg_data (endat3_handle handle, uint8_t index, uint32_t data)
	Set background data word. More...

int32_t	endat3_get_all_bg_data (endat3_handle handle, uint32_t *data)
	Get all background data. More...

int32_t	endat3_set_all_bg_data (endat3_handle handle, const uint32_t *data)
	Set all background data. More...

const volatile uint8_t *	endat3_get_rx_buffer (endat3_handle handle)
	Get RX buffer pointer. More...

const volatile uint8_t *	endat3_get_tx_buffer (endat3_handle handle)
	Get TX buffer pointer. More...

int32_t	endat3_set_tx_buffer (endat3_handle handle, const uint8_t *data, uint32_t length)
	Copy data to TX buffer. More...

int32_t	endat3_get_hpf_frame (endat3_handle handle, endat3_hpf *hpf)
	Get complete HPF structure. More...

int32_t	endat3_get_lph_frame (endat3_handle handle, endat3_lph *lph)
	Get complete LPH structure. More...

int32_t	endat3_get_lpf_frame (endat3_handle handle, uint8_t index, endat3_lpf *lpf)
	Get complete LPF structure. More...

int32_t	endat3_get_error_code (endat3_handle handle, endat3_error_code *error_code)
	Extract error code from HPF or LPF. More...

endat3_interface *	endat3_get_interface (endat3_handle handle)
	Get interface pointer (advanced use) More...

int32_t	endat3_set_operating_mode (endat3_handle handle, uint8_t opmode)
	Set operating mode (host trigger or periodic trigger) More...

int32_t	endat3_get_operating_mode (endat3_handle handle, uint8_t *opmode)
	Get current operating mode. More...

int32_t	endat3_config_iep_cap_event (endat3_handle handle, uint8_t event_num)
	Configure IEP CAP event number in PRU DMEM. More...

int32_t	endat3_config_iep_cmp_event (endat3_handle handle, uint8_t event_num)
	Configure IEP CMP event number in PRU DMEM. More...

int32_t	endat3_release_start_trigger (endat3_handle handle)
	Release start trigger to firmware. More...

int32_t	endat3_clear_start_trigger (endat3_handle handle)
	Clear start trigger flag. More...

int32_t	endat3_get_start_trigger_status (endat3_handle handle, uint8_t *trigger_status)
	Get current start trigger status. More...

Typedefs
typedef endat3_config *	endat3_handle
	EnDAT3 Driver Handle. More...

Enumerations
enum	endat3_lph_status { LPH_STATUS_IDLE = 0, LPH_STATUS_RX_START = 1, LPH_STATUS_RX_LAST = 2, LPH_STATUS_BUSY = 3 }
	Low Priority Header status values. More...

enum	endat3_bg_req_opcode { ENDAT3_BGREQ_NOP = 0x01, ENDAT3_BGREQ_READ = 0x02, ENDAT3_BGREQ_WRITE = 0x03, ENDAT3_BGREQ_RECONFIGURE = 0x04, ENDAT3_BGREQ_AUTH = 0x80, ENDAT3_BGREQ_PROTECT = 0x81, ENDAT3_BGREQ_RESERVED = 0x82, ENDAT3_BGREQ_SETPASS = 0x83, ENDAT3_BGREQ_LOCATE = 0x84 }
	EnDAT3 Background Request (BGREQ) OpCodes. More...

enum	endat3_req_code { ENDAT3_REQ_DATA0 = 0x00, ENDAT3_REQ_DATA1 = 0x01, ENDAT3_REQ_DATA2 = 0x02, ENDAT3_REQ_DATA3 = 0x03, ENDAT3_REQ_DATA4 = 0x04, ENDAT3_REQ_DATA5 = 0x05, ENDAT3_REQ_DATA6 = 0x06, ENDAT3_REQ_DATA7 = 0x07, ENDAT3_REQ_DATA = 0x08, ENDAT3_REQ_DATANOP = 0x09, ENDAT3_REQ_RESET = 0x0B, ENDAT3_REQ_CLEAR = 0x0C, ENDAT3_REQ_ECHO = 0x0E, ENDAT3_REQ_RATE = 0x10, ENDAT3_REQ_HELLO = 0x22, ENDAT3_REQ_RESERVED = 0x40, ENDAT3_REQ_BUSBC = 0x80, ENDAT3_REQ_BUSP2P = 0x81, ENDAT3_REQ_BUSINIT = 0x82, ENDAT3_REQ_FORCE = 0x90 }
	EnDAT3 Foreground Request (REQ.CODE) OpCodes. More...

enum	endat3_menu_option { ENDAT3_MENU_DATA0 = 1, ENDAT3_MENU_DATA1, ENDAT3_MENU_DATA2, ENDAT3_MENU_DATA3, ENDAT3_MENU_DATA4, ENDAT3_MENU_DATA5, ENDAT3_MENU_DATA6, ENDAT3_MENU_DATA7, ENDAT3_MENU_DATA, ENDAT3_MENU_DATANOP, ENDAT3_MENU_RESET, ENDAT3_MENU_CLEAR, ENDAT3_MENU_ECHO, ENDAT3_MENU_RATE, ENDAT3_MENU_HELLO, ENDAT3_MENU_RESERVED, ENDAT3_MENU_BUSBC, ENDAT3_MENU_BUSP2P, ENDAT3_MENU_BUSINIT, ENDAT3_MENU_FORCE }
	EnDAT3 Menu Options. More...

enum	endat3_hpf_status_bits { ENDAT3_HPF_STATUS_F = 0x01, ENDAT3_HPF_STATUS_W = 0x02, ENDAT3_HPF_STATUS_HPFV = 0x04, ENDAT3_HPF_STATUS_RM = 0x08, ENDAT3_HPF_STATUS_ERR_REQ = 0x10 }
	HPF STATUS bits. More...

enum	endat3_lph_status_flags { ENDAT3_LPH_STATUS_IDLE = 0x0, ENDAT3_LPH_STATUS_RX_START = 0x1, ENDAT3_LPH_STATUS_RX_LAST = 0x2, ENDAT3_LPH_STATUS_BUSY = 0x3, ENDAT3_LPH_BG_ERR_EXEC = 0x4, ENDAT3_LPH_BG_BUSY = 0x8, ENDAT3_LPH_BG_RTX_ERROR = 0x10, ENDAT3_LPH_STATE_MASK = 0x3 }
	LPH Status Flags. More...

enum	endat3_error_code { ENDAT3_ERR_UNKNOWN = 0x0000, ENDAT3_FGERR_RECONFIGURE = 0x0001, ENDAT3_FGERR_ECHO = 0x0002, ENDAT3_FGERR_INVALID_FID = 0x0100, ENDAT3_FGERR_DUPLICATE_FID = 0x0101, ENDAT3_FGERR_INVALID_DATA = 0x0200, ENDAT3_FGERR_INT_TRM = 0x0201, ENDAT3_FGERR_NO_SENSOR_DATA = 0x0300, ENDAT3_BGERR_USAGE = 0x1100, ENDAT3_BGERR_USAGE_OPCODE = 0x1101, ENDAT3_BGERR_USAGE_ARGUMENTS = 0x1102, ENDAT3_BGERR_USAGE_SEQUENCE = 0x1103, ENDAT3_BGERR_USAGE_ACCESS_DENIED = 0x1104, ENDAT3_BGERR_USAGE_MEM_ADDRESS = 0x1105, ENDAT3_BGERR_USAGE_NO_BG = 0x1106, ENDAT3_BGERR_INTERNAL = 0x1200, ENDAT3_BGERR_INTERNAL_MEMORY = 0x1201, ENDAT3_BGERR_INTERNAL_CONFIG = 0x1202 }
	EnDat3 Error Codes. More...

Macros
#define	ENDAT3_OPMODE_PERIODIC_CMP (0x0U)
	EnDat3 Operation Mode: Periodic trigger with CMP event. More...

#define	ENDAT3_OPMODE_HOST_TRIGGER (0x1U)
	EnDat3 Operation Mode: Host trigger. More...

#define	ENDAT3_OPMODE_PERIODIC_CAP (0x2U)
	EnDat3 Operation Mode: Periodic trigger with CAP event. More...

#define	ENDAT3_SUCCESS (0)

#define	ENDAT3_ERR_INVALID_INPUT (-1)

#define	ENDAT3_ERR_BUSY (-2)

#define	ENDAT3_ERR_RX_FAIL (-3)

#define	ENDAT3_ERR_LPH_CRC_FAIL (-4)

#define	ENDAT3_ERR_HPF_CRC_FAIL (-5)

#define	ENDAT3_ERR_LPF_CRC_FAIL (-6)

#define	ENDAT3_ERR_SAMPLING_ERROR (-7)

#define	ENDAT3_ERR_INVALID_OPMODE (-8)

#define	ENCODER_IDLE (0x0)

#define	ENCODER_BUSY (0x1)

#define	ENCODER_ERROR (0x2)

#define	ENDAT3_FRAME_SIZE_BYTES (4U)

#define	ENDAT3_CHANNEL_MASK_MAX (0x7U)

#define	ENDAT3_MAX_BG_CMD_INDEX (3U)

#define	ENDAT3_CORE_CLK_200MHZ (200000000U)

#define	ENDAT3_CORE_CLK_300MHZ (300000000U)

#define	REFERENCE_PRU_FREQ_HZ (1000000ULL)
	Reference frequency for delay calculations (1 MHz) More...

