Macros | |
#define | eyelink_tracker_time() eyelink_tracker_msec() |
#define | eyelink_time_offset() eyelink_msec_offset() |
Functions | |
UINT32 | eyelink_request_time (void) |
UINT32 | eyelink_node_request_time (ELINKADDR node) |
UINT32 | eyelink_read_time (void) |
double | eyelink_tracker_double_usec (void) |
UINT32 | eyelink_tracker_msec (void) |
double | eyelink_double_usec_offset (void) |
UINT32 | eyelink_msec_offset (void) |
These function produce a local estimate of the eye tracker clock. There are several time bases in the system: the eye tracker time, the local eyelink DLL time, and the OS system time. All of these may not run at the same speed, differing by up to 200 ppm (2 milliseconds every 10 seconds).
These functions give a reasonable estimate of the EyeLink tracker time that is used in EDF files and for sample and event timestamps over the link. The time estimate is perturbed by link delays, but will never decrease, but may jump forwards sometimes or "freeze" for a few milliseconds. Two resolution of time are given: milliseconds as returned by current_time(), and microseconds as returned by current_double_usec().
#define eyelink_time_offset | ( | ) | eyelink_msec_offset() |
#define eyelink_tracker_time | ( | ) | eyelink_tracker_msec() |
double eyelink_double_usec_offset | ( | void | ) |
Returns the time difference between the tracker time and display pc time.
current_time()
and eyelink_tracker_msec()
UINT32 eyelink_msec_offset | ( | void | ) |
Returns the time difference between the tracker time and display pc time.
UINT32 eyelink_node_request_time | ( | ELINKADDR | node | ) |
Sends a request the connected eye tracker to return its current time.
eyelink_read_time()
. node | Address of a specific tracker. |
0
if no error, else link error code.Example: See eyelink_request_time()
eyelink_request_time()
and eyelink_read_time()
UINT32 eyelink_read_time | ( | void | ) |
Returns the tracker time requested by eyelink_request_time()
or eyelink_node_request_time()
.
0
if no response yet, else timestamp in millisecond.Example: See eyelink_request_time()
eyelink_node_request_time()
and eyelink_request_time()
UINT32 eyelink_request_time | ( | void | ) |
Sends a request the connected eye tracker to return its current time.
eyelink_read_time()
. 0
if no error, else link error code.Example:
eyelink_node_request_time()
and eyelink_read_time()
double eyelink_tracker_double_usec | ( | void | ) |
Returns the current tracker time (in micro seconds) since the tracker application started.
Example:
UINT32 eyelink_tracker_msec | ( | void | ) |
Returns the current tracker time (in milliseconds) since the tracker application started.
Example: