sbgECom Binary Messages

The SBG_ECOM_CLASS_LOG_ECOM_0 (0x01) message class encompasses all binary messages that can be output by the device.
In addition to outputting data, some messages can also be used to input aiding information, such as the SBG_ECOM_LOG_AIR_DATA (36).

The sbgECom binary logs are designed for high data rates with minimal payload size.
This protocol is ideal for both real-time stabilization/navigation and post-processing applications.

Each message encapsulates a coherent set of data and status information that can be fully interpreted without requiring additional context. Users can configure the output rate for each message based on their specific requirements, optimizing the management of transmission bandwidth.

Message Timestamping

Each log includes a monotonic timestamp in microseconds, representing the time since the sensor was powered up.
This timestamp can be converted to GPS Time of Week (ToW) or UTC time using the SBG_ECOM_LOG_UTC_TIME message.

When valid GPS time is available from a GNSS receiver, the SBG_ECOM_LOG_UTC_TIME message provides both the timestamp and the corresponding GPS/UTC time.
This allows for straightforward conversion of any message timestamp to GPS/UTC time.

The following code sample demonstrates how to convert a message timestamp (msgTimeStampUs) to absolute GPS Time of Week in milliseconds.
The variable lastUtcMsg holds the latest valid SBG_ECOM_LOG_UTC_TIME information received.

const uint32_t  gpsTimeOfWeekMaxMs  = 60ul*60ul*24ul*7ul*1000ul;
 
int32_t         deltaTimeUs         = newMsg.timeStamp - lastUtcMsg.timeStamp;
int32_t         newMsgTowMs         = lastUtcMsg.gpsTimeOfWeek + deltaTimeUs/1000;
 
if (newMsgTowMs < 0)
{
  newMsgTowMs += gpsTimeOfWeekMaxMs;
}
else if (newMsgTowMs >= gpsTimeOfWeekMaxMs)
{
  newMsgTowMs -= gpsTimeOfWeekMaxMs;
}

Note

Timestamp to UTC time conversion is implemented in the sbgBasicLogger CLI tool.
For reference, you can review the CLoggerContext C++ implementation.

Messages Overview

The following list, provides a quick overview of all available logs for this message class.
It briefly describe which parameters are contained in each output log.

Name (Msg ID)	Description
SBG_ECOM_LOG_STATUS (01)	Status general, clock, com aiding, solution, heave
SBG_ECOM_LOG_UTC_TIME (02)	Provides UTC time reference
SBG_ECOM_LOG_IMU_DATA (03)	DEPRECATED: Synchronous body IMU rates and accelerations
SBG_ECOM_LOG_IMU_SHORT (44)	Body IMU rates and accelerations. Synchronous or asynchronous depending of the INS.
SBG_ECOM_LOG_EKF_EULER (06)	Includes roll, pitch, yaw and their accuracies on each axis
SBG_ECOM_LOG_EKF_QUAT (07)	Includes the 4 quaternions values
SBG_ECOM_LOG_EKF_NAV (08)	Position and velocities in NED coordinates with the accuracies on each axis
SBG_ECOM_LOG_EKF_VEL_BODY (54)	INS velocity expressed in body/vehicle frame.
SBG_ECOM_LOG_EKF_ROT_ACCEL_BODY (52)	Corrected Earth rate and gravity free rates and accelerations in body/vehicle frame.
SBG_ECOM_LOG_EKF_ROT_ACCEL_NED (53)	Corrected Earth rate and gravity free rates and accelerations in NED navigation frame.
SBG_ECOM_LOG_SHIP_MOTION (09)	Real time heave, surge, sway, accelerations and velocity
SBG_ECOM_LOG_SHIP_MOTION_HP (32)	Delayed heave, surge, sway, accelerations and velocity
SBG_ECOM_LOG_MAG (04)	Magnetic data with associated accelerometer on each axis
SBG_ECOM_LOG_MAG_CALIB (05)	Magnetometer calibration data (raw buffer)
SBG_ECOM_LOG_GPS1_VEL (13)	GNSS velocity from primary receiver
SBG_ECOM_LOG_GPS1_POS (14)	GNSS position from primary receiver
SBG_ECOM_LOG_GPS1_HDT (15)	GNSS true heading from primary receiver
SBG_ECOM_LOG_GPS1_RAW (31)	GNSS raw data from primary receiver
SBG_ECOM_LOG_GPS1_SAT (50)	GNSS satellite in view information from primary receiver
SBG_ECOM_LOG_GPS2_VEL (16)	GNSS velocity from secondary receiver
SBG_ECOM_LOG_GPS2_POS (17)	GNSS position from secondary receiver
SBG_ECOM_LOG_GPS2_HDT (18)	GNSS true heading from secondary receiver
SBG_ECOM_LOG_GPS2_RAW (38)	GNSS raw data from secondary receiver
SBG_ECOM_LOG_GPS2_SAT (51)	GNSS satellite in view information from secondary receiver
SBG_ECOM_LOG_ODO_VEL (19)	Provides odometer velocity measured by the device
SBG_ECOM_LOG_AIR_DATA (36)	Barometric altimeter input/output for airdata support
SBG_ECOM_LOG_DEPTH (47)	Depth sensor measurement log used for subsea navigation
SBG_ECOM_LOG_DVL_BOTTOM_TRACK (29)	Doppler Velocity Log for bottom tracking data
SBG_ECOM_LOG_DVL_WATER_TRACK (30)	Doppler Velocity log for water layer data
SBG_ECOM_LOG_USBL (37)	Raw USBL position data for subsea navigation
SBG_ECOM_LOG_EVENT_A (24)	Event marker sent when a signal is detected on Sync In A pin
SBG_ECOM_LOG_EVENT_B (25)	Event marker sent when a signal is detected on Sync In B pin
SBG_ECOM_LOG_EVENT_C (26)	Event marker sent when a signal is detected on Sync In C pin
SBG_ECOM_LOG_EVENT_D (27)	Event marker sent when a signal is detected on Sync In D pin
SBG_ECOM_LOG_EVENT_E (28)	Event marker sent when a signal is detected on Sync In E pin
SBG_ECOM_LOG_EVENT_OUT_A (45)	Event marker used to timestamp each generated Sync Out A signal
SBG_ECOM_LOG_EVENT_OUT_B (46)	Event marker used to timestamp each generated Sync Out B signal
SBG_ECOM_LOG_DIAG (48)	Returns error, warning, info and debug messages
SBG_ECOM_LOG_RTCM_RAW (49)	RTCM/NTRIP RAW data stream that can be used in post-processing
SBG_ECOM_LOG_SESSION_INFO (55)	Session information, including device information and current settings.
SBG_ECOM_LOG_PTP_STATUS (57)	Precise Time Protocol (PTP) status and metric values.

Messages Availability

In each message definition, you'll find details about the availability of the message for specific products and the firmware version in which it was introduced.
Some messages are specific to certain product capabilities, such as INS-only features or marine options.

For devices running up-to-date firmware, the new sbgInsRestApi can be used to easily query the list of supported output logs.
This can be done using a GET request to the following endpoint:

sbgEComApi -s COM1 -r 115200 -g /api/v1/messages/std

Messages Versions

SBG Systems continuously improves its products by adding new features and outputs.
This includes introducing new sbgECom binary messages and updating existing ones with additional fields and data.

Payload versions

Each message payload definition specifies whether new fields have been added in various sbgECom releases.
It is essential to determine the sbgECom version implemented by your device, as described here.

For example, the SBG_ECOM_LOG_STATUS output log has been updated with two new fields over time, as shown below:

Field	Description	Unit	Format	Size	Offset
TIME_STAMP	Time since sensor is powered up	µs	uint32	4	0
GENERAL_STATUS	General device status (see STATUS_GENERAL_STATUS)	-	uint16	2	4
COM_STATUS_2	Additional communication status (see STATUS_COM_STATUS_2)	-	uint16	2	6
COM_STATUS	Communication status (see STATUS_COM_STATUS)	-	uint32	4	8
AIDING_STATUS	Aiding equipment status (see STATUS_AIDING_STATUS)	-	uint32	4	12
RESERVED_2	Reserved status field for future use	-	uint32	4	16
RESERVED_3	Reserved field for future use	-	uint16	2	20
UP_TIME	System up time since the power on - 0 if N/A (added v1.7)	s	uint32	4	22
CPU_USAGE	Main CPU usage in percent - 0xFF if N/A (added v5.0)	%	uint8	1	23

Each new field addition corresponds to a specific sbgECom version, allowing developers to understand the evolution of the message and implement backward compatibility when necessary.

Backward/Upward Compatibility

New fields may be added to the end of a message payload over time, but fields are never removed to maintain backward binary compatibility.
If a field becomes obsolete, it will be marked as reserved or deprecated.

If you use an older sbgECom implementation to parse messages from a firmware with a newer sbgECom protocol, the parsing should still function correctly.
However, you will not have access to any new fields or features introduced in the latest firmware.

The sbgECom protocol implementation ensures compatibility by checking if a message payload meets the minimum required size.
Any additional fields beyond this size are parsed optionally, based on the remaining payload data.

For reference on this mechanism, you can review the SBG_ECOM_LOG_STATUS message parsing implementation in the sbgECom C library.

Warning

If you implement your own sbgECom protocol and message parsing, avoid checking for exact equality in the received message payload size.
Instead, follow the sbgECom message payload parsing C implementation to ensure upward compatibility.

Additional Messages

This sections covers output logs used to report device information, settings and for troubleshooting.

SBG_ECOM_LOG_DIAG (48)

This log is sent by the device whenever an internal error, warning, or informational message is generated.

• Message Name (ID): SBG_ECOM_LOG_DIAG (48)
• Compatibility: AHRS/INS capable products
• Firmware:
• Payload Size: Variable (6 bytes + message length)

Field	Description	Unit	Format	Size	Offset
TIME_STAMP	Time since the sensor was powered up	µs	uint32	4	0
TYPE	Type of message reported (see TYPE)	-	uint8	1	4
ERROR_CODE	Error code, if applicable (see SbgErrorCode)	-	uint8	1	5
MESSAGE	Detailed message as a NULL-terminated C string	-	char[]	[0-4080]	6

TYPE Definition

Value	Name	Description
0	SBG_DEBUG_LOG_TYPE_ERROR	Indicates an error; should not occur during normal operation
1	SBG_DEBUG_LOG_TYPE_WARNING	Indicates a warning; may occur during normal operation
2	SBG_DEBUG_LOG_TYPE_INFO	Provides informational content, useful for troubleshooting
3	SBG_DEBUG_LOG_TYPE_DEBUG	Debug information, available only with specific firmware

SBG_ECOM_LOG_RTCM_RAW (49)

This log stores the RTCM raw data stream received by the INS/GNSS module for RTK/DGPS positioning modes.
The RTCM data stream may originate from a serial/Ethernet interface or be retrieved via the built-in NTRIP client.

The data is stored as received, without modification, allowing Qinertia to use it for post-processing workflows and debugging.
Each message can contain up to 4086 bytes of data to fit within a standard sbgECom protocol frame.
The RTCM messages may be fragmented across multiple log entries depending on their length.

• Message Name (ID): SBG_ECOM_LOG_RTCM_RAW (49)
• Compatibility: INS capable products
• Firmware:
• Payload Size: Variable (up to 4086)

Field	Description	Unit	Format	Size	Offset
RAW_BUFFER	Bytes containing raw RTCM data received by the INS.	-	void	[0-4086]	0

SBG_ECOM_LOG_SESSION_INFO (55)

This log periodically streams device information and settings as a JSON string.

Since the JSON string can be large, it is split into smaller chunks to prevent delays in data transmission and avoid serial port saturation.
Each chunk is sent using the frame structure below, and the host is responsible for reassembling the chunks to reconstruct the full JSON message.

A new session info message is transmitted every minute, allowing the host to retrieve and log the latest device information and settings at any time.

• Message Name (ID): SBG_ECOM_LOG_SESSION_INFO (55)
• Compatibility: INS capable products
• Firmware:
• Payload Size: Variable (up to 70)

Field	Description	Unit	Format	Size	Offset
PAGE_INDEX	Zero-based index of the current chunk.	-	uint16	2	0
PAGE_COUNT	Total number of chunks in the current transmission.	-	uint16	2	2
DATA_SIZE	Size in bytes for the DATA field.	-	uint16	2	4
DATA	JSON data chunk, part of the full JSON message.	-	char[]	[0-64]	6

Status and Time

In this section you can find all sbgECom logs related to status reporting.

SBG_ECOM_LOG_STATUS (01)

This output combines all system status data, divided into several categories: General, Communications, Aiding.

This log is useful for advanced status information.

• Message Name (ID): SBG_ECOM_LOG_STATUS (01)
• Compatibility: All products
• Firmware:
• Payload Size: 27 bytes

Field	Description	Unit	Format	Size	Offset
TIME_STAMP	Time since sensor is powered up	µs	uint32	4	0
GENERAL_STATUS	General device status (see STATUS_GENERAL_STATUS)	-	uint16	2	4
COM_STATUS_2	Additional communication status (see STATUS_COM_STATUS_2)	-	uint16	2	6
COM_STATUS	Communication status (see STATUS_COM_STATUS)	-	uint32	4	8
AIDING_STATUS	Aiding equipment status (see STATUS_AIDING_STATUS)	-	uint32	4	12
RESERVED_2	Reserved status field for future use	-	uint32	4	16
RESERVED_3	Reserved field for future use	-	uint16	2	20
UP_TIME	System up time since the power on - 0 if N/A (added v1.7)	s	uint32	4	22
CPU_USAGE	Main CPU usage in percent - 0xFF if N/A (added v5.0)	%	uint8	1	23

Warning

The COM_STATUS_2 field has been introduced in sbgECom version 4.0. In previous versions, this field was reserved and not used.
Please ensure that you only utilize the additional communication status flags with products running firmware that supports sbgECom version 4.0 or later.

General device status (GENERAL_STATUS field)

Provides general device status and information such as the power supplies (main, IMU, GNSS), settings, temperature and data-logger.

Bit	Name	Type	Description
0	SBG_ECOM_GENERAL_MAIN_POWER_OK	Mask	Set if main power supply is OK.
1	SBG_ECOM_GENERAL_IMU_POWER_OK	Mask	Set if IMU power supply is OK.
2	SBG_ECOM_GENERAL_GPS_POWER_OK	Mask	Set if GPS power supply is OK.
3	SBG_ECOM_GENERAL_SETTINGS_OK	Mask	Set if settings are correctly loaded.
4	SBG_ECOM_GENERAL_TEMPERATURE_OK	Mask	Set if temperature is within specified limits.
5	SBG_ECOM_GENERAL_DATALOGGER_OK	Mask	Set if the data-logger is working correctly.
6	SBG_ECOM_GENERAL_CPU_OK	Mask	Set if the CPU headroom is correct.

Communication status (COM_STATUS field)

Provide information on ports, tells is they are valid or saturated.

Bit	Name	Type	Description
0	SBG_ECOM_PORTA_VALID	Mask	Set to 0 in case of low level communication error.
1	SBG_ECOM_PORTB_VALID	Mask	Set to 0 in case of low level communication error.
2	SBG_ECOM_PORTC_VALID	Mask	Set to 0 in case of low level communication error.
3	SBG_ECOM_PORTD_VALID	Mask	Set to 0 in case of low level communication error.
4	SBG_ECOM_PORTE_VALID	Mask	Set to 0 in case of low level communication error.
5	SBG_ECOM_PORTA_RX_OK	Mask	Set to 0 in case of saturation on PORT A input.
6	SBG_ECOM_PORTA_TX_OK	Mask	Set to 0 in case of saturation on PORT A output.
7	SBG_ECOM_PORTB_RX_OK	Mask	Set to 0 in case of saturation on PORT B input.
8	SBG_ECOM_PORTB_TX_OK	Mask	Set to 0 in case of saturation on PORT B output.
9	SBG_ECOM_PORTC_RX_OK	Mask	Set to 0 in case of saturation on PORT C input.
10	SBG_ECOM_PORTC_TX_OK	Mask	Set to 0 in case of saturation on PORT C output.
11	SBG_ECOM_PORTD_RX_OK	Mask	Set to 0 in case of saturation on PORT D input.
12	SBG_ECOM_PORTD_TX_OK	Mask	Set to 0 in case of saturation on PORT D output.
13	SBG_ECOM_PORTE_RX_OK	Mask	Set to 0 in case of saturation on PORT E input.
14	SBG_ECOM_PORTE_TX_OK	Mask	Set to 0 in case of saturation on PORT E output.
15	SBG_ECOM_ETH0_VALID	Mask	Set to 0 if the ETH 0 interface is either closed or in error.
16	SBG_ECOM_ETH1_VALID	Mask	Set to 0 if the ETH 1 interface is either closed or in error.
17	SBG_ECOM_ETH2_VALID	Mask	Set to 0 if the ETH 2 interface is either closed or in error.
18	SBG_ECOM_ETH3_VALID	Mask	Set to 0 if the ETH 3 interface is either closed or in error.
19	SBG_ECOM_ETH4_VALID	Mask	Set to 0 if the ETH 4 interface is either closed or in error.
25	SBG_ECOM_CAN_VALID	Mask	Set to 0 in case of low level communication error.
26	SBG_ECOM_CAN_RX_OK	Mask	Set to 0 in case of saturation on CAN Bus input buffer.
27	SBG_ECOM_CAN_TX_OK	Mask	Set to 0 in case of saturation on CAN Bus output buffer.
28-30	SBG_ECOM_CAN_BUS	Enum	CAN Bus status (see SBG_ECOM_CAN_BUS).

CAN Bus States

Reports CAN bus status:

Value	Name	Description
0	SBG_ECOM_CAN_BUS_OFF	Bus OFF operation due to too many errors.
1	SBG_ECOM_CAN_BUS_TX_RX_ERR	Transmit or receive error.
2	SBG_ECOM_CAN_BUS_OK	The CAN bus is working correctly.
3	SBG_ECOM_CAN_BUS_ERROR	A general error has occurred on the CAN bus.

Communication status (COM_STATUS_2 field)

Provide additional status on interfaces such as Ethernet.

Bit	Name	Type	Description
0	SBG_ECOM_COM2_ETH0_RX_OK	Mask	Set to 0 in case of error on ETH0 input such as saturation.
1	SBG_ECOM_COM2_ETH0_TX_OK	Mask	Set to 0 in case of error on ETH0 output such as saturation.
2	SBG_ECOM_COM2_ETH1_RX_OK	Mask	Set to 0 in case of error on ETH1 input such as saturation.
3	SBG_ECOM_COM2_ETH1_TX_OK	Mask	Set to 0 in case of error on ETH1 output such as saturation.
4	SBG_ECOM_COM2_ETH2_RX_OK	Mask	Set to 0 in case of error on ETH2 input such as saturation.
5	SBG_ECOM_COM2_ETH2_TX_OK	Mask	Set to 0 in case of error on ETH2 output such as saturation.
6	SBG_ECOM_COM2_ETH3_RX_OK	Mask	Set to 0 in case of error on ETH3 input such as saturation.
7	SBG_ECOM_COM2_ETH3_TX_OK	Mask	Set to 0 in case of error on ETH3 output such as saturation.
8	SBG_ECOM_COM2_ETH4_RX_OK	Mask	Set to 0 in case of error on ETH4 input such as saturation.
9	SBG_ECOM_COM2_ETH4_TX_OK	Mask	Set to 0 in case of error on ETH4 output such as saturation.

INS aiding status (AIDING_STATUS field)

Tells which aiding data is received.

Bit	Name	Type	Description
0	SBG_ECOM_AIDING_GPS1_POS_RECV	Mask	Set to 1 when valid GPS 1 position data is received
1	SBG_ECOM_AIDING_GPS1_VEL_RECV	Mask	Set to 1 when valid GPS 1 velocity data is received
2	SBG_ECOM_AIDING_GPS1_HDT_RECV	Mask	Set to 1 when valid GPS 1 true heading data is received
3	SBG_ECOM_AIDING_GPS1_UTC_RECV	Mask	Set to 1 when valid GPS 1 UTC time data is received
4	SBG_ECOM_AIDING_GPS2_POS_RECV	Mask	Set to 1 when valid GPS 2 position data is received
5	SBG_ECOM_AIDING_GPS2_VEL_RECV	Mask	Set to 1 when valid GPS 2 velocity data is received
6	SBG_ECOM_AIDING_GPS2_HDT_RECV	Mask	Set to 1 when valid GPS 2 true heading data is received
7	SBG_ECOM_AIDING_GPS2_UTC_RECV	Mask	Set to 1 when valid GPS 2 UTC time data is received
8	SBG_ECOM_AIDING_MAG_RECV	Mask	Set to 1 when valid Magnetometer data is received
9	SBG_ECOM_AIDING_ODO_RECV	Mask	Set to 1 when Odometer pulse is received
10	SBG_ECOM_AIDING_DVL_RECV	Mask	Set to 1 when valid DVL data is received
11	SBG_ECOM_AIDING_USBL_RECV	Mask	Set to 1 when valid USBL data is received
12	SBG_ECOM_AIDING_DEPTH_RECV	Mask	Set to 1 when valid Depth sensor data is received
13	SBG_ECOM_AIDING_AIR_DATA_RECV	Mask	Set to 1 when valid altitude and/or airspeed is received

SBG_ECOM_LOG_UTC_TIME (02)

Provides UTC time reference and internal clock estimation metrics.

This message provides a time correspondence between the device TIME_STAMP value and the actual UTC Time.
You should use this information to timestamp data to an absolute UTC or GPS time reference.

• Message Name (ID): SBG_ECOM_LOG_UTC_TIME (02)
• Compatibility: All products
• Firmware:
• Payload Size: 33 bytes

Field	Description	Unit	Format	Size	Offset
TIME_STAMP	Time since sensor is powered up	µs	uint32	4	0
TIME_STATUS	UTC time and clock sync status (see TIME_STATUS)	-	uint16	2	4
YEAR	Year	year	uint16	2	6
MONTH	Month in Year [1 ... 12]	month	uint8	1	8
DAY	Day in Month [1 … 31]	d	uint8	1	9
HOUR	Hour in day [0 … 23]	h	uint8	1	10
MIN	Minute in hour [0 … 59]	min	uint8	1	11
SEC	Second in minute [0 … 60]	s	uint8	1	12
NANOSEC	Nanosecond of second	ns	uint32	4	13
GPS_TOW	GPS Time of week	ms	uint32	4	17
CLK_BIAS_STD	Estimated clock bias 1-σ standard deviation – Added in v4.0	s	float	4	21
CLK_SF_ERROR_STD	Estimated scale factor 1-σ standard deviation – Added in v4.0	%	float	4	25
CLK_RESIDUAL_ERR	Measured error between GNSS PPS and internal clock – Added in v4.0	s	float	4	29

Note

The SEC field can report 60 seconds only when a leap second is inserted.

Warning

The UTC time status has changed in latest protocol versions (sbgECom 4.0 or later).
Once the UTC time is initialized and known it stays in this state.

Time and Clock status (TIME_STATUS field)

Provide information on the internal clock estimation and UTC status.