#define	REFERENCE_PRU_FREQ_HZ_FOR_SAMPLING (5000000ULL)
	5 MHz reference for sampling delay (gives 60 cycles @ 300MHz, 40 cycles @ 200MHz) More...

#define	ENDAT3_BAUD_RATE_12_5_MBPS (0U)

#define	ENDAT3_BAUD_RATE_25_MBPS (1U)

#define	ENDAT3_OVERSAMPLE_RATE_8X (8U)

#define	ENDAT3_SB_POLARITY (0U)

#define	ENDAT3_TX_CLOCK_MULTIPLIER (2U)

#define	ENDAT3_HPF_TOTAL_SIZE (8)

#define	ENDAT3_LPH_TOTAL_SIZE (4)

#define	ENDAT3_LPF_TOTAL_SIZE (8)

#define	ENDAT3_HPF_OFFSET (0)

#define	ENDAT3_LPH_OFFSET (8)

#define	ENDAT3_LPF_OFFSET (12)

#define	ENDAT3_MIN_RX_BUFFER_SIZE (20)

#define	ENDAT3_RESET_HARD (0x01)

#define	ENDAT3_RESET_SOFT (0x00)

#define	ENDAT3_CLEAR_F (0x01)

#define	ENDAT3_CLEAR_W (0x02)

#define	ENDAT3_CLEAR_REF (0x04)

#define	ENDAT3_RATE_12_5MBPS (0x00)

#define	ENDAT3_RATE_25MBPS (0x01)

#define	ENDAT3_BUSINIT_RESET_ADDR (0x01)

#define	ENDAT3_BUSINIT_KEEP_ADDR (0x00)

#define	ENDAT3_PROTECT_QUERY (0x01)

#define	ENDAT3_PROTECT_SET_READ (0x02)

#define	ENDAT3_PROTECT_SET_WRITE (0x03)

#define	ENDAT3_PASSWORD_HIGH_MASK (0xFFFF0000)

#define	ENDAT3_PASSWORD_LOW_MASK (0x0000FFFF)

#define	ENDAT3_PASSWORD_HIGH_SHIFT (16)

#define	ENDAT3_PRE_LENGTH (25)

#define	ENDAT3_POST_LENGTH (4)

EnDat3 PRU Operating Modes
#define	ENDAT3_MODE_SINGLE_CHANNEL_SINGLE_PRU (0U)
	Single channel, single PRU mode (non-load-share) More...

#define	ENDAT3_TX_START_DELAY_1_REF_CYCLES (218U)

#define	ENDAT3_TX_START_DELAY_2_REF_CYCLES (1748U)

#define	ENDAT3_TX_START_DELAY_3_REF_CYCLES (438U)

#define	ENDAT3_DELAY_10MS_REF_CYCLES (10486U)

#define	ENDAT3_BAUD_RATE_12_5_MBPS_VALUE (12500000U)

#define	ENDAT3_BAUD_RATE_25_MBPS_VALUE (25000000U)

#define	ENDAT3_IEP_MAX_CAP_EVENT (0x8U)

#define	ENDAT3_IEP_MAX_CMP_EVENT (0x10U)

#define	ENDAT3_CFG_REG_SIZE (4U)

#define	ENDAT3_CSL_ICSS_PR1_IEP0_SLV_CAP0_REG0 (CSL_ICSS_PR1_IEP0_SLV_CAP_CFG_REG + 2U*ENDAT3_CFG_REG_SIZE)

#define	ENDAT3_8_BYTE_REG_OFFSET (8U)

#define	HPF_DATA_SIZE (6)

#define	LPF_DATA_SIZE (6)

#define	MAX_LPF_COUNT (8)

#define	LUT_SIZE (64)

#define	RX_BUFFER_SIZE (64)

#define	TX_BUFFER_SIZE (24)

#define	BG_DATA_SIZE (6)

Macro Definition Documentation

◆ ENDAT3_MODE_SINGLE_CHANNEL_SINGLE_PRU

#define ENDAT3_MODE_SINGLE_CHANNEL_SINGLE_PRU (0U)

Single channel, single PRU mode (non-load-share)

◆ ENDAT3_OPMODE_PERIODIC_CMP

#define ENDAT3_OPMODE_PERIODIC_CMP (0x0U)

EnDat3 Operation Mode: Periodic trigger with CMP event.

In periodic CMP mode, the PRU firmware automatically triggers position readout at regular intervals using IEP CMP (Compare) events.

◆ ENDAT3_OPMODE_HOST_TRIGGER

#define ENDAT3_OPMODE_HOST_TRIGGER (0x1U)

EnDat3 Operation Mode: Host trigger.

In host trigger mode, the R5F host processor explicitly triggers each position readout by setting the trigger bit.

◆ ENDAT3_OPMODE_PERIODIC_CAP

#define ENDAT3_OPMODE_PERIODIC_CAP (0x2U)

EnDat3 Operation Mode: Periodic trigger with CAP event.

In periodic CAP mode, the PRU firmware automatically triggers position readout at regular intervals using IEP CAP (Capture) events.

◆ ENDAT3_SUCCESS

#define ENDAT3_SUCCESS (0)

Success code

◆ ENDAT3_ERR_INVALID_INPUT

#define ENDAT3_ERR_INVALID_INPUT (-1)

Invalid input parameter (NULL pointer, invalid value, out of bounds)

◆ ENDAT3_ERR_BUSY

#define ENDAT3_ERR_BUSY (-2)

Encoder busy (transfer in progress)

◆ ENDAT3_ERR_RX_FAIL

#define ENDAT3_ERR_RX_FAIL (-3)

Reception failure

◆ ENDAT3_ERR_LPH_CRC_FAIL

#define ENDAT3_ERR_LPH_CRC_FAIL (-4)

LPH (Low Priority Header) CRC mismatch

◆ ENDAT3_ERR_HPF_CRC_FAIL

#define ENDAT3_ERR_HPF_CRC_FAIL (-5)

HPF (High Priority Frame) CRC mismatch

◆ ENDAT3_ERR_LPF_CRC_FAIL

#define ENDAT3_ERR_LPF_CRC_FAIL (-6)

LPF (Low Priority Frame) CRC mismatch

◆ ENDAT3_ERR_SAMPLING_ERROR

#define ENDAT3_ERR_SAMPLING_ERROR (-7)

Encoder sampling/timing error

◆ ENDAT3_ERR_INVALID_OPMODE

#define ENDAT3_ERR_INVALID_OPMODE (-8)

Invalid operating mode (mode > 2)

◆ ENCODER_IDLE

#define ENCODER_IDLE (0x0)

Encoder idle, ready for communication

◆ ENCODER_BUSY

#define ENCODER_BUSY (0x1)

Encoder busy, transfer in progress

◆ ENCODER_ERROR

#define ENCODER_ERROR (0x2)

Encoder error detected during transfer

◆ ENDAT3_FRAME_SIZE_BYTES

#define ENDAT3_FRAME_SIZE_BYTES (4U)

EnDAT3 frame size in bytes

◆ ENDAT3_CHANNEL_MASK_MAX

#define ENDAT3_CHANNEL_MASK_MAX (0x7U)

Maximum valid channel mask (ch0|ch1|ch2)

◆ ENDAT3_MAX_BG_CMD_INDEX

#define ENDAT3_MAX_BG_CMD_INDEX (3U)

Exclusive upper bound for background command index (valid range: 0-2)

◆ ENDAT3_CORE_CLK_200MHZ

#define ENDAT3_CORE_CLK_200MHZ (200000000U)

200 MHz core clock frequency

◆ ENDAT3_CORE_CLK_300MHZ

#define ENDAT3_CORE_CLK_300MHZ (300000000U)

300 MHz core clock frequency

◆ REFERENCE_PRU_FREQ_HZ

#define REFERENCE_PRU_FREQ_HZ (1000000ULL)

Reference frequency for delay calculations (1 MHz)

◆ REFERENCE_PRU_FREQ_HZ_FOR_SAMPLING

#define REFERENCE_PRU_FREQ_HZ_FOR_SAMPLING (5000000ULL)

5 MHz reference for sampling delay (gives 60 cycles @ 300MHz, 40 cycles @ 200MHz)

◆ ENDAT3_TX_START_DELAY_1_REF_CYCLES

#define ENDAT3_TX_START_DELAY_1_REF_CYCLES (218U)

These values are derived from the original 300 MHz PRU frequency implementation and are scaled to actual PRU frequency at runtime using the formula: actual_cycles = (reference_cycles * actual_freq) / REFERENCE_PRU_FREQ_HZ TX start delay 1 reference (65535 / 300)

◆ ENDAT3_TX_START_DELAY_2_REF_CYCLES

#define ENDAT3_TX_START_DELAY_2_REF_CYCLES (1748U)

TX start delay 2 reference (524288 / 300)

◆ ENDAT3_TX_START_DELAY_3_REF_CYCLES

#define ENDAT3_TX_START_DELAY_3_REF_CYCLES (438U)

TX start delay 3 reference (131328 / 300)

◆ ENDAT3_DELAY_10MS_REF_CYCLES

#define ENDAT3_DELAY_10MS_REF_CYCLES (10486U)

10ms delay reference (3145728 / 300)

