Data Logging/Plotting

Inertial Sense provides data a logging capability in the EvalTool, CLTool, and SDK (C++) that can record data in binary, comma separated (.CSV), and KML file formats. This logging capability is useful for storing, replaying, and analyzing data.

Data Log Types

Comma Seperated Values (*.csv)

The comma separated value (.csv) file format can be imported into many software packages, including Excel, Matlab, and Python.

KML (*.kml)

KML is a file format used to display geographic data in an Earth browser such as Google Earth.

Binary Data Log (*.raw and *.dat)

	Raw Logger (*.raw)	Serial Logger (*.dat)
Description	Data stored in the same byte for byte form as it appears over a serial port, without parsing and removing packet header/footer.	Stores data to file in the same serial order it was passed into the logger. This is the default logger used in the CLTool and EvalTool.
Advantages	Allows logging of all data/packet formats. Preserves all data in the original form as communicated over serial port. Can be logged by writting serial port data to file, no parsing needed.	Optimized for real-time data logging.
Source File	DeviceLogRaw.h / .cpp	DeviceLogSerial.h / .cpp
File extension	.raw	.dat

Binary Data Log Format

This section outlines the Inertial Sense binary data log types known as raw data and serial data (.raw and .dat file extensions). The .dat data log file type are composed of several data containers know as chunks. Each chunk contains a header, sub-header, and data.

File

The data log file name has the format LOG_SNXXXXX_YYYYMMDD_HHMMSS_CNT.dat which contains the device serial number, date, time, and log file count. The serial data log file formats is .dat. This log consist of files containing series of data Chunks.

Standard data types are stored in the log files and are defined as:

U32	unsigned int
U16	unsigned short
S8	char
U8	unsigned char

Chunk

The data log file is composed of Chunks. A Chunk is a data container that provides an efficient method for organizing, handling, and parsing data in a file. A Chunk starts with a header which has a unique identifiable marker and ends with the data to be stored.

Chunk Header

The header, found at the start of each Chunk, is as follows:

The C structure implementation of the Chunk header is:

//!< Chunk Header
#pragma pack(push,1)
struct sChunkHeader
{
uint32_t marker; //!< Chunk marker (0xFC05EA32)
uint16_t version; //!< Chunk Version
uint16_t classification; //!< Chunk classification
char name[4]; //!< Chunk name
char invName[4]; //!< Bitwise inverse of chunk name
uint32_t dataSize; //!< Chunk data length in bytes
uint32_t invDataSize; //!< Bitwise inverse of chunk data length
uint32_t grpNum; //!< Chunk Group Number: 0 = serial data...
uint32_t devSerialNum; //!< Device serial number
uint32_t pHandle; //!< Device port handle
uint32_t reserved; //!< Unused
};
#pragma pack(pop)

Chunk Data

The Chunk data is defined for the .dat file types.

Data Set Header

The Data set header is used for the .dat file types.