Bit	Name	Type	Description
0	HAS_CLOCK_INPUT	Mask	Set if a valid input clock signal (PPS) is detected.
[1-4]	CLOCK_STATE	Enum	Define the internal clock estimation status (see CLOCK_STATE)
5	UTC_IS_ACCURATE	Mask	Set if the reported UTC time is accurate (i.e., aligned with PPS).
[6-9]	UTC_STATUS	Enum	Define the UTC validity status (see UTC_STATUS)

Clock State (CLOCK_STATE field)

List internal clock alignment and correction state values:

Value	Name	Description
0	SBG_ECOM_CLOCK_STATE_ERROR	An error has occurred on the clock estimation.
1	SBG_ECOM_CLOCK_STATE_FREE_RUNNING	The clock is based on the internal crystal using latest estimated clock bias/sf.
2	SBG_ECOM_CLOCK_STATE_STEERING	A PPS has been detected and the clock is converging to it.
3	SBG_ECOM_CLOCK_STATE_VALID	The clock has converged to the PPS or is still considered to be accurate.

UTC Status (UTC_STATUS field)

List available UTC enum status:

Value	Name	Description
0	SBG_ECOM_UTC_STATUS_INVALID	The UTC time is not known and invalid. The firmware initial date time is used.
1	SBG_ECOM_UTC_STATUS_NO_LEAP_SEC	UTC time initialized but leap second is not known. Firmware leap second is used.
2	SBG_ECOM_UTC_STATUS_INITIALIZED	UTC time initialized with a fully resolved leap second information.

SBG_ECOM_LOG_PTP_STATUS (57)

Message that provides status and metrics regarding the embedded Precise Time Protocol (PTP) service.
It can report the time difference between the local INS time and an external GrandMaster clock.

The PTP service can operate in two different modes:

• Master: If the INS is the best available clock, it will broadcast PTP messages and act as a Grandmaster clock.
• Passive: Only listen for a PTP Grandmaster clock and reports the time delta between internal INS clock and PTP Grandmaster clock.

The message reporting the PTP status and accuracy is detailed below:

• Message Name (ID): SBG_ECOM_LOG_PTP_STATUS (57)
• Compatibility: High Performance INS
• Firmware:
• Payload Size: 82 bytes

Field	Description	Unit	Format	Size	Offset
TIME_STAMP	Time since sensor is powered up.	µs	uint32	4	0
STATUS	State, transport and time scale status (see PTP_STATUS).	-	uint16	2	4
TIME_SCALE_OFFSET	Internal time scale offset, in seconds.	s	double	8	6
LOCAL_CLOCK_IDENTITY	Local clock identity, UINT64_MAX if invalid.	-	uint64	4	14
LOCAL_CLOCK_PRIORITY1	Local clock priority1 attribute.	-	uint8	4	22
LOCAL_CLOCK_PRIORITY2	Local clock priority2 attribute.	-	uint8	4	23
LOCAL_CLOCK_CLASS	Local clock class attribute.	-	uint8	4	24
LOCAL_CLOCK_ACCURACY	Local clock accuracy.	-	uint8	4	25
LOCAL_CLOCK_LOG2_VARIANCE	Local clock variance expressed as an exponential (base 2).	-	uint16	4	26
LOCAL_CLOCK_TIME_SOURCE	Local clock time source.	-	uint8	4	28
MASTER_CLOCK_IDENTITY	Master clock identity, UINT64_MAX if invalid.	-	uint64	4	29
MASTER_CLOCK_PRIORITY1	Master clock priority1 attribute.	-	uint8	4	37
MASTER_CLOCK_PRIORITY2	Master clock priority2 attribute.	-	uint8	4	38
MASTER_CLOCK_CLASS	Master clock class attribute.	-	uint8	4	39
MASTER_CLOCK_ACCURACY	Master clock accuracy.	-	uint8	4	40
MASTER_CLOCK_LOG2_VARIANCE	Master clock variance expressed as an exponential (base 2).	-	uint16	4	41
MASTER_CLOCK_TIME_SOURCE	Master clock time source.	-	uint8	4	43
MASTER_IP_ADDRESS	Master clock IP address, UINT32_MAX if invalid.	-	uint32	4	44
MEAN_PATH_DELAY	Mean path delay to/from the master clock, NaN if not available.	s	float	4	48
MEAN_PATH_DELAY_STD_DEV	Mean path delay standard deviation, NaN if not available.	s	float	4	52
CLOCK_OFFSET	Offset between the local and master clocks, NaN if not available.	s	double	8	56
CLOCK_OFFSET_STD_DEV	Master clock offset standard deviation, NaN if not available.	s	float	4	64
CLOCK_FREQ_OFFSET	Offset between the frequency of the local and master clocks, NaN if not available.	Hz	float	4	68
CLOCK_FREQ_OFFSET_STD_DEV	Frequency offset standard deviation, NaN if not available.	Hz	float	4	72
MASTER_MAC_ADDRESS	Master clock MAC address, all fields to UINT32_MAX if invalid (added in v5.2).	-	uint8	6	76

Note

The local clock members are valid if and only if the local clock identity is valid. Similarly, the master clock members are valid if and only if the master clock identity is valid.

PTP_STATUS Definition

The PTP_STATUS field provides status details, including the main PTP mode, transport and internal time scale.
The field encodes several enumerations as described below:

Bits	Type	Name	Description
[0-2]	Enum	SBG_ECOM_LOG_PTP_STATE	Main PTP state. (see PTP_STATE).
[3-5]	Enum	SBG_ECOM_LOG_PTP_TRANSPORT	PTP transport (added in v5.2). (see PTP_TRANSPORT).
[6-7]		Reserved	Reserved for future use.
[8-10]	Enum	SBG_ECOM_LOG_PTP_TIME_SCALE	Internal time scale. (see PTP_TIME_SCALE).
[11-15]		Reserved	Reserved for future use.

PTP State

Main PTP operating mode and status.

Value	Name	Description
0	SBG_ECOM_LOG_PTP_STATE_DISABLED	PTP is disabled.
1	SBG_ECOM_LOG_PTP_STATE_FAULTY	The device is in the faulty state.
2	SBG_ECOM_LOG_PTP_STATE_MASTER	The device is the domain master.
3	SBG_ECOM_LOG_PTP_STATE_PASSIVE	The device is passive.

PTP Transport

The transport defines how PTP messages are sent between devices. The main options are:

• UDP (User Datagram Protocol): PTP messages are sent over IP networks (IPv4/IPv6), allowing synchronization across switches and routers.
  
• Ethernet: PTP messages are sent directly over Ethernet frames, providing lower latency and more precise synchronization in local networks.

Value	Name	Description
0	SBG_ECOM_LOG_PTP_TRANSPORT_UDP	Transport is UDP.
1	SBG_ECOM_LOG_PTP_TRANSPORT_ETHERNET	Transport is Ethernet (IEEE 802.3).

PTP Time Scale

This enumeration specifies the time scale used as the reference for broadcasting PTP time. The reference time can also include a positive or negative offset value specified by TIME_SCALE_OFFSET.

The IEEE 1588 standard specifies TAI (International Atomic Time) as the standard time scale for PTP (Precision Time Protocol).

Value	Name	Description
0	SBG_ECOM_LOG_PTP_TIME_SCALE_TAI	Reference time is TAI (International Atomic Time).
1	SBG_ECOM_LOG_PTP_TIME_SCALE_UTC	Reference time is UTC (Coordinated Universal Time).
2	SBG_ECOM_LOG_PTP_TIME_SCALE_GPS	Reference time is GPS (Global Positioning System Time).

IMU Measurements

This section details the messages used to report Inertial Measurement Unit (IMU) data as measured by the device's accelerometers and gyroscopes.
IMU measurements represent physical quantities, specifically accelerations in (m/s²) and angular rates in (rad/s) expressed in the device's body frame (X, Y, Z axes).

All IMU measurements are factory-calibrated to compensate for thermal drift, alignment errors, scale factors, and non-linearity.
The IMU data is ready for use in an Inertial Navigation System (INS) filter to compute the device's orientation and navigation solution.

Additionally, if any sensor frame alignment adjustments are made (such as rotating the device within a vehicle's frame), these will affect the reported IMU data.

Note

For vehicle rotation rates and accelerations compensated for gravity, earth rotation rate and residual errors, please check SBG_ECOM_LOG_EKF_ROT_ACCEL_BODY message.

IMU Data Synchronization Methods

Inertial Measurement Unit (IMU) data can be processed either synchronously or asynchronously, depending on the product series.
The synchronization method determines how IMU data is collected, processed, and output in relation to the main INS computation loop.

Synchronous IMU

For products like the ELLIPSE series and IMUs such as the PULSE-40, IMU data is synchronized with the main computation loop of the device.
Users can configure the output rate down to 1 Hz, with the device automatically downsampling the data using a moving average filter.

For instance, if the main sampling loop runs at 1 kHz and the output is set to 200 Hz, the device averages 5 samples to produce each output value.
Consequently, if 200 Hz is requested for both IMU and Extended Kalman Filter (EKF) data, exactly 200 messages per second for both IMU and EKF will be received.

Asynchronous IMU

High Performance INS products, such as the Navsight, Quanta, Ekinox, and Apogee series, operate with asynchronous IMU data.
In these systems, the IMU and INS do not share a common clock.
The IMU runs on its own clock, typically sampling at 200 Hz, while the INS operates its main processing loop also at 200 Hz but aligned with the GNSS time.

During each INS processing cycle, the latest IMU data messages are transmitted.
Depending on the timing discrepancies between the IMU and INS clocks, there may be 0, 1, or 2 IMU messages per INS processing cycle.

For example, if the system is set to output 200 Hz EKF data and IMU data triggered on a new data event, exactly 200 EKF messages per second will be received, while the number of IMU messages may slightly vary, influenced by the IMU clock's offset relative to the INS clock.

SBG_ECOM_LOG_IMU_DATA (03)

The message is deprecated and should not be used anymore.
It returns calibrated IMU data expressed in body frame as well as the IMU temperature.

• Message Name (ID): SBG_ECOM_LOG_IMU_DATA (03)
• Compatibility: All products
• Firmware:
• Payload Size: 58 bytes

Field	Description	Unit	Format	Size	Offset
TIME_STAMP	Time since sensor is powered up	µs	uint32	4	0
IMU_STATUS	IMU status (see IMU_DATA_STATUS)	-	uint16	2	4
ACCEL_0_X	Acceleration along the X axis in the body frame.	m/s²	float	4	6
ACCEL_0_Y	Acceleration along the Y axis in the body frame	m/s²	float	4	10
ACCEL_0_Z	Acceleration along the Z axis in the body frame	m/s²	float	4	14
GYRO_0_X	Rotation rate along the X axis in the body frame	rad/s	float	4	18
GYRO_0_Y	Rotation rate along the Y axis in the body frame	rad/s	float	4	22
GYRO_0_Z	Rotation rate along the Z axis in the body frame	rad/s	float	4	26
TEMPERATURE	IMU internal average temperature.	°C	float	4	30
ACCEL_1_X	Acceleration along the X axis in the body frame	m/s²	float	4	34
ACCEL_1_Y	Acceleration along the Y axis in the body frame	m/s²	float	4	38
ACCEL_1_Z	Acceleration along the Z axis in the body frame	m/s²	float	4	42
GYRO_1_X	Rotation rate along the X axis in the body frame	rad/s	float	4	46
GYRO_1_Y	Rotation rate along the Y axis in the body frame	rad/s	float	4	50
GYRO_1_Z	Rotation rate along the Z axis in the body frame	rad/s	float	4	54

Note

The fields ACCEL_0_* and ACCEL_1_* as well as GYRO_0_* and GYRO_1_* provide identical values. They are maintained for backward compatibility purposes.