◆ ENDAT3_BAUD_RATE_12_5_MBPS

#define ENDAT3_BAUD_RATE_12_5_MBPS (0U)

12.5 Mbps mode selector

◆ ENDAT3_BAUD_RATE_25_MBPS

#define ENDAT3_BAUD_RATE_25_MBPS (1U)

25 Mbps mode selector

◆ ENDAT3_BAUD_RATE_12_5_MBPS_VALUE

#define ENDAT3_BAUD_RATE_12_5_MBPS_VALUE (12500000U)

Clock configuration constants 12.5 Mbps baud rate value in Hz

◆ ENDAT3_BAUD_RATE_25_MBPS_VALUE

#define ENDAT3_BAUD_RATE_25_MBPS_VALUE (25000000U)

25 Mbps baud rate value in Hz

◆ ENDAT3_IEP_MAX_CAP_EVENT

#define ENDAT3_IEP_MAX_CAP_EVENT (0x8U)

IEP (Industrial Ethernet Peripheral) event limits for periodic trigger mode Maximum IEP CAP events (0-7)

◆ ENDAT3_IEP_MAX_CMP_EVENT

#define ENDAT3_IEP_MAX_CMP_EVENT (0x10U)

Maximum IEP CMP events (0-15)

◆ ENDAT3_CFG_REG_SIZE

#define ENDAT3_CFG_REG_SIZE (4U)

IEP register offsets for periodic trigger mode IEP configuration register size in bytes

◆ ENDAT3_CSL_ICSS_PR1_IEP0_SLV_CAP0_REG0

#define ENDAT3_CSL_ICSS_PR1_IEP0_SLV_CAP0_REG0 (CSL_ICSS_PR1_IEP0_SLV_CAP_CFG_REG + 2U*ENDAT3_CFG_REG_SIZE)

IEP CAP0 register 0 offset

◆ ENDAT3_8_BYTE_REG_OFFSET

#define ENDAT3_8_BYTE_REG_OFFSET (8U)

8-byte register offset for IEP CMP/CAP registers

◆ ENDAT3_OVERSAMPLE_RATE_8X

#define ENDAT3_OVERSAMPLE_RATE_8X (8U)

8x oversampling rate for RX clock

◆ ENDAT3_SB_POLARITY

#define ENDAT3_SB_POLARITY (0U)

Start bit polarity configuration

◆ ENDAT3_TX_CLOCK_MULTIPLIER

#define ENDAT3_TX_CLOCK_MULTIPLIER (2U)

TX clock multiplier: TX clock = 2x baud rate

◆ HPF_DATA_SIZE

#define HPF_DATA_SIZE (6)

Buffer and data size definitions High Priority Frame data size in bytes

◆ LPF_DATA_SIZE

#define LPF_DATA_SIZE (6)

Low Priority Frame data size in bytes

◆ MAX_LPF_COUNT

#define MAX_LPF_COUNT (8)

Maximum number of LPF frames

◆ LUT_SIZE

#define LUT_SIZE (64)

Lookup table size (256 bytes / 4 bytes per uint32_t)

◆ RX_BUFFER_SIZE

#define RX_BUFFER_SIZE (64)

Receive buffer size

◆ TX_BUFFER_SIZE

#define TX_BUFFER_SIZE (24)

Transmit buffer size

◆ BG_DATA_SIZE

#define BG_DATA_SIZE (6)

Background data array size

◆ ENDAT3_HPF_TOTAL_SIZE

#define ENDAT3_HPF_TOTAL_SIZE (8)

HPF total frame size: 6 data + 1 status + 1 CRC

◆ ENDAT3_LPH_TOTAL_SIZE

#define ENDAT3_LPH_TOTAL_SIZE (4)

LPH total frame size: 2 data + 1 status + 1 CRC

◆ ENDAT3_LPF_TOTAL_SIZE

#define ENDAT3_LPF_TOTAL_SIZE (8)

LPF total frame size: 6 data + 1 FID/status + 1 CRC

◆ ENDAT3_HPF_OFFSET

#define ENDAT3_HPF_OFFSET (0)

HPF offset in RX buffer

◆ ENDAT3_LPH_OFFSET

#define ENDAT3_LPH_OFFSET (8)

LPH offset in RX buffer (after HPF)

◆ ENDAT3_LPF_OFFSET

#define ENDAT3_LPF_OFFSET (12)

LPF offset in RX buffer (after HPF + LPH)

◆ ENDAT3_MIN_RX_BUFFER_SIZE

#define ENDAT3_MIN_RX_BUFFER_SIZE (20)

Minimum RX buffer size: HPF(8) + LPH(4) + LPF(8)

◆ ENDAT3_RESET_HARD

#define ENDAT3_RESET_HARD (0x01)

Hard reset command data

◆ ENDAT3_RESET_SOFT

#define ENDAT3_RESET_SOFT (0x00)

Soft reset command data

◆ ENDAT3_CLEAR_F

#define ENDAT3_CLEAR_F (0x01)

Clear F (error) flag

◆ ENDAT3_CLEAR_W

#define ENDAT3_CLEAR_W (0x02)

Clear W (warning) flag

◆ ENDAT3_CLEAR_REF

#define ENDAT3_CLEAR_REF (0x04)

Clear reference flag

◆ ENDAT3_RATE_12_5MBPS

#define ENDAT3_RATE_12_5MBPS (0x00)

12.5 Mbps data rate

◆ ENDAT3_RATE_25MBPS

#define ENDAT3_RATE_25MBPS (0x01)

25 Mbps data rate

◆ ENDAT3_BUSINIT_RESET_ADDR

#define ENDAT3_BUSINIT_RESET_ADDR (0x01)

Bus init with address reset

◆ ENDAT3_BUSINIT_KEEP_ADDR

#define ENDAT3_BUSINIT_KEEP_ADDR (0x00)

Bus init keeping addresses

◆ ENDAT3_PROTECT_QUERY

#define ENDAT3_PROTECT_QUERY (0x01)

Query current access levels

◆ ENDAT3_PROTECT_SET_READ

#define ENDAT3_PROTECT_SET_READ (0x02)

Set access level for read operations

◆ ENDAT3_PROTECT_SET_WRITE

#define ENDAT3_PROTECT_SET_WRITE (0x03)

Set access level for write operations

◆ ENDAT3_PASSWORD_HIGH_MASK

#define ENDAT3_PASSWORD_HIGH_MASK (0xFFFF0000)

Upper 16 bits mask

◆ ENDAT3_PASSWORD_LOW_MASK

#define ENDAT3_PASSWORD_LOW_MASK (0x0000FFFF)

Lower 16 bits mask

◆ ENDAT3_PASSWORD_HIGH_SHIFT

#define ENDAT3_PASSWORD_HIGH_SHIFT (16)

Shift for upper 16 bits

◆ ENDAT3_PRE_LENGTH

#define ENDAT3_PRE_LENGTH (25)

Minimum preamble length in halfbits

◆ ENDAT3_POST_LENGTH

#define ENDAT3_POST_LENGTH (4)

Postamble length in halfbits

Typedef Documentation

◆ endat3_handle

typedef endat3_config* endat3_handle

EnDAT3 Driver Handle.

Opaque handle to an EnDAT3 instance. Obtained from endat3_init() and used in all subsequent EnDAT3 API calls.

Enumeration Type Documentation

◆ endat3_lph_status

enum endat3_lph_status

Low Priority Header status values.

Status values that can appear in the LPH status byte.

Enumerator
LPH_STATUS_IDLE	IDLE state
LPH_STATUS_RX_START	RX_START state - beginning of reception
LPH_STATUS_RX_LAST	RX_LAST state - last reception frame
LPH_STATUS_BUSY	BUSY state - processing in progress

◆ endat3_bg_req_opcode

enum endat3_bg_req_opcode

EnDAT3 Background Request (BGREQ) OpCodes.

Operation codes for background processing operations.

Enumerator
ENDAT3_BGREQ_NOP	No operation
ENDAT3_BGREQ_READ	Read from encoder memory
ENDAT3_BGREQ_WRITE	Write to encoder memory
ENDAT3_BGREQ_RECONFIGURE	Reconfigure parameters
ENDAT3_BGREQ_AUTH	Authentication
ENDAT3_BGREQ_PROTECT	Set protection
ENDAT3_BGREQ_RESERVED	Reserved for future use
ENDAT3_BGREQ_SETPASS	Set password
ENDAT3_BGREQ_LOCATE	Locate function

◆ endat3_req_code

enum endat3_req_code

EnDAT3 Foreground Request (REQ.CODE) OpCodes.

Operation codes for foreground request commands.

