msLoggerCreate (Function)

This function will establish a logger that can be used to log motion sensor data into a user provided buffer.

The detailed configuration of the established logger is done with the functions msLoggerAddAcc, msLoggerAddGyr and msLoggerAddMag.

One can only have a maximum of 8 loggers at a time.

Data from a logger will always deliver a full set as the first set, and then depending on downsample values will deliver partial sets.

With downsampling on the accelerometer at 1, gyroscope 2 and magnetomter 3, the data received will look like:

When switching loggers, the first set will be a full set again.

In case there is no sensor sets for a given time, the timestamp will not be included, thus there can not be two successive timestamps.

Input:

Logger : SYSHANDLE

A user provided handle to uniquely identify the logger. See SYSHANDLE page. This field is mandatory.

Buffer : PTR

A pointer to the user provided buffer.

Size : DINT

Size in bytes of the user provided buffer. The size of the buffer must be at least 400 bytes for a cyclical buffer and otherwise at least 4000 bytes.

StopOnFull : BOOL (default FALSE)

If true, the buffer will stop collecting data when there is no more space for further data records in the buffer. Otherwise the buffer will function as a ring buffer.

Returns: INT

Declaration

FUNCTION msLoggerCreate : INT;
VAR_INPUT
  Logger       : ACCESS SYSHANDLE;
  Buffer       : MANDATORY PTR;
  Size         : MANDATORY DINT;
  StopOnFull   : BOOL := FALSE;
END_VAR;
 

Example:

// For a more complete example, see example under msReadEvent
INCLUDE rtcu.inc
 
PROGRAM test;
VAR
  logger       : SYSHANDLE;
  buf         : ARRAY[1..10000] OF DINT;
  rc           : INT;
END_VAR;
rc := msOpen();
DebugFmt(message:="msOpen (rc=\1)", v1:=rc);
...
rc := msLoggerCreate(logger:=logger, buffer:=ADDR(buf), size:=SIZEOF(buf), stoponfull:=TRUE);
DebugFmt(message:="msLoggerCreate (rc=\1) buffer_size=\4, stoponfull=TRUE", v1:=rc, v4:=SIZEOF(buf));
...
BEGIN
  ...
END;
END_PROGRAM;