Warning

Do not use this log for post-processing with software like Qinertia or for computing an INS solution.
Instead, refer to the new SBG_ECOM_LOG_IMU_SHORT message.

IMU Data Status

The IMU_DATA_STATUS field is a bitmask that indicates the health and status of the IMU.
Each bit represents a specific status flag, providing detailed information on various components of the IMU system.

Bit	Name	Description
0 (LSB)	SBG_ECOM_IMU_COM_OK	Set to 1 if communication with the IMU is working properly.
1	SBG_ECOM_IMU_STATUS_BIT	Set to 1 if the IMU passes internal BIT, including calibration and CPU checks.
2	SBG_ECOM_IMU_ACCEL_X_BIT	Set to 1 if the X-axis accelerometer passes PBIT and CBIT.
3	SBG_ECOM_IMU_ACCEL_Y_BIT	Set to 1 if the Y-axis accelerometer passes PBIT and CBIT.
4	SBG_ECOM_IMU_ACCEL_Z_BIT	Set to 1 if the Z-axis accelerometer passes PBIT and CBIT.
5	SBG_ECOM_IMU_GYRO_X_BIT	Set to 1 if the X-axis gyroscope passes PBIT and CBIT.
6	SBG_ECOM_IMU_GYRO_Y_BIT	Set to 1 if the Y-axis gyroscope passes PBIT and CBIT.
7	SBG_ECOM_IMU_GYRO_Z_BIT	Set to 1 if the Z-axis gyroscope passes PBIT and CBIT.
8	SBG_ECOM_IMU_ACCELS_IN_RANGE	Set to 1 if all accelerometers are operating within the specified range.
9	SBG_ECOM_IMU_GYROS_IN_RANGE	Set to 1 if all gyroscopes are operating within the specified range.

Note

PBIT (Power-On Built-In Tests): These tests are conducted once when the IMU is powered on, ensuring that all essential systems are functioning correctly at startup.
CBIT (Continuous Built-In Tests): These tests are performed continuously during operation, monitoring the health and status of the IMU components in real-time.

SBG_ECOM_LOG_IMU_SHORT (44)

The SBG_ECOM_LOG_IMU_SHORT message reports IMU data, including accelerations and rotation rates expressed in the IMU body frame, in a compact and efficient format.

For High Performance INS, this log is asynchronous and can only be triggered on a New Data event.
For ELLIPSE v3 and IMUs like the PULSE-40, this log is synchronous ans can be output at any rate from 1 Hz up to the maximum rate supported by the device.
Typically 1 kHz for ELLIPSE v3 and up to 2 kHz for IMU-only products like the PULSE-40.

To ensure the best dynamic range and LSB accuracy, measurements are provided using int32 integers with a fixed scaling.
For high rotation rates above ~1833°/s, a different high range scaling is applied.

Note

This message supersedes the deprecated SBG_ECOM_LOG_IMU_DATA message.

• Message Name (ID): SBG_ECOM_LOG_IMU_SHORT (44)
• Compatibility: All products
• Firmware:
• Payload Size: 32 bytes

Field	Description	Unit	Format	Size	Offset
TIME_STAMP	Time since sensor is powered up	µs	uint32	4	0
IMU_STATUS	IMU status (see IMU_STATUS)	-	uint16	2	4
ACCELERATION_X	Acceleration along the X axis in the body frame (in LSB).	m/s²	int32	4	6
ACCELERATION_Y	Acceleration along the Y axis in the body frame (in LSB).	m/s²	int32	4	10
ACCELERATION_Z	Acceleration along the Z axis in the body frame (in LSB).	m/s²	int32	4	14
RATE_X	Rotation rate along the X axis in the body frame (in LSB).	rad/s	int32	4	18
RATE_Y	Rotation rate along the Y axis in the body frame (in LSB).	rad/s	int32	4	22
RATE_Z	Rotation rate along the Z axis in the body frame (in LSB).	rad/s	int32	4	26
TEMPERATURE	IMU internal average temperature (in LSB).	°C	int16	2	30

Converting to Physical Quantities

Temperature

The temperature is using a fixed scaling of 256 LSB for 1°C: temperature = temperatureLSB / 256

Accelerations

The accelerations are using a fixed scaling of 1048576 LSB for 1 m/s²: acceleration = accelerationLSB / 1048576

Rotation Rates

The rotation rates are using two different scaling:

• Standard Scaling: 67108864 LSB for 1 rad/s if SBG_ECOM_IMU_GYROS_USE_HIGH_SCALE flag is not set.
• High Range Scaling: 12304174 LSB for 1 rad/s if SBG_ECOM_IMU_GYROS_USE_HIGH_SCALE flag is set.

The device automatically switches to high range scaling when any rotation rate component exceeds approximately 1833°/s.

The following code snippet illustrates how to convert rotation rates from LSB to rad/s:

if (status & SBG_ECOM_IMU_GYROS_USE_HIGH_SCALE)
{
  rate = rateLSB / 12304174.0;
}
else
{
  rate = rateLSB / 67108864.0;
}

Note

Most SBG Systems products, such as the ELLIPSE, have a rotation rate range below 1000°/s and thus only use the standard scaling.

IMU Status

The IMU_STATUS field is a bitmask that indicates the health and status of the IMU.
Each bit represents a specific status flag, providing detailed information on various components of the IMU system.

Bit	Name	Description
0 (LSB)	SBG_ECOM_IMU_COM_OK	Set if communication with the IMU is working properly.
1	SBG_ECOM_IMU_STATUS_BIT	Set if the IMU passes internal BIT, including calibration and CPU checks.
2	SBG_ECOM_IMU_ACCEL_X_BIT	Set if the X-axis accelerometer passes PBIT and CBIT.
3	SBG_ECOM_IMU_ACCEL_Y_BIT	Set if the Y-axis accelerometer passes PBIT and CBIT.
4	SBG_ECOM_IMU_ACCEL_Z_BIT	Set if the Z-axis accelerometer passes PBIT and CBIT.
5	SBG_ECOM_IMU_GYRO_X_BIT	Set if the X-axis gyroscope passes PBIT and CBIT.
6	SBG_ECOM_IMU_GYRO_Y_BIT	Set if the Y-axis gyroscope passes PBIT and CBIT.
7	SBG_ECOM_IMU_GYRO_Z_BIT	Set if the Z-axis gyroscope passes PBIT and CBIT.
8	SBG_ECOM_IMU_ACCELS_IN_RANGE	Set if all accelerometers are operating within the specified range.
9	SBG_ECOM_IMU_GYROS_IN_RANGE	Set if all gyroscopes are operating within the specified range.
10	SBG_ECOM_IMU_GYROS_USE_HIGH_SCALE	Set if the high scale scale factor is being used for rotation rates.

Note

PBIT (Power-On Built-In Tests): These tests are conducted once when the IMU is powered on, ensuring that all essential systems are functioning correctly at startup.
CBIT (Continuous Built-In Tests): These tests are performed continuously during operation, monitoring the health and status of the IMU components in real-time.

Attitude, Velocity, Position

The following logs present the output of the navigation unit, vehicle attitude (represented by Euler angles and quaternions), velocity, and position data.
These logs share common status flags and enumerations, which are detailed in the subsequent sections.

Additionally, this section includes logs that provide compensated vehicle accelerations and rotation rates.
Unlike raw IMU data, these measurements have been processed by the INS Extended Kalman Filter to correct for sensor biases and scale factors.

Furthermore, the effects of Earth's gravity and rotation rate are also removed, providing data that accurately reflects the vehicle's true dynamics.

SOLUTION_STATUS

This status provides information about the Extended Kalman Filter (EKF), indicating which aiding data is used and the current solution mode.

Bit	Name	Description
[0-3]	SBG_ECOM_SOLUTION_MODE	Indicates the Kalman filter computation mode (see SOLUTION_MODE)
4	SBG_ECOM_SOL_ATTITUDE_VALID	Set if attitude data is reliable (Roll/Pitch error within defined criteria).
5	SBG_ECOM_SOL_HEADING_VALID	Set if heading data is reliable (Heading error within defined criteria).
6	SBG_ECOM_SOL_VELOCITY_VALID	Set if velocity data is reliable (Velocity error within defined criteria).
7	SBG_ECOM_SOL_POSITION_VALID	Set if position data is reliable (Position error within defined criteria).
8	SBG_ECOM_SOL_VERT_REF_USED	Set if the vertical reference is used in the solution.
9	SBG_ECOM_SOL_MAG_REF_USED	Set if magnetometer is used in the solution.
10	SBG_ECOM_SOL_GPS1_VEL_USED	Set if GNSS 1 velocity is used in the solution.
11	SBG_ECOM_SOL_GPS1_POS_USED	Set if GNSS 1 position is used in the solution.
13	SBG_ECOM_SOL_GPS1_HDT_USED	Set if GNSS 1 true heading is used in the solution.
14	SBG_ECOM_SOL_GPS2_VEL_USED	Set if GNSS 2 velocity is used in the solution.
15	SBG_ECOM_SOL_GPS2_POS_USED	Set if GNSS 2 position is used in the solution.
17	SBG_ECOM_SOL_GPS2_HDT_USED	Set if GNSS 2 true heading is used in the solution.
18	SBG_ECOM_SOL_ODO_USED	Set if odometer velocity is used in the solution.
19	SBG_ECOM_SOL_DVL_BT_USED	Set if DVL bottom tracking velocity is used in the solution.
20	SBG_ECOM_SOL_DVL_WT_USED	Set if DVL water layer velocity is used in the solution.
24	SBG_ECOM_SOL_USBL_USED	Set if USBL position is used in the solution.
25	SBG_ECOM_SOL_AIR_DATA_USED	Set if altitude or true airspeed is used in the solution.
26	SBG_ECOM_SOL_ZUPT_USED	Set if a Zero Velocity Update (ZUPT) is is used in the solution.
27	SBG_ECOM_SOL_ALIGN_VALID	Set if sensor alignment and residual sensors errors have fully converged.
28	SBG_ECOM_SOL_DEPTH_USED	Set if depth sensor is used in the solution (subsea navigation).
29	SBG_ECOM_SOL_ZARU_USED	Set if a Zero Angular Rate Update (ZARU) is used in the solution.

SOLUTION_MODE

Value	Name	Description
0	SBG_ECOM_SOL_MODE_UNINITIALIZED	Kalman filter is not initialized; data is invalid.
1	SBG_ECOM_SOL_MODE_VERTICAL_GYRO	Computes roll and pitch; heading and position drift freely.
2	SBG_ECOM_SOL_MODE_AHRS	Full orientation with heading reference; navigation data may drift.
3	SBG_ECOM_SOL_MODE_NAV_VELOCITY	Deprecated. Not in use.
4	SBG_ECOM_SOL_MODE_NAV_POSITION	Full computation of attitude, velocity, and position.

Note

The Used in Solution flags have a 3s timeout mechanism for easier interpretation.
For instance, the SBG_ECOM_SOL_ODO_USED flag remains valid for 3 seconds after the odometer was last used in the solution.

SBG_ECOM_LOG_EKF_EULER (06)

This log provides the Euler angles (roll, pitch, yaw) and their associated accuracies, along with the AHRS/INS solution status.