Enumerator
ENDAT3_REQ_DATA0	Activate LPF send list 0
ENDAT3_REQ_DATA1	Activate LPF send list 1
ENDAT3_REQ_DATA2	Activate LPF send list 2
ENDAT3_REQ_DATA3	Activate LPF send list 3
ENDAT3_REQ_DATA4	Activate LPF send list 4
ENDAT3_REQ_DATA5	Activate LPF send list 5
ENDAT3_REQ_DATA6	Activate LPF send list 6
ENDAT3_REQ_DATA7	Activate LPF send list 7
ENDAT3_REQ_DATA	Data with BGD
ENDAT3_REQ_DATANOP	Data without BGD
ENDAT3_REQ_RESET	Encoder reset
ENDAT3_REQ_CLEAR	Resetting of states
ENDAT3_REQ_ECHO	Echo for measuring propagation time
ENDAT3_REQ_RATE	Set data transfer rate
ENDAT3_REQ_HELLO	Switch to EnDat 3 mode
ENDAT3_REQ_RESERVED	Reserved
ENDAT3_REQ_BUSBC	Bus command for broadcast
ENDAT3_REQ_BUSP2P	Bus command for point-to-point communication
ENDAT3_REQ_BUSINIT	Initialization of a bus setup
ENDAT3_REQ_FORCE	Forced dynamic sampling

◆ endat3_menu_option

enum endat3_menu_option

EnDAT3 Menu Options.

Menu options for user interface commands.

Enumerator
ENDAT3_MENU_DATA0	Start with 1
ENDAT3_MENU_DATA1	DATA1 command
ENDAT3_MENU_DATA2	DATA2 command
ENDAT3_MENU_DATA3	DATA3 command
ENDAT3_MENU_DATA4	DATA4 command
ENDAT3_MENU_DATA5	DATA5 command
ENDAT3_MENU_DATA6	DATA6 command
ENDAT3_MENU_DATA7	DATA7 command
ENDAT3_MENU_DATA	DATA command
ENDAT3_MENU_DATANOP	DATANOP command
ENDAT3_MENU_RESET	RESET command
ENDAT3_MENU_CLEAR	CLEAR command
ENDAT3_MENU_ECHO	ECHO command
ENDAT3_MENU_RATE	RATE command
ENDAT3_MENU_HELLO	HELLO command
ENDAT3_MENU_RESERVED	RESERVED command
ENDAT3_MENU_BUSBC	BUSBC command
ENDAT3_MENU_BUSP2P	BUSP2P command
ENDAT3_MENU_BUSINIT	BUSINIT command
ENDAT3_MENU_FORCE	FORCE command

◆ endat3_hpf_status_bits

enum endat3_hpf_status_bits

HPF STATUS bits.

Individual bits in the HPF status byte.

Enumerator
ENDAT3_HPF_STATUS_F	Bit 0: Collective error bit
ENDAT3_HPF_STATUS_W	Bit 1: Collective warning bit
ENDAT3_HPF_STATUS_HPFV	Bit 2: Validity of HPF data
ENDAT3_HPF_STATUS_RM	Bit 3: Availability of absolute value
ENDAT3_HPF_STATUS_ERR_REQ	Bit 4: Request code not supported

◆ endat3_lph_status_flags

enum endat3_lph_status_flags

LPH Status Flags.

Status flags for the Low Priority Header (LPH).

Enumerator
ENDAT3_LPH_STATUS_IDLE	Idle state, no background operation in progress
ENDAT3_LPH_STATUS_RX_START	First frame of a multi-frame background response
ENDAT3_LPH_STATUS_RX_LAST	Last frame of a multi-frame background response
ENDAT3_LPH_STATUS_BUSY	Background operation in progress
ENDAT3_LPH_BG_ERR_EXEC	Error during background operation execution
ENDAT3_LPH_BG_BUSY	Background processor is busy
ENDAT3_LPH_BG_RTX_ERROR	Background transmit/receive error
ENDAT3_LPH_STATE_MASK	Mask for extracting LPH state (bits 0-1)

◆ endat3_error_code

enum endat3_error_code

EnDat3 Error Codes.

Error codes used in foreground and background communication.

Enumerator
ENDAT3_ERR_UNKNOWN	The cause of the error is unknown
ENDAT3_FGERR_RECONFIGURE	Device is in configuration as a result of RECONFIGURE
ENDAT3_FGERR_ECHO	An ECHO is being responded to
ENDAT3_FGERR_INVALID_FID	An invalid FID was configured
ENDAT3_FGERR_DUPLICATE_FID	FID was selected more than once during the cycle
ENDAT3_FGERR_INVALID_DATA	LPF is supported, but invalid data were delivered internally
ENDAT3_FGERR_INT_TRM	LPF is supported but currently unavailable
ENDAT3_FGERR_NO_SENSOR_DATA	Sensor box data not available
ENDAT3_BGERR_USAGE	Generic operator error
ENDAT3_BGERR_USAGE_OPCODE	Invalid or unsupported command code
ENDAT3_BGERR_USAGE_ARGUMENTS	Invalid arguments
ENDAT3_BGERR_USAGE_SEQUENCE	Invalid command sequence
ENDAT3_BGERR_USAGE_ACCESS_DENIED	Access denied; insufficient user level
ENDAT3_BGERR_USAGE_MEM_ADDRESS	Access to invalid address
ENDAT3_BGERR_USAGE_NO_BG	Encoder does not support background processing
ENDAT3_BGERR_INTERNAL	Generic exception error in the encoder
ENDAT3_BGERR_INTERNAL_MEMORY	Exception error when accessing memory
ENDAT3_BGERR_INTERNAL_CONFIG	Exception error: configuration invalid

Function Documentation

◆ endat3_params_init()

void endat3_params_init ( endat3_params * params )

Initialize EnDAT3 parameters with default values.

Populates the endat3_params structure with default values. Must be called before passing params to endat3_init.

Parameters

[out] params Pointer to params structure to initialize

Note: On NULL params, function returns without performing any operation

◆ endat3_init()

endat3_handle endat3_init	(	uint32_t	index,
		const endat3_params *	endat3_params
	)

Initialize an EnDAT3 instance.

Initializes an EnDAT3 driver instance with the specified configuration. This function validates all parameters, sets up the firmware interface, and configures hardware based on both SysConfig attributes and runtime params.

Note: This function internally calls: PRUICSS_setGpMuxSelect(), endat3_config_clr_cfg0(), endat3_calculate_clock(), endat3_config_clock(), endat3_set_delay_cycles(), endat3_set_channel_mask(), endat3_generate_memory_image(), endat3_config_iep_base_address(), endat3_config_iep_cmp_event(), endat3_config_iep_cap_event(), and endat3_set_operating_mode().

Parameters

[in]	index	Index of EnDAT3 (0 to gEndat3ConfigNum - 1)
[in]	endat3_params	Pointer to structure containing EnDAT3 initialization parameters

Return values

handle	Pointer to initialized endat3_handle instance
NULL	On validation failure including: Invalid index (>= gEndat3ConfigNum) NULL params or params->pruicss_handle NULL attrs/priv in config array Invalid attrs fields Only ENDAT3_BAUD_RATE_12_5_MBPS supported (12.5 Mbps) Only 200MHz or 300MHz core_clk_freq supported Hardware initialization failure (PRUICSS_setGpMuxSelect, clock config, etc.)

◆ endat3_deinit()

void endat3_deinit ( endat3_handle handle )

De-initialize an EnDAT3 instance.

De-initializes the EnDAT3 instance by marking the handle as closed (is_open = 0). It does not free memory or disable PRU cores.

Parameters

[in] handle Handle to EnDAT3 instance

Note: On NULL handle, function returns without performing any operation.

◆ endat3_get_attrs()

const endat3_attrs* endat3_get_attrs ( endat3_handle handle )

Get pointer to EnDAT3 attributes structure.

Provides access to the read-only attributes structure containing configuration parameters set during initialization or generated by SysConfig.

Parameters

[in] handle EnDAT3 handle

Return values

attrs	Pointer to const endat3_attrs structure
NULL	If handle is NULL

◆ endat3_get_priv()

endat3_priv* endat3_get_priv ( endat3_handle handle )

Get pointer to EnDAT3 private data structure.

Provides access to the private data structure containing runtime state information.

Parameters

[in] handle EnDAT3 handle

Return values

priv	Pointer to endat3_priv structure
NULL	If handle is NULL

◆ endat3_send_command()

int32_t endat3_send_command	(	endat3_handle	handle,
		uint8_t	cmd,
		uint8_t	frames
	)

Send EnDAT3 command.

Prepares and sends an EnDAT3 command with the specified command code and number of frames. Validates input parameters and checks for buffer overflow conditions before transmission.

Parameters

handle	EnDAT3 handle
cmd	Command code
frames	Number of frames to transmit (1-6, limited by TX_BUFFER_SIZE/4)

Returns: ENDAT3_SUCCESS (0) on success; ENDAT3_ERR_INVALID_INPUT (-1) on error: invalid handle, NULL pointers, buffer overflow, or invalid parameters

Note

CRITICAL: Always check return value before calling endat3_set_busy() or waiting for response

Validation performed:

Handle NULL check
Frame count validation via endat3_prepare_request() (1 to ENDAT3_MAX_TX_FRAMES)
Background data array validation (NULL check)

Internal function used: endat3_prepare_request()

◆ endat3_receive_response()

int32_t endat3_receive_response ( endat3_handle handle )

Receive EnDAT3 response.

Receives and processes EnDAT3 response frames, verifying CRC integrity and parsing the data into appropriate structures.

Parameters

handle EnDAT3 handle

Returns: ENDAT3_SUCCESS (0) on successful reception with valid CRC; ENDAT3_ERR_INVALID_INPUT (-1) if handle or priv is NULL; ENDAT3_ERR_BUSY (-2) if encoder is busy (transfer in progress); ENDAT3_ERR_LPH_CRC_FAIL (-4) on LPH CRC mismatch; ENDAT3_ERR_HPF_CRC_FAIL (-5) on HPF CRC mismatch; ENDAT3_ERR_LPF_CRC_FAIL (-6) on LPF CRC mismatch; ENDAT3_ERR_SAMPLING_ERROR (-7) on encoder sampling/timing error (busy==ENCODER_ERROR)

Note

IMPORTANT: Check return value == ENDAT3_SUCCESS before reading HPF/LPH/LPF data

Validation performed:

Handle NULL check
Busy status checking via endat3_wait_rx_complete()
RX buffer validation (internal)
CRC validation for HPF, LPH, and LPF (when applicable)

◆ endat3_get_error_description()

const char* endat3_get_error_description ( endat3_error_code error_code )

Get error description string.

Returns a human-readable description for the given EnDAT3 error code. Useful for logging and debugging error conditions.

Parameters

error_code The error code to get description for

Returns: Pointer to error description string (never NULL, always returns valid string)

endat3_error_code error;
if(endat3_get_error_code(handle, &error) == ENDAT3_SUCCESS)
{
    const char* desc = endat3_get_error_description(error);
    DebugP_log("Error: %s\r\n", desc);
}

◆ endat3_get_error_action()

const char* endat3_get_error_action ( endat3_error_code error_code )

Get recommended action for error code.

Returns a recommended action string for the given EnDAT3 error code. Helps users understand what to do when an error occurs.

Parameters

error_code The error code to get recommended action for

Returns: Pointer to recommended action string (never NULL, always returns valid string)

endat3_error_code error;
if(endat3_get_error_code(handle, &error) == ENDAT3_SUCCESS)
{
    const char* action = endat3_get_error_action(error);
    DebugP_log("Recommended action: %s\r\n", action);
}

◆ endat3_handle_background_command_request()

int32_t endat3_handle_background_command_request	(	endat3_handle	handle,
		const endat3_bg_cmd_params *	params,
		uint8_t *	mode,
		const char **	acc_level_desc
	)

Handle background command request.

Processes and prepares a background command request for transmission. Handles various background operations like READ, WRITE, AUTH, PROTECT, etc. Formats the command data according to the operation code and parameters.

Parameters

handle	EnDAT3 handle
params	Pointer to background command parameters structure (endat3_bg_cmd_params)
mode	Pointer to store mode value (optional, can be NULL if not needed). Only populated when op_code is ENDAT3_BGREQ_PROTECT and mode is not NULL.
acc_level_desc	Pointer to store access level description string (optional, can be NULL if not needed). Only populated when op_code is ENDAT3_BGREQ_PROTECT and acc_level_desc is not NULL.

Return values

ENDAT3_SUCCESS	(0) on success
ENDAT3_ERR_INVALID_INPUT	(-1) on validation failure (NULL handle, NULL params, or index >= ENDAT3_MAX_BG_CMD_INDEX)

Note

Validation performed:

Handle NULL check
Params pointer NULL check
Index bounds check (index must be 0-2)
Individual parameter members (op_code, addr_msb, addr_lsb, data, frame_cnt) are NOT validated

Output parameters (mode, acc_level_desc) are only meaningful for ENDAT3_BGREQ_PROTECT operation

◆ endat3_get_hpf_status()

int32_t endat3_get_hpf_status	(	endat3_handle	handle,
		uint8_t *	status
	)

Get HPF status byte.

Retrieves the status byte from the High Priority Frame, which contains critical status flags including F, W, HPFV, RM, and ERR_REQ bits.

Parameters

handle	EnDAT3 handle
status	Pointer to store HPF status byte

Returns: ENDAT3_SUCCESS (0) on success, ENDAT3_ERR_INVALID_INPUT (-1) if handle or status is NULL

uint8_t status;
if(endat3_get_hpf_status(handle, &status) == ENDAT3_SUCCESS)
{
    if(status & ENDAT3_HPF_STATUS_F)
{
        // Handle error condition
    }
}

◆ endat3_get_hpf_data()

int32_t endat3_get_hpf_data	(	endat3_handle	handle,
		uint8_t *	data
	)

Get HPF data array.

Retrieves the 6-byte data payload from the High Priority Frame. The data is copied to the provided buffer.

Parameters

handle	EnDAT3 handle
data	Buffer to store HPF data (must be at least 6 bytes)

Returns: Number of bytes copied (6) on success; ENDAT3_ERR_INVALID_INPUT (-1) if handle or data is NULL

Note: On failure (NULL handle or data pointer), returns ENDAT3_ERR_INVALID_INPUT immediately without accessing any memory. Always check return value before using the data buffer.

uint8_t hpf_data[6];
int32_t bytes = endat3_get_hpf_data(handle, hpf_data);
if(bytes == 6)
{
    // Process HPF data
}

◆ endat3_get_hpf_crc()

int32_t endat3_get_hpf_crc	(	endat3_handle	handle,
		uint8_t *	crc
	)

Get HPF CRC value.

Retrieves the CRC checksum from the High Priority Frame.

Parameters

handle	EnDAT3 handle
crc	Pointer to store HPF CRC value

Returns: ENDAT3_SUCCESS (0) on success, ENDAT3_ERR_INVALID_INPUT (-1) if handle or crc is NULL

◆ endat3_get_hpf_data_64_bit()

int32_t endat3_get_hpf_data_64_bit	(	endat3_handle	handle,
		uint64_t *	data
	)

Get HPF data as 64-bit value.

Retrieves the HPF data payload as a single 64-bit unsigned integer. Useful for position data extraction. Data is packed in little-endian format.

Parameters

handle	EnDAT3 handle
data	Pointer to store HPF data as uint64_t

Returns: ENDAT3_SUCCESS (0) on success, ENDAT3_ERR_INVALID_INPUT (-1) if handle or data is NULL

uint64_t position;
if(endat3_get_hpf_data_64_bit(handle, &position) == ENDAT3_SUCCESS)
{
    uint32_t single_turn = position & 0x1FFF;  // Extract 13-bit single turn
}

◆ endat3_is_hpf_data_valid()

int32_t endat3_is_hpf_data_valid	(	endat3_handle	handle,
		uint8_t *	is_valid
	)

Check if HPF data is valid.

Checks the HPFV bit in the HPF status to determine if the data is valid.

Parameters

handle	EnDAT3 handle
is_valid	Pointer to store result (1 if HPF data is valid, 0 otherwise)

Returns: ENDAT3_SUCCESS (0) on success ENDAT3_ERR_INVALID_INPUT (-1) if handle or is_valid is NULL

◆ endat3_has_hpf_error()

int32_t endat3_has_hpf_error	(	endat3_handle	handle,
		uint8_t *	has_error
	)

Check if HPF has error flag set.

Checks the F bit in the HPF status to determine if an error is present.

Parameters

handle	EnDAT3 handle
has_error	Pointer to store result (1 if error flag is set, 0 otherwise)

Returns: ENDAT3_SUCCESS (0) on success ENDAT3_ERR_INVALID_INPUT (-1) if handle or has_error is NULL

◆ endat3_has_hpf_warning()

int32_t endat3_has_hpf_warning	(	endat3_handle	handle,
		uint8_t *	has_warning
	)

Check if HPF has warning flag set.

Checks the W bit in the HPF status to determine if a warning is present.

Parameters

handle	EnDAT3 handle
has_warning	Pointer to store result (1 if warning flag is set, 0 otherwise)

Returns: ENDAT3_SUCCESS (0) on success ENDAT3_ERR_INVALID_INPUT (-1) if handle or has_warning is NULL

◆ endat3_has_absolute_value()

int32_t endat3_has_absolute_value	(	endat3_handle	handle,
		uint8_t *	has_absolute
	)

Check if absolute value is available.

Checks the RM bit in the HPF status to determine if absolute position value is available.

Parameters

handle	EnDAT3 handle
has_absolute	Pointer to store result (1 if absolute value is available, 0 otherwise)

Returns: ENDAT3_SUCCESS (0) on success ENDAT3_ERR_INVALID_INPUT (-1) if handle or has_absolute is NULL

◆ endat3_get_lph_status()

int32_t endat3_get_lph_status	(	endat3_handle	handle,
		uint8_t *	status
	)

Get LPH status byte.

Retrieves the status byte from the Low Priority Header, which contains the communication state and error flags.

Parameters

handle	EnDAT3 handle
status	Pointer to store LPH status byte

Returns: ENDAT3_SUCCESS (0) on success, ENDAT3_ERR_INVALID_INPUT (-1) if handle or status is NULL

◆ endat3_get_lph_lpf_count()

int32_t endat3_get_lph_lpf_count	(	endat3_handle	handle,
		uint8_t *	num_lpf
	)

Get number of LPF frames.

Retrieves the number of Low Priority Frames indicated in the LPH.

Parameters

handle	EnDAT3 handle
num_lpf	Pointer to store number of LPF frames (0 to MAX_LPF_COUNT)

Returns: ENDAT3_SUCCESS (0) on success, ENDAT3_ERR_INVALID_INPUT (-1) if handle or num_lpf is NULL

◆ endat3_get_lph_crc()

int32_t endat3_get_lph_crc	(	endat3_handle	handle,
		uint8_t *	crc
	)

Get LPH CRC value.

Retrieves the CRC checksum from the Low Priority Header.