• Message Name (ID): SBG_ECOM_LOG_EKF_EULER (06)
• Compatibility: AHRS/INS capable products
• Firmware:
• Payload Size: 40 bytes

Field	Description	Unit	Format	Size	Offset
TIME_STAMP	Time since the sensor was powered up	µs	uint32	4	0
ROLL	Roll angle	rad	float	4	4
PITCH	Pitch angle	rad	float	4	8
YAW	Yaw angle (geographic heading)	rad	float	4	12
ROLL_ACC	1σ standard deviation of roll angle accuracy	rad	float	4	16
PITCH_ACC	1σ standard deviation of pitch angle accuracy	rad	float	4	20
YAW_ACC	1σ standard deviation of yaw angle accuracy	rad	float	4	24
SOLUTION_STATUS	INS solution status (see SOLUTION_STATUS)	-	uint32	4	28
MAG_DECL	Local magnetic declination, positive East.	rad	float	4	32
MAG_INCL	Local magnetic inclination, positive Down.	rad	float	4	36

SBG_ECOM_LOG_EKF_QUAT (07)

This log provides the INS orientation using quaternions which avoid gimbal lock and are valid for all orientations.
It also includes the standard deviation accuracies for roll, pitch, and yaw angles, along with the AHRS/INS solution status.

• Message Name (ID): SBG_ECOM_LOG_EKF_QUAT (07)
• Compatibility: AHRS/INS capable products
• Firmware:
• Payload Size: 44 bytes

Field	Description	Unit	Format	Size	Offset
TIME_STAMP	Time since the sensor was powered up	µs	uint32	4	0
Q0	First quaternion parameter (W component)	-	float	4	4
Q1	Second quaternion parameter (X component)	-	float	4	8
Q2	Third quaternion parameter (Y component)	-	float	4	12
Q3	Fourth quaternion parameter (Z component)	-	float	4	16
ROLL_ACC	1σ standard deviation of roll angle accuracy	rad	float	4	20
PITCH_ACC	1σ standard deviation of pitch angle accuracy	rad	float	4	24
YAW_ACC	1σ standard deviation of yaw angle accuracy	rad	float	4	28
SOLUTION_STATUS	INS solution status (see SOLUTION_STATUS)	-	uint32	4	32
MAG_DECL	Local magnetic declination, positive East.	rad	float	4	36
MAG_INCL	Local magnetic inclination, positive Down.	rad	float	4	40

SBG_ECOM_LOG_EKF_NAV (08)

This log provides the INS velocity in the North-East-Down (NED) coordinate system and position in Latitude, Longitude, and Altitude.
It also includes accuracy parameters for each measurement along with the INS solution status.

• Message Name (ID): SBG_ECOM_LOG_EKF_NAV (08)
• Compatibility: INS capable products
• Firmware:
• Payload Size: 72 bytes

Field	Description	Unit	Format	Size	Offset
TIME_STAMP	Time since the sensor was powered up	µs	uint32	4	0
VELOCITY_N	Velocity in the North direction	m/s	float	4	4
VELOCITY_E	Velocity in the East direction	m/s	float	4	8
VELOCITY_D	Velocity in the Down direction	m/s	float	4	12
VELOCITY_N_ACC	1σ standard deviation of velocity accuracy in North direction	m/s	float	4	16
VELOCITY_E_ACC	1σ standard deviation of velocity accuracy in East direction	m/s	float	4	20
VELOCITY_D_ACC	1σ standard deviation of velocity accuracy in Down direction	m/s	float	4	24
LATITUDE	Geographic latitude, positive North.	°	double	8	28
LONGITUDE	Geographic longitude, positive East.	°	double	8	36
ALTITUDE	Altitude above Mean Sea Level (MSL), positive upward.	m	double	8	44
UNDULATION	Difference between geoid and ellipsoid altitude	m	float	4	52
LATITUDE_ACC	1σ standard deviation of latitude accuracy	m	float	4	56
LONGITUDE_ACC	1σ standard deviation of longitude accuracy	m	float	4	60
ALTITUDE_ACC	1σ standard deviation of vertical position accuracy	m	float	4	64
SOLUTION_STATUS	INS solution status (see SOLUTION_STATUS)	-	uint32	4	68

Note

The undulation can be used to compute the height above ellipsoid from the MSL altitude.
Please use the following formula: height = altitude + undulation

SBG_ECOM_LOG_EKF_VEL_BODY (54)

This log provides the INS velocity expressed in the body/vehicle frame.

When the INS is correctly configured, the body frame aligns with the vehicle frame.
For instance, in a car, the X-axis points forward, and the Y-axis points to the right.

• Message Name (ID): SBG_ECOM_LOG_EKF_VEL_BODY (54)
• Compatibility: INS capable products
• Firmware:
• Payload Size: 32 bytes

Field	Description	Unit	Format	Size	Offset
TIME_STAMP	Time since the sensor was powered up	µs	uint32	4	0
SOLUTION_STATUS	INS solution status (see SOLUTION_STATUS)	-	uint32	4	4
VELOCITY_X	Velocity along the X-axis (forward direction in vehicle frame)	m/s	float	4	8
VELOCITY_Y	Velocity along the Y-axis (right direction in vehicle frame)	m/s	float	4	12
VELOCITY_Z	Velocity along the Z-axis (downward direction in vehicle frame)	m/s	float	4	16
VELOCITY_X_ACC	1σ standard deviation of velocity accuracy along the X-axis	m/s	float	4	20
VELOCITY_Y_ACC	1σ standard deviation of velocity accuracy along the Y-axis	m/s	float	4	24
VELOCITY_Z_ACC	1σ standard deviation of velocity accuracy along the Z-axis	m/s	float	4	28

SBG_ECOM_LOG_EKF_ROT_ACCEL_BODY (52)

This log provides the corrected rotation rates and accelerations in the INS body/vehicle frame.
The data is compensated by the Navigation Filter for sensor bias, scale factor, earth rotation, and gravity.

• Message Name (ID): SBG_ECOM_LOG_EKF_ROT_ACCEL_BODY (52)
• Compatibility: INS capable products
• Firmware:
• Payload Size: 32 bytes

Field	Description	Unit	Format	Size	Offset
TIME_STAMP	Time since the sensor was powered up	µs	uint32	4	0
SOLUTION_STATUS	INS solution status (see SOLUTION_STATUS)	-	uint32	4	4
RATE_X	Rotation rate around the X axis	rad/s	float	4	8
RATE_Y	Rotation rate around the Y axis	rad/s	float	4	12
RATE_Z	Rotation rate around the Z axis	rad/s	float	4	16
ACCELERATION_X	Acceleration along the X axis	m/s²	float	4	20
ACCELERATION_Y	Acceleration along the Y axis	m/s²	float	4	24
ACCELERATION_Z	Acceleration along the Z axis	m/s²	float	4	28

Note

This log is properly decimated based on the selected output rate to prevent aliasing issues.

SBG_ECOM_LOG_EKF_ROT_ACCEL_NED (53)

This log provides the corrected rotation rates and accelerations in the North, East, Down (NED) navigation frame.
The data is compensated by the Navigation Filter for sensor bias, scale factor, earth rotation, and gravity.

This log is particularly useful for determining a vehicle's turn rate, such as the down rotation rate.

• Message Name (ID): SBG_ECOM_LOG_EKF_ROT_ACCEL_NED (53)
• Compatibility: INS capable products
• Firmware:
• Payload Size: 32 bytes

Field	Description	Unit	Format	Size	Offset
TIME_STAMP	Time since the sensor was powered up	µs	uint32	4	0
SOLUTION_STATUS	INS solution status (see SOLUTION_STATUS)	-	uint32	4	4
RATE_N	Rotation rate around the North axis in the navigation frame	rad/s	float	4	8
RATE_E	Rotation rate around the East axis in the navigation frame	rad/s	float	4	12
RATE_D	Rotation rate around the Down axis in the navigation frame	rad/s	float	4	16
ACCELERATION_N	Acceleration along the North axis in the navigation frame	m/s²	float	4	20
ACCELERATION_E	Acceleration along the East axis in the navigation frame	m/s²	float	4	24
ACCELERATION_D	Acceleration along the Down axis in the navigation frame	m/s²	float	4	28

Note

This log is properly decimated based on the selected output rate to prevent aliasing issues.

Warning

Rotation rates around the North and East navigation axes are not commonly used.
In most cases, rotation rates in the body X and Y axes are preferable.

Surge, Sway, Heave

This section covers output measurements specific to marine applications, including Surge, Sway, and Heave.

High-performance INS units with marine options support both real-time and delayed heave measurements.
The ELLIPSE Series, however, offers real-time heave measurements only, without surge or sway channels.

Real-time heave delivers immediate data, whereas delayed heave offers higher accuracy with a 150-second time delay.

Real-time and delayed ship motion outputs share common conventions, message structures, status flags, and enumerations, as detailed below.

Output frame and monitoring point

Ship motion measurements are defined in a vessel-specific coordinate frame:

• Heave: Vertical displacement, (positive downward)
• Surge: Longitudinal displacement (positive toward the bow/forward).
• Sway: Transverse displacement (positive toward the starboard side/right).

The heave measurements are affected by the selected output monitoring point and will be re-located accordingly.
However, surge/sway/velocity and accelerations values are only valid when output at the IMU monitoring point.

Ship Motion Status

The status field indicates the validity and availability of the ship motion output fields.
It is crucial to check this status to determine which fields are active and if the data is valid.

Bit	Name	Description
0	SBG_ECOM_HEAVE_VALID	Set if heave has stabilized (see SBG_ECOM_HEAVE_VALID)
1	SBG_ECOM_HEAVE_VEL_AIDED	Set if the heave output is compensated for transient accelerations
2	SBG_ECOM_HEAVE_SURGE_SWAY_INCLUDED	Set if surge and sway components are included in this output
3	SBG_ECOM_HEAVE_PERIOD_INCLUDED	Set if the swell period is provided
4	SBG_ECOM_HEAVE_PERIOD_VALID	Set if the swell period data is valid
5	SBG_ECOM_HEAVE_SWELL_MODE	Set if real-time heave uses swell mode computations

SBG_ECOM_HEAVE_VALID flag

The SBG_ECOM_HEAVE_VALID flag indicates whether the heave measurement is valid and stable, as it relies on high-pass filtering that requires convergence.
This flag is cleared under the following conditions:

• At startup or before convergence
• After a turn occurs without velocity aiding
• When heave measurements reach extreme values
• If a significant step occurs, necessitating filter re-convergence
• In the event of an internal system failure

SBG_ECOM_LOG_SHIP_MOTION (09)

This log provides real-time ship motion data, including main heave period, surge, sway, heave, velocity, and accelerations.

• Message Name (ID): SBG_ECOM_LOG_SHIP_MOTION (09)
• Compatibility: AHRS/INS with marine/hydro options
• Firmware:
• Payload Size: 46 bytes

Field	Description	Unit	Format	Size	Offset
TIME_STAMP	Time since the sensor was powered up	µs	uint32	4	0
HEAVE_PERIOD	Main heave period	s	float	4	4
SURGE	Surge longitudinal displacement (positive forward)	m	float	4	8
SWAY	Sway lateral displacement (positive right)	m	float	4	12
HEAVE	Heave vertical displacement (positive down)	m	float	4	16
ACCEL_X	Longitudinal acceleration (positive forward)	m/s²	float	4	20
ACCEL_Y	Lateral acceleration (positive right)	m/s²	float	4	24
ACCEL_Z	Vertical acceleration (positive down)	m/s²	float	4	28
VEL_X	Longitudinal velocity (positive forward)	m/s	float	4	32
VEL_Y	Lateral velocity (positive right)	m/s	float	4	36
VEL_Z	Vertical velocity (positive down)	m/s	float	4	40
STATUS	Ship motion output status (see SHIP_MOTION_STATUS)	-	uint32	4	28

Note

ELLIPSE series only computes and outputs HEAVE_PERIOD, HEAVE, ACCEL_Z and VEL_Z values.
All other fields are set to zero and reported as invalid in the STATUS bitmask.