Parameters

handle	EnDAT3 handle
crc	Pointer to store LPH CRC value

Returns: ENDAT3_SUCCESS (0) on success, ENDAT3_ERR_INVALID_INPUT (-1) if handle or crc is NULL

◆ endat3_get_lph_state()

int32_t endat3_get_lph_state	(	endat3_handle	handle,
		endat3_lph_status *	state
	)

Get LPH communication state.

Extracts the communication state from the LPH status byte (bits 0-1).

Parameters

handle	EnDAT3 handle
state	Pointer to store LPH state (IDLE, RX_START, RX_LAST, BUSY)

Returns: ENDAT3_SUCCESS (0) on success ENDAT3_ERR_INVALID_INPUT (-1) if handle or state is NULL

endat3_lph_status state;
if(endat3_get_lph_state(handle, &state) == ENDAT3_SUCCESS)
{
    switch(state)
    {
        case LPH_STATUS_IDLE:
            // Ready for new command
            break;
        case LPH_STATUS_BUSY:
            // Background operation in progress
            break;
    }
}

◆ endat3_has_bg_error()

int32_t endat3_has_bg_error	(	endat3_handle	handle,
		uint8_t *	has_error
	)

Check if background operation has error.

Checks the BG.ERR_EXEC bit in the LPH status.

Parameters

handle	EnDAT3 handle
has_error	Pointer to store result (1 if background error is present, 0 otherwise)

Returns: ENDAT3_SUCCESS (0) on success ENDAT3_ERR_INVALID_INPUT (-1) if handle or has_error is NULL

◆ endat3_is_bg_busy()

int32_t endat3_is_bg_busy	(	endat3_handle	handle,
		uint8_t *	is_busy
	)

Check if background processor is busy.

Checks the BG.BUSY bit in the LPH status.

Parameters

handle	EnDAT3 handle
is_busy	Pointer to store result (1 if background processor is busy, 0 otherwise)

Returns: ENDAT3_SUCCESS (0) on success ENDAT3_ERR_INVALID_INPUT (-1) if handle or is_busy is NULL

◆ endat3_has_bg_rtx_error()

int32_t endat3_has_bg_rtx_error	(	endat3_handle	handle,
		uint8_t *	has_error
	)

Check if background RTX error occurred.

Checks the BG.RTX_ERROR bit in the LPH status.

Parameters

handle	EnDAT3 handle
has_error	Pointer to store result (1 if background RTX error occurred, 0 otherwise)

Returns: ENDAT3_SUCCESS (0) on success ENDAT3_ERR_INVALID_INPUT (-1) if handle or has_error is NULL

◆ endat3_get_lpf_status()

int32_t endat3_get_lpf_status	(	endat3_handle	handle,
		uint8_t	index,
		uint8_t *	status
	)

Get LPF status byte for specific frame.

Retrieves the status byte from a specific Low Priority Frame.

Parameters

handle	EnDAT3 handle
index	LPF frame index (0 to MAX_LPF_COUNT-1)
status	Pointer to store LPF status byte

Returns: ENDAT3_SUCCESS (0) on success ENDAT3_ERR_INVALID_INPUT (-1) if handle, status is NULL or index is invalid

◆ endat3_get_lpf_data()

int32_t endat3_get_lpf_data	(	endat3_handle	handle,
		uint8_t	index,
		uint8_t *	data
	)

Get LPF data array for specific frame.

Retrieves the 6-byte data payload from a specific Low Priority Frame.

Parameters

handle	EnDAT3 handle
index	LPF frame index (0 to MAX_LPF_COUNT-1)
data	Buffer to store LPF data (must be at least 6 bytes)

Returns: Number of bytes copied (6) on success; ENDAT3_ERR_INVALID_INPUT (-1) if handle is NULL, data is NULL, or index >= MAX_LPF_COUNT(8)

Note

Validation performed:

Handle and data buffer validation
Index bounds checking (index < MAX_LPF_COUNT)

uint8_t lpf_data[6];
int32_t bytes = endat3_get_lpf_data(handle, 0, lpf_data);
if(bytes == 6)
{
    // Process first LPF data
}

◆ endat3_get_lpf_crc()

int32_t endat3_get_lpf_crc	(	endat3_handle	handle,
		uint8_t	index,
		uint8_t *	crc
	)

Get LPF CRC value for specific frame.

Retrieves the CRC checksum from a specific Low Priority Frame for validation.

Parameters

handle	EnDAT3 handle
index	LPF frame index (0 to MAX_LPF_COUNT-1)
crc	Pointer to store LPF CRC byte

Returns: ENDAT3_SUCCESS (0) on success ENDAT3_ERR_INVALID_INPUT (-1) if handle, crc is NULL or index is invalid

◆ endat3_get_lpf_fid()

int32_t endat3_get_lpf_fid	(	endat3_handle	handle,
		uint8_t	index,
		uint8_t *	fid
	)

Get LPF FID (Frame ID) for specific frame.

Extracts the Frame ID from the LPF status byte.

Parameters

handle	EnDAT3 handle
index	LPF frame index (0 to MAX_LPF_COUNT-1)
fid	Pointer to store FID value (0-255)

Returns: ENDAT3_SUCCESS (0) on success ENDAT3_ERR_INVALID_INPUT (-1) if handle, fid is NULL or index is invalid

◆ endat3_is_connected()

int32_t endat3_is_connected	(	endat3_handle	handle,
		uint8_t *	is_connected
	)

Get connection status.

Checks if the encoder is connected and communicating.

Parameters

handle	EnDAT3 handle
is_connected	Pointer to store connection status (1 if connected, 0 otherwise)

Returns: ENDAT3_SUCCESS (0) on success ENDAT3_ERR_INVALID_INPUT (-1) if handle or is_connected is NULL

◆ endat3_is_busy()

int32_t endat3_is_busy	(	endat3_handle	handle,
		uint8_t *	is_busy
	)

Get busy status.

Checks if a transfer is currently in progress. Returns 1 only when encoder state is ENCODER_BUSY. Both ENCODER_IDLE and ENCODER_ERROR states return 0.

Parameters

handle	EnDAT3 handle
is_busy	Pointer to store busy status (1 if state == ENCODER_BUSY, 0 otherwise)

Returns: ENDAT3_SUCCESS (0) on success ENDAT3_ERR_INVALID_INPUT (-1) if handle or is_busy is NULL

◆ endat3_set_busy()

int32_t endat3_set_busy	(	endat3_handle	handle,
		uint8_t	busy
	)

Set or clear busy status.

Sets or clears the busy flag. Set busy=1 to mark a transfer as in progress; set busy=0 to clear the busy state when no transfer is active.

Parameters

handle	EnDAT3 handle
busy	Busy state to set (1 for busy, 0 for not busy)

Returns: ENDAT3_SUCCESS (0) on success; ENDAT3_ERR_INVALID_INPUT (-1) if handle is NULL, busy > 1, or internal structures are NULL

Note: Check return value to ensure state was set properly

◆ endat3_get_expected_tx_frame_count()

int32_t endat3_get_expected_tx_frame_count	(	endat3_handle	handle,
		uint32_t *	count
	)

Get expected TX frame count.

Retrieves the number of frames expected to be transmitted.

Parameters

handle	EnDAT3 handle
count	Pointer to store expected TX frame count

Returns: ENDAT3_SUCCESS (0) on success, ENDAT3_ERR_INVALID_INPUT (-1) if handle or count is NULL

◆ endat3_set_expected_tx_frame_count()

int32_t endat3_set_expected_tx_frame_count	(	endat3_handle	handle,
		uint32_t	count
	)

Set expected TX frame count.

Sets the number of frames expected to be transmitted.

Parameters

handle	EnDAT3 handle
count	Expected frame count

Returns: ENDAT3_SUCCESS (0) on success ENDAT3_ERR_INVALID_INPUT (-1) if handle is NULL

Note: Check return value - incorrect frame count causes communication errors

◆ endat3_get_propagation_time()

int32_t endat3_get_propagation_time	(	endat3_handle	handle,
		uint32_t *	prop_time
	)

Get propagation time.

Retrieves the measured propagation time from ECHO command. The value is in PRU clock cycles.

Parameters

handle	EnDAT3 handle
prop_time	Pointer to store propagation time in PRU clock cycles

Returns: ENDAT3_SUCCESS (0) on success, ENDAT3_ERR_INVALID_INPUT (-1) if handle or prop_time is NULL

uint32_t prop_time_cycles;
if(endat3_get_propagation_time(handle, &prop_time_cycles) == ENDAT3_SUCCESS)
{
    // Convert to nanoseconds (assuming 200MHz PRU clock)
    uint32_t prop_time_ns = (prop_time_cycles * 1000) / 200;
}

◆ endat3_get_foreground_op_code()

int32_t endat3_get_foreground_op_code	(	endat3_handle	handle,
		uint32_t *	opcode
	)

Get foreground operation code.

Retrieves the current foreground operation code.

Parameters

handle	EnDAT3 handle
opcode	Pointer to store foreground operation code

Returns: ENDAT3_SUCCESS (0) on success, ENDAT3_ERR_INVALID_INPUT (-1) if handle or opcode is NULL

◆ endat3_set_foreground_op_code()

int32_t endat3_set_foreground_op_code	(	endat3_handle	handle,
		uint32_t	opcode
	)

Set foreground operation code.