Warning

Surge, sway, velocities and accelerations values are only valid when output at the IMU monitoring point.

SBG_ECOM_LOG_SHIP_MOTION_HP (32)

This log provides delayed heave measurements, offering higher accuracy compared to real-time at the cost of approximately 150 seconds of delayed output.

The timestamp reported in the message reflects the actual time of data validity.
The data corresponds to conditions roughly 150 seconds earlier than other logs transmitted at the same time.

• Message Name (ID): SBG_ECOM_LOG_SHIP_MOTION_HP (32)
• Compatibility: High Performance INS (marine option)
• Firmware:
• Payload Size: 46 bytes

Field	Description	Unit	Format	Size	Offset
TIME_STAMP	Time since the sensor was powered up	µs	uint32	4	0
HEAVE_PERIOD	Reserved for future use. Always reported as 0	s	float	4	4
SURGE	Reserved for future use. Always reported as 0	m	float	4	8
SWAY	Reserved for future use. Always reported as 0	m	float	4	12
HEAVE	Heave vertical displacement (positive down)	m	float	4	16
ACCEL_X	Reserved for future use. Always reported as 0	m/s²	float	4	20
ACCEL_Y	Reserved for future use. Always reported as 0	m/s²	float	4	24
ACCEL_Z	Vertical acceleration (positive down)	m/s²	float	4	28
VEL_X	Reserved for future use. Always reported as 0	m/s	float	4	32
VEL_Y	Reserved for future use. Always reported as 0	m/s	float	4	36
VEL_Z	Vertical velocity (positive down)	m/s	float	4	40
STATUS	Ship motion output status (see SHIP_MOTION_STATUS)	-	uint32	4	28

Note

The SBG_ECOM_LOG_SHIP_MOTION_HP message only computes and outputs delayed heave, vertical velocity and acceleration.
All other fields are reported as 0 and the STATUS bitmask is set accordingly.

Warning

Vertical velocity and acceleration are only valid when output at the IMU monitoring point.

GNSS aiding (PVT, HDT)

The following logs provide the navigation unit's output, including Euler angles, quaternions, velocity and position.
These logs share common status flags and enumerations, detailed below.

GNSS Velocity

This section details the velocity and course information from the primary or secondary GNSS receiver.
The timestamp reflects the actual time of the GNSS velocity data, independent of the main processing loop.

• Message Name (ID): SBG_ECOM_LOG_GPS1_VEL (13), SBG_ECOM_LOG_GPS2_VEL (16)
• Compatibility: INS capable products
• Firmware:
• Payload Size: 44 bytes

Field	Description	Unit	Format	Size	Offset
TIME_STAMP	Time since sensor was powered up	µs	uint32	4	0
STATUS_TYPE	Velocity solution type and status (see GPS_VEL_STATUS_TYPE)	-	uint32	4	4
TOW	GPS Time of Week	ms	uint32	4	8
VEL_N	Velocity in North direction	m/s	float	4	12
VEL_E	Velocity in East direction	m/s	float	4	16
VEL_D	Velocity in Down direction	m/s	float	4	20
VEL_ACC_N	1σ Accuracy in North direction	m/s	float	4	24
VEL_ACC_E	1σ Accuracy in East direction	m/s	float	4	28
VEL_ACC_D	1σ Accuracy in Down direction	m/s	float	4	32
COURSE	True direction of motion over ground	°	float	4	36
COURSE_ACC	1σ course accuracy	°	float	4	40

Status and Solution Type Field

The STATUS_TYPE field provides both the GNSS velocity solution status and the type of computed velocity, encoded as two separate enumerations.

Bits	Type	Name	Description
[0-5]	Enum	SBG_ECOM_GPS_VEL_STATUS	The GPS velocity status (see GPS_VEL_STATUS).
[6-11]	Enum	SBG_ECOM_GPS_VEL_TYPE	The GPS velocity type (see GPS_VEL_STATUS).

GNSS Velocity Status Enumeration

Indicates the general status of the GNSS regarding velocity computation.

Value	Name	Description
0	SBG_ECOM_VEL_SOL_COMPUTED	A valid solution has been computed.
1	SBG_ECOM_VEL_INSUFFICIENT_OBS	Not enough valid SVs to compute a solution.
2	SBG_ECOM_VEL_INTERNAL_ERROR	An internal error has occurred.
3	SBG_ECOM_VEL_LIMIT	Velocity limit exceeded.

GNSS Velocity Type Enumeration

Specifies the type of the computed velocity solution.

Value	Name	Description
0	SBG_ECOM_VEL_NO_SOLUTION	No valid velocity solution available.
1	SBG_ECOM_VEL_UNKNOWN_TYPE	An unknown solution type has been computed.
2	SBG_ECOM_VEL_DOPPLER	A Doppler velocity has been computed.
3	SBG_ECOM_VEL_DIFFERENTIAL	A velocity has been determined by calculating the difference between two sequential position measurements.

Note

Ensure that both the GNSS velocity solution status and type are checked to validate the output velocity data.

GNSS Position

This section provides position information from the primary or secondary GNSS receiver.
The timestamp indicates the actual GPS position data time, not synchronized with the main processing loop.

• Message Name (ID): SBG_ECOM_LOG_GPS1_POS (14), SBG_ECOM_LOG_GPS2_POS (17)
• Compatibility: INS capable products
• Firmware:
• Payload Size: 59 bytes

Field	Description	Unit	Format	Size	Offset
TIME_STAMP	Time since the sensor was powered up	µs	uint32	4	0
STATUS_TYPE	Position solution type and status (see GPS_POS_STATUS_TYPE)	-	uint32	4	4
TOW	GNSS Time of Week	ms	uint32	4	8
LATITUDE	Latitude, positive North	°	double	8	12
LONGITUDE	Longitude, positive East	°	double	8	20
ALTITUDE	Altitude Above Mean Sea Level	m	double	8	28
UNDULATION	Altitude difference between the geoid and the Ellipsoid	m	float	4	36
LAT_ACC	1σ Latitude Accuracy	m	float	4	40
LONG_ACC	1σ Longitude Accuracy	m	float	4	44
ALTI_ACC	1σ Altitude Accuracy	m	float	4	48
NUM_SV_USED	Number of space vehicles used in GNSS solution - 0xFF if N/A (since v1.4)	-	uint8	1	52
BASE_STATION_ID	ID of the DGPS/RTK base station in use - 0xFFFF if N/A (since v1.4)	-	uint16	2	53
DIFF_AGE	Differential data age - 0xFFFF if N/A (since v1.4)	0.01s	uint16	2	55
NUM_SV_TRACKED	Number of tracked SV - 0xFF if N/A (since v4.0)	-	uint8	1	57
STATUS_EXT	Interference/spoofing status (see GPS_POS_STATUS_EXT). (since v4.0)	-	uint32	4	58

Status and Solution Type Field

The STATUS_TYPE field provides both the GNSS position solution status and the type of computed position, encoded as two separate enumerations.
It also includes bitmasks to reports which signals are being used to compute the solution.

Bits	Type	Name	Description
[0-5]	Enum	SBG_ECOM_GPS_POS_STATUS	GNSS position status (see GPS_POS_STATUS)
[6-11]	Enum	SBG_ECOM_GPS_POS_TYPE	GNSS position type (see GPS_POS_TYPE)
12	Mask	SBG_ECOM_GPS_POS_GPS_L1_USED	Set if GPS L1CA/L1P is used in the solution
13	Mask	SBG_ECOM_GPS_POS_GPS_L2_USED	Set if GPS L2P/L2C is used in the solution
14	Mask	SBG_ECOM_GPS_POS_GPS_L5_USED	Set if GPS L5 is used in the solution
15	Mask	SBG_ECOM_GPS_POS_GLO_L1_USED	Set if GLONASS L1CA is used in the solution
16	Mask	SBG_ECOM_GPS_POS_GLO_L2_USED	Set if GLONASS L2C/L2P is used in the solution
17	Mask	SBG_ECOM_GPS_POS_GLO_L3_USED	Set if GLONASS L3 is used in the solution
18	Mask	SBG_ECOM_GPS_POS_GAL_E1_USED	Set if Galileo E1 is used in the solution
19	Mask	SBG_ECOM_GPS_POS_GAL_E5A_USED	Set if Galileo E5a is used in the solution
20	Mask	SBG_ECOM_GPS_POS_GAL_E5B_USED	Set if Galileo E5b is used in the solution
21	Mask	SBG_ECOM_GPS_POS_GAL_E5ALT_USED	Set if Galileo E5 AltBoc is used in the solution
22	Mask	SBG_ECOM_GPS_POS_GAL_E6_USED	Set if Galileo E6 is used in the solution
23	Mask	SBG_ECOM_GPS_POS_BDS_B1_USED	Set if BeiDou B1 is used in the solution
24	Mask	SBG_ECOM_GPS_POS_BDS_B2_USED	Set if BeiDou B2 is used in the solution
25	Mask	SBG_ECOM_GPS_POS_BDS_B3_USED	Set if BeiDou B3 is used in the solution
26	Mask	SBG_ECOM_GPS_POS_QZSS_L1_USED	Set if QZSS L1CA is used in the solution
27	Mask	SBG_ECOM_GPS_POS_QZSS_L2_USED	Set if QZSS L2C is used in the solution
28	Mask	SBG_ECOM_GPS_POS_QZSS_L5_USED	Set if QZSS L5 is used in the solution
29	Mask	SBG_ECOM_GPS_POS_QZSS_L6_USED	Set if QZSS L6 is used in the solution

GNSS Position Status Enumeration

Specifies the type of the computed velocity solution.

Value	Name	Description
0	SBG_ECOM_POS_SOL_COMPUTED	A valid solution has been computed
1	SBG_ECOM_POS_INSUFFICIENT_OBS	Not enough valid SV to compute a solution
2	SBG_ECOM_POS_INTERNAL_ERROR	An internal error has occurred
3	SBG_ECOM_POS_HEIGHT_LIMIT	The height limit has been exceeded

GNSS Position Type Enumeration

Specifies the type of the computed velocity solution.

Value	Name	Description
0	SBG_ECOM_POS_NO_SOLUTION	No valid solution available
1	SBG_ECOM_POS_UNKNOWN_TYPE	An unknown solution type has been computed
2	SBG_ECOM_POS_SINGLE	Single point solution position
3	SBG_ECOM_POS_PSRDIFF	Standard Pseudorange Differential Solution (DGPS)
4	SBG_ECOM_POS_SBAS	SBAS satellite used for differential corrections
5	SBG_ECOM_POS_OMNISTAR	Omnistar VBS Position (L1 sub-meter)
6	SBG_ECOM_POS_RTK_FLOAT	Floating RTK ambiguity solution (20 cm RTK)
7	SBG_ECOM_POS_RTK_INT	Integer RTK ambiguity solution (2 cm RTK)
8	SBG_ECOM_POS_PPP_FLOAT	Precise Point Positioning with float ambiguities
9	SBG_ECOM_POS_PPP_INT	Precise Point Positioning with fixed ambiguities
10	SBG_ECOM_POS_FIXED	Fixed location solution position

Note

Ensure that both the GNSS position solution status and type are checked to validate the output position data.

STATUS_EXT Definition

The STATUS_EXT field provides additional status details, including interference monitoring and spoofing detection. The field encodes several enumerations as described below:

Bits	Type	Name	Description
[0-3]	Enum	SBG_ECOM_GNSS_IFM_STATUS	GNSS interference monitoring and mitigation (see GNSS_IFM_STATUS).
[4-7]	Enum	SBG_ECOM_GNSS_SPOOFING_STATUS	GNSS spoofing monitoring and mitigation (see GNSS_SPOOFING_STATUS).
[8-11]	Enum	SBG_ECOM_GNSS_OSNMA_STATUS	Galileo OSNMA authentication status (see GNSS_OSNMA_STATUS).