Sets the foreground operation code for the next command.

Parameters

handle	EnDAT3 handle
opcode	Operation code to set (use endat3_req_code enum values)

Returns: ENDAT3_SUCCESS (0) on success ENDAT3_ERR_INVALID_INPUT (-1) if handle is NULL CRITICAL: Check return value before calling endat3_send_command() - wrong opcode sends wrong command

if(endat3_set_foreground_op_code(handle, ENDAT3_REQ_DATA0) != ENDAT3_SUCCESS)
{
    DebugP_log("ERROR: Failed to set foreground opcode\r\n");
    return;
}

◆ endat3_get_background_op_code()

int32_t endat3_get_background_op_code	(	endat3_handle	handle,
		uint32_t *	opcode
	)

Get background operation code.

Retrieves the current background operation code.

Parameters

handle	EnDAT3 handle
opcode	Pointer to store background operation code

Returns: ENDAT3_SUCCESS (0) on success, ENDAT3_ERR_INVALID_INPUT (-1) if handle or opcode is NULL

◆ endat3_set_background_op_code()

int32_t endat3_set_background_op_code	(	endat3_handle	handle,
		uint32_t	opcode
	)

Set background operation code.

Sets the background operation code for the next command.

Parameters

handle	EnDAT3 handle
opcode	Operation code to set (use endat3_bg_req_opcode enum values)

Returns: ENDAT3_SUCCESS (0) on success ENDAT3_ERR_INVALID_INPUT (-1) if handle is NULL CRITICAL: Check return value before calling endat3_send_command() - wrong opcode sends wrong background operation

if(endat3_set_background_op_code(handle, ENDAT3_BGREQ_READ) != ENDAT3_SUCCESS)
{
    DebugP_log("ERROR: Failed to set background opcode\r\n");
    return;
}

◆ endat3_get_bg_data()

int32_t endat3_get_bg_data	(	endat3_handle	handle,
		uint8_t	index,
		uint32_t *	data
	)

Get background data word.

Retrieves a specific word from the background data array.

Parameters

handle	EnDAT3 handle
index	Data word index (0 to BG_DATA_SIZE-1)
data	Pointer to store the retrieved data value

Returns: ENDAT3_SUCCESS (0) on success, ENDAT3_ERR_INVALID_INPUT (-1) if handle, data is NULL, or index is invalid

◆ endat3_set_bg_data()

int32_t endat3_set_bg_data	(	endat3_handle	handle,
		uint8_t	index,
		uint32_t	data
	)

Set background data word.

Sets a specific word in the background data array.

Parameters

handle	EnDAT3 handle
index	Data word index (0 to BG_DATA_SIZE-1)
data	Data value to set

Returns: ENDAT3_SUCCESS (0) on success ENDAT3_ERR_INVALID_INPUT (-1) if handle is NULL or index >= BG_DATA_SIZE(6)

Note: Check return value - wrong background data sends incorrect command parameters

// Set RESET command data
if(endat3_set_bg_data(handle, 0, ENDAT3_RESET_HARD) != ENDAT3_SUCCESS)
{
    DebugP_log("ERROR: Failed to set background data\r\n");
    return;
}

◆ endat3_get_all_bg_data()

int32_t endat3_get_all_bg_data	(	endat3_handle	handle,
		uint32_t *	data
	)

Get all background data.

Retrieves all background data words into the provided buffer.

Parameters

handle	EnDAT3 handle
data	Buffer to store background data (must be at least BG_DATA_SIZE words = 6 words = 24 bytes)

Returns: ENDAT3_SUCCESS (0) on success ENDAT3_ERR_INVALID_INPUT (-1) if handle is NULL or data buffer is NULL

Note: Check return value to ensure data was retrieved successfully

◆ endat3_set_all_bg_data()

int32_t endat3_set_all_bg_data	(	endat3_handle	handle,
		const uint32_t *	data
	)

Set all background data.

Sets all background data words from the provided buffer. Copies exactly BG_DATA_SIZE (6) words (24 bytes) from the source buffer to the internal background data array.

Parameters

handle	EnDAT3 handle
data	Buffer containing background data (must be at least BG_DATA_SIZE words = 6 words = 24 bytes)

Returns: ENDAT3_SUCCESS (0) on success; ENDAT3_ERR_INVALID_INPUT (-1) if handle is NULL, data buffer is NULL, or internal structures are NULL

Note: This function copies a fixed size of BG_DATA_SIZE (6) words regardless of actual data content; Check return value to ensure data was set successfully

◆ endat3_get_rx_buffer()

const volatile uint8_t* endat3_get_rx_buffer ( endat3_handle handle )

Get RX buffer pointer.

Provides read-only access to the receive buffer.

Parameters

handle EnDAT3 handle

Returns: Pointer to RX buffer (RX_BUFFER_SIZE = 64 bytes), or NULL if handle is NULL

Warning: Do not modify the returned buffer. Use for read-only access.

◆ endat3_get_tx_buffer()

const volatile uint8_t* endat3_get_tx_buffer ( endat3_handle handle )

Get TX buffer pointer.

Provides read-only access to the transmit buffer.

Parameters

handle EnDAT3 handle

Returns: Pointer to TX buffer (TX_BUFFER_SIZE = 24 bytes), or NULL if handle is NULL

Warning: Do not modify the returned buffer. Use for read-only access.

◆ endat3_set_tx_buffer()

int32_t endat3_set_tx_buffer	(	endat3_handle	handle,
		const uint8_t *	data,
		uint32_t	length
	)

Copy data to TX buffer.

Safely copies data to the transmit buffer with bounds checking.

Parameters

handle	EnDAT3 handle
data	Source data buffer
length	Number of bytes to copy (1-24)

Returns: Number of bytes copied on success (1-24); ENDAT3_ERR_INVALID_INPUT (-1) if handle is NULL, data is NULL, length is 0, or length > TX_BUFFER_SIZE

◆ endat3_get_hpf_frame()

int32_t endat3_get_hpf_frame	(	endat3_handle	handle,
		endat3_hpf *	hpf
	)

Get complete HPF structure.

Retrieves the entire High Priority Frame structure.

Parameters

handle	EnDAT3 handle
hpf	Pointer to HPF structure to fill

Returns: ENDAT3_SUCCESS (0) on success; ENDAT3_ERR_INVALID_INPUT (-1) if handle or hpf is NULL

endat3_hpf hpf;
if(endat3_get_hpf_frame(handle, &hpf) == 0)
{
    // Access hpf.status, hpf.data, hpf.crc
}

◆ endat3_get_lph_frame()

int32_t endat3_get_lph_frame	(	endat3_handle	handle,
		endat3_lph *	lph
	)

Get complete LPH structure.

Retrieves the entire Low Priority Header structure.

Parameters

handle	EnDAT3 handle
lph	Pointer to LPH structure to fill

Returns: ENDAT3_SUCCESS (0) on success; ENDAT3_ERR_INVALID_INPUT (-1) if handle or lph is NULL

◆ endat3_get_lpf_frame()

int32_t endat3_get_lpf_frame	(	endat3_handle	handle,
		uint8_t	index,
		endat3_lpf *	lpf
	)

Get complete LPF structure.

Retrieves the entire Low Priority Frame structure for a specific index.

Parameters

handle	EnDAT3 handle
index	LPF frame index (0 to MAX_LPF_COUNT-1)
lpf	Pointer to LPF structure to fill

Returns: ENDAT3_SUCCESS (0) on success; ENDAT3_ERR_INVALID_INPUT (-1) if handle/lpf is NULL or index is invalid

◆ endat3_get_error_code()

int32_t endat3_get_error_code	(	endat3_handle	handle,
		endat3_error_code *	error_code
	)

Extract error code from HPF or LPF.

Extracts the error code from HPF data (when HPFV=0) or LPF data (when BG.ERR_EXEC is set).

Parameters

handle	EnDAT3 handle
error_code	Pointer to store error code value

Returns: ENDAT3_SUCCESS (0) on success ENDAT3_ERR_INVALID_INPUT (-1) if handle or error_code is NULL

endat3_error_code error;
if(endat3_get_error_code(handle, &error) == ENDAT3_SUCCESS)
{
    if(error != ENDAT3_ERR_UNKNOWN)
    {
        const char* desc = endat3_get_error_description(error);
        DebugP_log("Error: %s\r\n", desc);
    }
}

◆ endat3_get_interface()

endat3_interface* endat3_get_interface ( endat3_handle handle )

Get interface pointer (advanced use)

Provides direct access to the endat3_interface structure for advanced users who need full control. Use with caution.

Parameters

handle EnDAT3 handle

Returns: Pointer to endat3_interface structure, or NULL if handle is NULL

Warning: Direct manipulation of the interface structure can lead to undefined behavior. Use the provided APIs whenever possible.

◆ endat3_set_operating_mode()

int32_t endat3_set_operating_mode	(	endat3_handle	handle,
		uint8_t	opmode
	)

Set operating mode (host trigger or periodic trigger)

Configures the firmware operating mode for the EnDAT3 interface. This determines whether the encoder is triggered by host command, or sampled automatically when IEP counter reaches the configured CMP event compare value, or sampled automatically when an external signal triggers the IEP capture event.