Interference Monitoring Status Enumeration

Value	Name	Description
0	IFM_STATUS_ERROR	The interference monitoring system is in error and not operational
1	IFM_STATUS_UNKNOWN	Interference monitoring is disabled or not available
2	IFM_STATUS_CLEAN	Interference monitored and the environment is clean
3	IFM_STATUS_MITIGATED	Interference detected and mitigated, PVT is valid
4	IFM_STATUS_CRITICAL	Interference detected and not mitigated, PVT is invalid

Spoofing Status Enumeration

Value	Name	Description
0	SPOOFING_STATUS_ERROR	Spoofing detection system error, not operational
1	SPOOFING_STATUS_UNKNOWN	Spoofing detection disabled or not available
2	SPOOFING_STATUS_CLEAN	Spoofing detection enabled, no spoofing detected
3	SPOOFING_STATUS_SINGLE	Probable spoofing detected by one method
4	SPOOFING_STATUS_MULTIPLE	Confirmed spoofing detected by multiple methods (Galileo OSNMA, RAIM).

OSNMA Status Enumeration

Value	Name	Description
0	OSNMA_STATUS_ERROR	OSNMA is in error state and doesn't work.
1	OSNMA_STATUS_DISABLED	OSNMA is either disabled or not available.
2	OSNMA_STATUS_INITIALIZING	OSNMA initialization in progress.
3	OSNMA_STATUS_WAITING_NTP	Awaiting valid time from NTP server for strict mode operation.
4	OSNMA_STATUS_VALID	Actively authenticating Galileo signals, no spoofing.
5	OSNMA_STATUS_SPOOFED	Spoofing detected on Galileo signals.

GNSS True Heading

Provides true heading data from the primary or secondary dual antenna GNSS receiver.
The timestamp represents the actual time of the GPS true heading data.

• Message Name (ID): SBG_ECOM_LOG_GPS1_HDT (15), SBG_ECOM_LOG_GPS2_HDT (18)
• Compatibility: INS capable products
• Firmware:
• Payload Size: 32 bytes

Field	Description	Unit	Format	Size	Offset
TIME_STAMP	Time since the sensor was powered up	µs	uint32	4	0
STATUS	GNSS True Heading status (see GPS_HDT_STATUS_BIT)	-	uint16	2	4
TOW	GPS Time of Week	ms	uint32	4	6
TRUE_HEADING	True heading angle (0 to 360°)	°	float	4	10
TRUE_HEADING_ACC	1σ True heading estimated accuracy (0 to 360°)	°	float	4	14
PITCH	Pitch angle from the master to the rover (-90 to +90°)	°	float	4	18
PITCH_ACC	1σ pitch estimated accuracy (0 to 90°)	°	float	4	22
BASELINE	Distance between main and auxiliary antenna (since v1.11)	m	float	4	26
NUM_SV_TRACKED	Number of space vehicles tracked for true heading - 0xFF if N/A (since v4.0)	-	uint8	1	30
NUM_SV_USED	Number of SV used in true heading solution - 0xFF if N/A (since v4.0)	-	uint8	1	31

Status and Validity

The STATUS field indicates the status of the GNSS true heading solution along with additional validity information.

Bits	Type	Name	Description
[0-5]	Enum	SBG_ECOM_GPS_HDT_STATUS	GNSS true heading status (see GPS_HDT_STATUS)
6	Mask	SBG_ECOM_GPS_HDT_BASELINE_VALID	Set if the baseline length field is valid

GNSS True Heading Status Enumeration

Value	Name	Description
0	SBG_ECOM_HDT_SOL_COMPUTED	A valid solution has been computed
1	SBG_ECOM_HDT_INSUFFICIENT_OBS	Not enough valid SV to compute a solution
2	SBG_ECOM_HDT_INTERNAL_ERROR	An internal error has occurred
3	SBG_ECOM_HDT_HEIGHT_LIMIT	The height limit has been exceeded

GNSS Raw Data

This log is used to store raw GPS data for post-processing purposes.
It directly stores untouched binary messages from the GNSS receiver, relevant for post-processing.

Each message can contain up to 4086 bytes of raw GNSS data to fit within a standard sbgECom protocol frame.

• Message Name (ID): SBG_ECOM_LOG_GPS1_RAW (31), SBG_ECOM_LOG_GPS2_RAW (38)
• Compatibility: INS capable products
• Firmware:
• Payload Size: Variable (up to 4086)

Field	Description	Unit	Format	Size	Offset
RAW_BUFFER	Buffer storing GNSS raw data as returned by the receiver	-	void	[0-4086]	0

GNSS Space Vehicles Information

List of all space vehicles in view by the primary or secondary GNSS receiver antenna.
This message is typically sent every second with the latest information from the GNSS receiver.

It includes details on the constellation, identifier/PRN, elevation, azimuth, and health status of each satellite, along with tracked signals.

• Message Name (ID): SBG_ECOM_LOG_GPS1_SAT (50), SBG_ECOM_LOG_GPS2_SAT (51)
• Compatibility: INS capable products
• Firmware:
• Payload Size: Variable (up to 4086)

Field	Description	Unit	Format	Size	Offset
timeStamp	Time since sensor is powered up	µs	uint32	4	0
reserved	Reserved, do not use	-	uint32	4	4
nrSatellites	Number of reported satellites 0 to 64 (see SatData)	-	uint8	1	8

Repeated Group: SatData (nrSatellites times)

This block provides information for a satellite such as elevation, satellite id etc.
It is repeated nrSatellites times.

Field	Description	Unit	Format	Size	Offset
satelliteId	RINEX Satellite number (see GNSS_SAT_ID)	-	uint8	1	-
elevation	Satellite elevation (-90 to +90°)	°	int8	1	-
azimuth	Satellite azimuth (0 to 359°)	°	uint16	2	-
satFlags	Satellite status flags (see satFlags)	-	uint16	2	-
nrSignals	Number of reported signals 0 to 8 (see SignalData)	-	uint8	1	-

satFlags Definition

Bits	Type	Name	Description
[0-2]	Enum	Tracking status	Tracking Status (see SAT_TRACKING_STATUS).
[3-4]	Enum	Health status	Health Status (see SAT_HEALTH_STATUS).
[5-6]	Enum	Elevation status	Elevation Status (see SAT_ELEVATION_STATUS).
[7-10]	Enum	Constellation	Satellite constellation (see GNSS_CONSTELLATION).

Repeated Group: SignalData (nrSignals times)

This block provides information for a specific signal of a satellite.
It is repeated nrSignals for a satellite.

Field	Description	Unit	Format	Size	Offset
signalId	Signal unique identifier (see GNSS_SAT_ID)	-	uint8	1	-
sigFlags	Signal status flags (see sigFlags)	-	uint8	1	-
snr	Signal-to-Noise ratio	dB	uint8	1	-

sigFlags Definition

Bits	Type	Name	Description
[0-2]	Enum	Tracking status	Tracking Status (see SAT_TRACKING_STATUS).
[3-4]	Enum	Health status	Health Status (see SAT_HEALTH_STATUS).
5	Mask	SNR valid	Set if the Signal-to-Noise Ratio information is available.

Common Definitions

The definitions below are shared across SatData and SignalData blocks.

Tracking Status Enum

Value	Name	Description
0	SBG_ECOM_SAT_TRACKING_STATUS_UNKNOWN	Unknown tracking status (e.g., no signal or idle)
1	SBG_ECOM_SAT_TRACKING_STATUS_SEARCHING	Signal being searched, not yet usable
2	SBG_ECOM_SAT_TRACKING_STATUS_TRACKING_UNKNOWN	Signal tracked, use in solution unknown
3	SBG_ECOM_SAT_TRACKING_STATUS_TRACKING_NOT_USED	Signal tracked, not used in the solution
4	SBG_ECOM_SAT_TRACKING_STATUS_TRACKING_REJECTED	Signal tracked but rejected (e.g., due to jamming)
5	SBG_ECOM_SAT_TRACKING_STATUS_TRACKING_USED	Signal tracked and used in the GNSS solution

Health Status Enum

Value	Name	Description
0	SBG_ECOM_SAT_HEALTH_STATUS_UNKNOWN	Satellite or signal health is unknown
1	SBG_ECOM_SAT_HEALTH_STATUS_HEALTHY	The satellite or signal is healthy
2	SBG_ECOM_SAT_HEALTH_STATUS_UNHEALTHY	The satellite or signal is unhealthy

Elevation Status Enum

Value	Name	Description
0	SBG_ECOM_SAT_ELEVATION_STATUS_UNKNOWN	Elevation status unknown
1	SBG_ECOM_SAT_ELEVATION_STATUS_SETTING	The satellite elevation is setting
2	SBG_ECOM_SAT_ELEVATION_STATUS_RISING	The satellite elevation is rising

Aiding Equipments

The following logs provide the navigation unit's output, including Euler angles, quaternions, velocity and position.
These logs share common status flags and enumerations, detailed below.

SBG_ECOM_LOG_MAG (04)

This log provides calibrated magnetometer data along with associated accelerometer readings.
When an internal magnetometer is used, the accelerometer data is sourced from the internal IMU.

• Message Name (ID): SBG_ECOM_LOG_MAG (04)
• Compatibility: ELLIPSE AHRS/INS
• Firmware:
• Payload Size: 30 bytes

Field	Description	Unit	Format	Size	Offset
TIME_STAMP	Time since the sensor was powered up	µs	uint32	4	0
MAG_STATUS	Magnetometer status bitmask (see MAG_STATUS)	-	uint16	2	4
MAG_X	Magnetic field along the X axis in the body frame.	a.u	float	4	6
MAG_Y	Magnetic field along the Y axis in the body frame.	a.u	float	4	10
MAG_Z	Magnetic field along the Z axis in the body frame.	a.u	float	4	14
ACCEL_X	Acceleration along the X axis in the body frame.	m/s²	float	4	18
ACCEL_Y	Acceleration along the Y axis in the body frame.	m/s²	float	4	22
ACCEL_Z	Acceleration along the Z axis in the body frame.	m/s²	float	4	26

Note

Magnetic field measurements are expressed in Arbitrary Units (A.U.) as they are used to determine magnetic heading.
After successful magnetic calibration, the magnetic field values are normalized to one.

MAG_STATUS Definition

Bit	Name	Description
0	SBG_ECOM_MAG_MAG_X_BIT	Set if the magnetometer X-axis passes the self-test
1	SBG_ECOM_MAG_MAG_Y_BIT	Set if the magnetometer Y-axis passes the self-test
2	SBG_ECOM_MAG_MAG_Z_BIT	Set if the magnetometer Z-axis passes the self-test
3	SBG_ECOM_MAG_ACCEL_X_BIT	Set if the accelerometer X-axis passes the self-test
4	SBG_ECOM_MAG_ACCEL_Y_BIT	Set if the accelerometer Y-axis passes the self-test
5	SBG_ECOM_MAG_ACCEL_Z_BIT	Set if the accelerometer Z-axis passes the self-test
6	SBG_ECOM_MAG_MAGS_IN_RANGE	Set if the magnetometer is not saturated
7	SBG_ECOM_MAG_ACCELS_IN_RANGE	Set if the accelerometer is not saturated
8	SBG_ECOM_MAG_CALIBRATION_OK	Set if the magnetometer appears to be calibrated

SBG_ECOM_LOG_MAG_CALIB (05)

This log provides a raw buffer for magnetic calibration procedures, such as those performed using the sbgCenter software.