**Configuration requirements for ENDAT3_OPMODE_PERIODIC_CMP :**

IEP hardware CMP registers must be configured separately
Use endat3_config_iep_cmp_event to set event number in firmware. This function is called inside endat3_init by default.
CMP event range: 0-15

**Configuration requirements for ENDAT3_OPMODE_PERIODIC_CAP :**

IEP hardware CAP registers must be configured separately
External signal to IEP capture input should be configured
Use endat3_config_iep_cap_event to set event number in firmware. This function is called inside endat3_init by default.
CAP event range: 0-7

Parameters

handle	EnDAT3 handle
opmode	Operating mode: 0 = periodic CMP trigger, 1 = host trigger, 2 = periodic CAP trigger

Returns: ENDAT3_SUCCESS (0) on success ENDAT3_ERR_INVALID_INPUT (-1) if handle is NULL ENDAT3_ERR_INVALID_OPMODE (-8) if opmode > 2 CRITICAL: Check return value - wrong operating mode causes complete communication failure

// Set to host trigger mode
if(endat3_set_operating_mode(handle, ENDAT3_OPMODE_HOST_TRIGGER) != ENDAT3_SUCCESS)
{
    DebugP_log("ERROR: Failed to set operating mode\r\n");
    return;
}
 
// Set to periodic trigger CMP mode
if(endat3_set_operating_mode(handle, ENDAT3_OPMODE_PERIODIC_CMP) != ENDAT3_SUCCESS)
{
    DebugP_log("ERROR: Failed to set operating mode\r\n");
    return;
}

◆ endat3_get_operating_mode()

int32_t endat3_get_operating_mode	(	endat3_handle	handle,
		uint8_t *	opmode
	)

Get current operating mode.

Retrieves the current firmware operating mode.

Parameters

handle	EnDAT3 handle
opmode	Pointer to store operating mode (0 = periodic CMP, 1 = host trigger, 2 = periodic CAP)

Returns: ENDAT3_SUCCESS (0) on success ENDAT3_ERR_INVALID_INPUT (-1) if handle or opmode is NULL

◆ endat3_config_iep_cap_event()

int32_t endat3_config_iep_cap_event	(	endat3_handle	handle,
		uint8_t	event_num
	)

Configure IEP CAP event number in PRU DMEM.

Parameters

handle	EnDAT3 handle
event_num	CAP event number (0-7) to use for periodic triggering

Returns: ENDAT3_SUCCESS (0) on success ENDAT3_ERR_INVALID_INPUT (-1) if handle is NULL or event_num > 7

Note: This only updates the DMEM configuration. The operating mode must be set to ENDAT3_OPMODE_PERIODIC_CAP separately via endat3_set_operating_mode(). This function does NOT configure IEP hardware registers.

◆ endat3_config_iep_cmp_event()

int32_t endat3_config_iep_cmp_event	(	endat3_handle	handle,
		uint8_t	event_num
	)

Configure IEP CMP event number in PRU DMEM.

Parameters

handle	EnDAT3 handle
event_num	CMP event number (0-15) to use for periodic triggering

Returns: ENDAT3_SUCCESS (0) on success ENDAT3_ERR_INVALID_INPUT (-1) if handle is NULL or event_num > 15

Note: This only updates the DMEM configuration. The operating mode must be set to ENDAT3_OPMODE_PERIODIC_CMP separately via endat3_set_operating_mode(). This function does NOT configure IEP hardware registers.

◆ endat3_release_start_trigger()

int32_t endat3_release_start_trigger ( endat3_handle handle )

Release start trigger to firmware.

Signals the firmware to begin processing by setting the start_trigger flag. The firmware will process the command based on the current operating mode:

In host mode: processes the command immediately
In periodic mode: waits for the next IEP CMP/CAP event

Parameters

handle EnDAT3 handle

Returns: ENDAT3_SUCCESS (0) on success ENDAT3_ERR_INVALID_INPUT (-1) if handle is NULL CRITICAL: Check return value - if this fails, command will never be processed by firmware

// Release trigger to firmware
if(endat3_release_start_trigger(handle) != ENDAT3_SUCCESS)
{
    DebugP_log("ERROR: Failed to release start trigger\r\n");
    return;
}

◆ endat3_clear_start_trigger()

int32_t endat3_clear_start_trigger ( endat3_handle handle )

Clear start trigger flag.

Clears the start_trigger flag after the firmware has processed the command. This prepares the interface for the next command.

Parameters

handle EnDAT3 handle

Returns: ENDAT3_SUCCESS (0) on success ENDAT3_ERR_INVALID_INPUT (-1) if handle is NULL

Note: Check return value to ensure trigger was cleared properly

◆ endat3_get_start_trigger_status()

int32_t endat3_get_start_trigger_status	(	endat3_handle	handle,
		uint8_t *	trigger_status
	)

Get current start trigger status.

Retrieves the current state of the start_trigger flag.

Parameters

handle	EnDAT3 handle
trigger_status	Pointer to store trigger status (1 if set, 0 if cleared)

Returns: ENDAT3_SUCCESS (0) on success ENDAT3_ERR_INVALID_INPUT (-1) if handle or trigger_status is NULL

Introduction

Parameter Validation Strategy

Typical Usage Flow

Data Structures

Functions

Typedefs

Enumerations

Macros

EnDat3 PRU Operating Modes

Macro Definition Documentation

◆ ENDAT3_MODE_SINGLE_CHANNEL_SINGLE_PRU

◆ ENDAT3_OPMODE_PERIODIC_CMP

◆ ENDAT3_OPMODE_HOST_TRIGGER

◆ ENDAT3_OPMODE_PERIODIC_CAP

◆ ENDAT3_SUCCESS

◆ ENDAT3_ERR_INVALID_INPUT

◆ ENDAT3_ERR_BUSY

◆ ENDAT3_ERR_RX_FAIL

◆ ENDAT3_ERR_LPH_CRC_FAIL

◆ ENDAT3_ERR_HPF_CRC_FAIL

◆ ENDAT3_ERR_LPF_CRC_FAIL

◆ ENDAT3_ERR_SAMPLING_ERROR

◆ ENDAT3_ERR_INVALID_OPMODE

◆ ENCODER_IDLE

◆ ENCODER_BUSY

◆ ENCODER_ERROR

◆ ENDAT3_FRAME_SIZE_BYTES

◆ ENDAT3_CHANNEL_MASK_MAX

◆ ENDAT3_MAX_BG_CMD_INDEX

◆ ENDAT3_CORE_CLK_200MHZ

◆ ENDAT3_CORE_CLK_300MHZ

◆ REFERENCE_PRU_FREQ_HZ

◆ REFERENCE_PRU_FREQ_HZ_FOR_SAMPLING

◆ ENDAT3_TX_START_DELAY_1_REF_CYCLES

◆ ENDAT3_TX_START_DELAY_2_REF_CYCLES

◆ ENDAT3_TX_START_DELAY_3_REF_CYCLES

◆ ENDAT3_DELAY_10MS_REF_CYCLES

◆ ENDAT3_BAUD_RATE_12_5_MBPS

◆ ENDAT3_BAUD_RATE_25_MBPS

◆ ENDAT3_BAUD_RATE_12_5_MBPS_VALUE

◆ ENDAT3_BAUD_RATE_25_MBPS_VALUE

◆ ENDAT3_IEP_MAX_CAP_EVENT

◆ ENDAT3_IEP_MAX_CMP_EVENT

◆ ENDAT3_CFG_REG_SIZE

◆ ENDAT3_CSL_ICSS_PR1_IEP0_SLV_CAP0_REG0

◆ ENDAT3_8_BYTE_REG_OFFSET

◆ ENDAT3_OVERSAMPLE_RATE_8X

◆ ENDAT3_SB_POLARITY

◆ ENDAT3_TX_CLOCK_MULTIPLIER

◆ HPF_DATA_SIZE

◆ LPF_DATA_SIZE

◆ MAX_LPF_COUNT

◆ LUT_SIZE

◆ RX_BUFFER_SIZE

◆ TX_BUFFER_SIZE

◆ BG_DATA_SIZE

◆ ENDAT3_HPF_TOTAL_SIZE

◆ ENDAT3_LPH_TOTAL_SIZE

◆ ENDAT3_LPF_TOTAL_SIZE

◆ ENDAT3_HPF_OFFSET

◆ ENDAT3_LPH_OFFSET

◆ ENDAT3_LPF_OFFSET

◆ ENDAT3_MIN_RX_BUFFER_SIZE

◆ ENDAT3_RESET_HARD

◆ ENDAT3_RESET_SOFT

◆ ENDAT3_CLEAR_F

◆ ENDAT3_CLEAR_W

◆ ENDAT3_CLEAR_REF

◆ ENDAT3_RATE_12_5MBPS

◆ ENDAT3_RATE_25MBPS

◆ ENDAT3_BUSINIT_RESET_ADDR

◆ ENDAT3_BUSINIT_KEEP_ADDR

◆ ENDAT3_PROTECT_QUERY

◆ ENDAT3_PROTECT_SET_READ

◆ ENDAT3_PROTECT_SET_WRITE

◆ ENDAT3_PASSWORD_HIGH_MASK

◆ ENDAT3_PASSWORD_LOW_MASK

◆ ENDAT3_PASSWORD_HIGH_SHIFT

◆ ENDAT3_PRE_LENGTH

◆ ENDAT3_POST_LENGTH