• Message Name (ID): SBG_ECOM_LOG_MAG_CALIB (05)
• Compatibility: ELLIPSE AHRS/INS
• Firmware:
• Payload Size: 22 bytes

Field	Description	Unit	Format	Size	Offset
TIME_STAMP	Time since the sensor was powered up	µs	uint32	4	0
RESERVED	Reserved field for future use	-	uint16	2	4
BUFFER	Raw magnetic calibration data buffer	-	uint8[]	16	6

SBG_ECOM_LOG_ODO_VEL (19)

This log provides the external velocity aiding expressed in meters per second, measured along the IMU/vehicle X axis (direction of travel).
This velocity can be sourced from various speed sensors, such as a quadrature/pulse odometer or integrated CAN bus vehicles odometer.

The log is asynchronous and is sent whenever new velocity aiding information is available, such as when an odometer pulse is detected.

• Message Name (ID): SBG_ECOM_LOG_ODO_VEL (19)
• Compatibility: INS capable products
• Firmware:
• Payload Size: 10 bytes

Field	Description	Unit	Format	Size	Offset
TIME_STAMP	Time since the sensor was powered up	µs	uint32	4	0
ODO_STATUS	Odometer velocity status (see ODO_STATUS)	-	uint16	2	4
ODO_VEL	Velocity along the odometer direction	m/s	float	4	6

Timestamp Considerations:
This log is asynchronous, with the timestamp indicating the actual time of the velocity data, rather than the time when the log was generated.
Consequently, the timestamp may slightly precede other data, such as IMU readings, that are sent simultaneously.

ODO_STATUS Definition

Bit	Name	Description
0	SBG_ECOM_ODO_REAL_MEAS	Set if the log is from a real pulse measurement, 0 for virtual ZUPT.
1	SBG_ECOM_ODO_TIME_SYNC	Set if the velocity information is correctly time-synchronized.

SBG_ECOM_LOG_AIR_DATA (36)

The airdata log provides barometric altitude above a reference level and true airspeed.
The altitude is typically measured using a barometer, while the true airspeed is obtained from a pitot tube.

By default, the altitude is referenced to a standard 1013.25 hPa zero level pressure.

This log serves both as an input and output.
It is sent by the unit when new internal airdata information is available.
It can also be used to inject external altitude and true airspeed aiding information.

Timestamp Considerations:
This log is asynchronous, with the timestamp indicating the actual time of the altitude/airspeed measurement, rather than the time when the log was generated.

When used as an input for external altitude aiding, the TIME_STAMP field may either represent an absolute time or a measurement delay, depending on the status flags.
The measurement delay allows the INS to calculate an absolute timestamp based on the reception time, transmission delay, and the specified delay.

• Message Name (ID): SBG_ECOM_LOG_AIR_DATA (36)
• Compatibility: ELLIPSE AHRS/INS
• Firmware:
• Payload Size: 26 bytes

Field	Description	Unit	Format	Size	Offset
TIME_STAMP / DELAY	Time since sensor was powered up or measurement delay	µs	uint32	4	0
AIRDATA_STATUS	Airdata information status (see AIRDATA_STATUS)	-	uint16	2	4
PRESSURE_ABS	Raw absolute pressure measured by the barometer sensor	Pa	float	4	6
ALTITUDE	Altitude computed from barometric altimeter	m	float	4	10
PRESSURE_DIFF	Raw differential pressure measured by the pitot tube	Pa	float	4	14
TRUE_AIRSPEED	True airspeed measured by the pitot tube	m/s	float	4	18
AIR_TEMPERATURE	Outside air temperature used for airspeed computations	°C	float	4	22

AIRDATA_STATUS Definition

Bit	Name	Description
0	SBG_ECOM_AIR_DATA_TIME_IS_DELAY	Set if TIME_STAMP represents a measurement delay instead of absolute time.
1	SBG_ECOM_AIR_DATA_PRESSURE_ABS_VALID	Set if the absolute pressure field is filled and valid.
2	SBG_ECOM_AIR_DATA_ALTITUDE_VALID	Set if the barometric altitude field is filled and valid.
3	SBG_ECOM_AIR_DATA_PRESSURE_DIFF_VALID	Set if the differential pressure field is filled and valid.
4	SBG_ECOM_AIR_DATA_AIRSPEED_VALID	Set if the true airspeed field is filled and valid.
5	SBG_ECOM_AIR_DATA_TEMPERATURE_VALID	Set if the outside air temperature field is filled and valid.

SBG_ECOM_LOG_DVL_BOTTOM/WATER_TRACK

This log records velocity data from a Doppler Velocity Log (DVL), either from bottom tracking or water tracking.
The timestamp indicates the actual time of the DVL velocity data, rather than being synchronized with the main loop.

• Message Name (ID): SBG_ECOM_LOG_DVL_BOTTOM_TRACK (29), SBG_ECOM_LOG_DVL_WATER_TRACK (30)
• Compatibility: INS capable products
• Firmware:
• Payload Size: 30 bytes

Field	Description	Unit	Format	Size	Offset
TIME_STAMP	Time since the sensor was powered up	µs	uint32	4	0
DVL_STATUS	DVL velocity status bitmask (see DVL_STATUS)	-	uint16	2	4
VELOCITY_X	Velocity in the X direction, DVL instrument frame	m/s	float	4	6
VELOCITY_Y	Velocity in the Y direction, DVL instrument frame	m/s	float	4	10
VELOCITY_Z	Velocity in the Z direction, DVL instrument frame	m/s	float	4	14
VELOCITY_QUALITY_X	Quality of the X velocity measurement	m/s	float	4	18
VELOCITY_QUALITY_Y	Quality of the Y velocity measurement	m/s	float	4	22
VELOCITY_QUALITY_Z	Quality of the Z velocity measurement	m/s	float	4	26

DVL_STATUS Definition

Bit	Name	Description
0	SBG_ECOM_DVL_VELOCITY_VALID	Set if the DVL measured a valid velocity
1	SBG_ECOM_DVL_TIME_SYNC	Set if the data is accurately timestamped using Sync In/Out

SBG_ECOM_LOG_DEPTH (47)

This log captures pressure and depth information from a subsea depth sensor.
The timestamp reflects the actual time of the depth measurement, rather than being synchronized with the main loop.

• Message Name (ID): SBG_ECOM_LOG_DEPTH (47)
• Compatibility: High Performance INS
• Firmware:
• Payload Size: 14 bytes

Field	Description	Unit	Format	Size	Offset
TIME_STAMP	Time since the sensor was powered up or measurement delay	µs	uint32	4	0
DEPTH_STATUS	Depth sensor status bitmask (see DEPTH_STATUS)	-	uint16	2	4
PRESSURE_ABS	Absolute water pressure measured	Pa	float	4	6
DEPTH	Measured depth, positive upward	m	float	4	10

DEPTH_STATUS Definition

Bit	Name	Description
0	SBG_ECOM_DEPTH_TIME_IS_DELAY	Set if the timestamp represents a delay instead of absolute time
1	SBG_ECOM_DEPTH_PRESSURE_ABS_VALID	Set if the pressure field is valid
2	SBG_ECOM_DEPTH_ALTITUDE_VALID	Set if the depth field is valid

SBG_ECOM_LOG_USBL (37)

This log retrieves the position information as determined by a USBL (Ultra-Short Baseline) beacon.
The timestamp indicates the actual time of the positioning data, rather than being synchronized with the main loop.

• Message Name (ID): SBG_ECOM_LOG_USBL (37)
• Compatibility: High Performance INS
• Firmware:
• Payload Size: 38 bytes

Field	Description	Unit	Format	Size	Offset
TIME_STAMP	Time since the sensor was powered up	µs	uint32	4	0
USBL_STATUS	USBL system status bitmask (see USBL_STATUS)	-	uint16	2	4
LATITUDE	Latitude in degrees, positive north	°	double	8	6
LONGITUDE	Longitude in degrees, positive east	°	double	8	14
DEPTH	Depth below mean sea level, positive down	m	float	4	22
LATITUDE_STD	1σ standard deviation of latitude accuracy	m	float	4	26
LONGITUDE_STD	1σ standard deviation of longitude accuracy	m	float	4	30
DEPTH_STD	1σ standard deviation of depth accuracy	m	float	4	34

USBL_STATUS Definition

Bit	Name	Description
0	SBG_ECOM_USBL_TIME_SYNC	Set if the USBL data is accurately time-synchronized
1	SBG_ECOM_USBL_POSITION_VALID	Set if the USBL data represents a valid 2D position
2	SBG_ECOM_USBL_DEPTH_VALID	Set if the USBL data has valid depth information

Note

USBL aiding is not currently supported by the INS filter. However, the unit can accept external USBL aiding data and log it for later post-processing.

Event Markers

SBG Systems products support multiple input and output events, facilitating precise timestamping and synchronization of various equipment.
For example, an electrical signal can timestamp the exact moment a picture is taken.

SBG Systems' INS can align their internal clock with GPS time, providing a reliable solution for synchronizing devices and measurements to a common clock.

SBG_ECOM_LOG_EVENT_X (In/Out)

The Event In/Out log is designed to efficiently timestamp events at up to 1 kHz, while being transmitted at a maximum rate of 200 Hz.
This log can report up to five events detected in the last 5 ms, minimizing transmission overhead.

Depending on the product options, input/output signals such as Sync A, B, C, D, and E may be available, each associated with a corresponding message.

Operating Principle

The TIME_STAMP field marks the time of the first event received in the last 5 ms.
Subsequent events in this window are recorded with time offsets, optimizing log size.

Additionally, SBG Systems products can generate output event markers, providing both an electrical sync out signal and a corresponding output log for precise timing.

Example:
If three events occur within 5 ms:

• The first event's time is stored in TIME_STAMP.
• The second event's time is TIME_STAMP + TIME_OFFSET_0.
• The third event's time is TIME_STAMP + TIME_OFFSET_1.

Unused time offset fields are set to 0, and EVENT_STATUS indicates which fields are valid.

• Message Name (ID): SBG_ECOM_LOG_EVENT_A (24), SBG_ECOM_LOG_EVENT_B (25), SBG_ECOM_LOG_EVENT_C (26), SBG_ECOM_LOG_EVENT_D (27), SBG_ECOM_LOG_EVENT_E (28), SBG_ECOM_LOG_EVENT_OUT_A (45), SBG_ECOM_LOG_EVENT_OUT_B (46)
• Compatibility: All products
• Firmware:
• Payload Size: 14 bytes

Field	Description	Unit	Format	Size	Offset
TIME_STAMP	Time since the sensor was powered up	µs	uint32	4	0
EVENT_STATUS	Status bitmask (see EVENT_STATUS)	-	uint16	2	4
TIME_OFFSET_0	Time offset for the second received event	µs	uint16	2	6
TIME_OFFSET_1	Time offset for the third received event	µs	uint16	2	8
TIME_OFFSET_2	Time offset for the fourth received event	µs	uint16	2	10
TIME_OFFSET_3	Time offset for the fifth received event	µs	uint16	2	12

EVENT_STATUS Definition

Bit	Name	Description
0	SBG_ECOM_EVENT_OVERFLOW	Set if events are received at a rate higher than 1 kHz
1	SBG_ECOM_EVENT_OFFSET_0_VALID	Set if at least two events have been received
2	SBG_ECOM_EVENT_OFFSET_1_VALID	Set if at least three events have been received
3	SBG_ECOM_EVENT_OFFSET_2_VALID	Set if at least four events have been received
4	SBG_ECOM_EVENT_OFFSET_3_VALID	Set if five events have been received

Note

The device can handle event markers at up to 1 kHz. Excessive events may overload the internal CPU, decreasing performance and reliability.

Warning

Never leave an activated Sync In signal unconnected, as noise on the line may trigger spurious events at high rates.