MIP_SDK  v3.0.0-736-g212583cf
MicroStrain Communications Library for embedded systems
Macros | Functions | Variables
7-Series GNSS/INS Example [C]

Example setup program for the 3DM-GQ7-GNSS/INS, and 3DM-CV7-GNSS/INS using C. More...

Macros

#define WHEELED_VEHICLE_APPLICATION   false
 Enable configuration for wheeled-vehicle constraints. More...
 

Functions

static void log_callback (void *_user, const microstrain_log_level _level, const char *_format, va_list _args)
 Custom logging callback for MIP SDK message formatting and output. More...
 
static void capture_gyro_bias (mip_interface *_device)
 Captures and configures device gyro bias. More...
 
static void configure_gnss_message_format (mip_interface *_device, const uint8_t _gnss_data_descriptor_set)
 Configures message format for GNSS data streaming. More...
 
static void configure_filter_message_format (mip_interface *_device)
 Configures message format for filter data streaming. More...
 
static void configure_antenna_offset (mip_interface *_device, const mip_vector3f _antenna_offset, const uint8_t _antenna_id)
 Configures the GNSS antenna offset parameters for the device. More...
 
static void initialize_filter (mip_interface *_device)
 Initializes and resets the navigation filter. More...
 
static void display_gnss_fix_state (const mip_gnss_fix_info_data *_fix_info_array, const uint8_t _array_index)
 Displays the current GNSS fix state for a specific antenna when changes occur. More...
 
static void display_filter_state (const mip_filter_mode _filter_state)
 Displays the current filter state when changes occur. More...
 
static mip_timestamp get_current_timestamp ()
 Gets the current system timestamp in milliseconds. More...
 
static bool mip_interface_user_send_to_device (mip_interface *_device, const uint8_t *_data, size_t _length)
 Handles sending packets to the device. More...
 
static bool mip_interface_user_recv_from_device (mip_interface *_device, uint8_t *_buffer, size_t _max_length, mip_timeout _wait_time, bool _from_cmd, size_t *_length_out, mip_timestamp *_timestamp_out)
 Handles receiving packets from the device. More...
 
static void initialize_device (mip_interface *_device, serial_port *_device_port, const uint32_t _baudrate)
 Initializes and configures a MIP device interface. More...
 
static void terminate (serial_port *_device_port, const char *_message, const bool _successful)
 Handles graceful program termination and cleanup. More...
 
static void exit_from_command (const mip_interface *_device, const mip_cmd_result _cmd_result, const char *_format,...)
 Handles graceful program termination and command failure cleanup. More...
 

Variables

static const char * PORT_NAME = "/dev/ttyACM0"
 Set the port name for the connection (Serial/USB) More...
 
static const uint32_t BAUDRATE = 115200
 Set the baudrate for the connection (Serial/USB) More...
 
static const uint16_t SAMPLE_RATE_HZ = 1
 Streaming rate in Hz. More...
 
static const uint32_t RUN_TIME_SECONDS = 30
 Example run time. More...
 

Detailed Description

This example shows a basic setup to configure the navigation filter with GNSS heading, and GNSS position and velocity as the heading sources to stream filter data for the 3DM-GQ7-GNSS/INS, and 3DM-CV7-GNSS/INS devices using C. This is not an exhaustive example of all settings for those devices. If this example does not meet your specific setup needs, please consult the MIP SDK API documentation for the proper commands.

License

Macro Definition Documentation

◆ WHEELED_VEHICLE_APPLICATION

#define WHEELED_VEHICLE_APPLICATION   false

Function Documentation

◆ log_callback()

static void log_callback ( void *  _user,
const microstrain_log_level  _level,
const char *  _format,
va_list  _args 
)
static

Processes and formats log messages from the MIP SDK based on severity level. Routes messages to appropriate output streams - errors and fatal messages go to stderr while other levels go to stdout. Each message is prefixed with its severity level name.

Parameters
_userPointer to user data (unused in this implementation)
_levelLog message severity level from microstrain_log_level enum
_formatPrintf-style format string for the message
_argsVariable argument list containing message parameters

◆ capture_gyro_bias()

static void capture_gyro_bias ( mip_interface *  _device)
static
Parameters
_devicePointer to the initialized MIP device interface

◆ configure_gnss_message_format()

static void configure_gnss_message_format ( mip_interface *  _device,
const uint8_t  _gnss_data_descriptor_set 
)
static

Sets up GNSS data output by:

  1. Querying device base rate
  2. Validating desired sample rate against base rate
  3. Calculating proper decimation
  4. Configuring message format with:
    • Fix information
Parameters
_devicePointer to the initialized MIP device interface
_gnss_data_descriptor_setData descriptor set for the GNSS ID to configure

◆ configure_filter_message_format()

static void configure_filter_message_format ( mip_interface *  _device)
static

Sets up filter data output by:

  1. Querying device base rate
  2. Validating desired sample rate against base rate
  3. Calculating proper decimation
  4. Configuring message format with:
    • GPS timestamp
    • Filter status
    • LLH position
    • NED velocity
    • Euler angles
Parameters
_devicePointer to the initialized MIP device interface

◆ configure_antenna_offset()

static void configure_antenna_offset ( mip_interface *  _device,
const mip_vector3f  _antenna_offset,
const uint8_t  _antenna_id 
)
static

Sets up the physical antenna offset values relative to the device's reference point. The offset is specified in meters using a 3D vector:

  • X: forward/back
  • Y: left/right
  • Z: up/down
Parameters
_devicePointer to the initialized MIP device interface
_antenna_offsetAntenna offset to set
_antenna_idAntenna ID to configure the offset for
Note
Offset values are specific to physical device setup and may need to be adjusted based on actual antenna placement

◆ initialize_filter()

static void initialize_filter ( mip_interface *  _device)
static

Configures the navigation filter by:

  1. Enabling GNSS position and velocity aiding measurements
  2. Enabling dual-antenna GNSS heading aiding measurements
  3. Configuring filter initialization settings:
    • Setting initial position and velocity to zero
    • Enabling automatic position/velocity/attitude determination
    • Configuring dual-antenna kinematic alignment
  4. Resetting the filter to apply new settings
Parameters
_devicePointer to the initialized MIP device interface

◆ display_gnss_fix_state()

static void display_gnss_fix_state ( const mip_gnss_fix_info_data *  _fix_info_array,
const uint8_t  _array_index 
)
static

Outputs readable messages for GNSS fix state transitions:

  • 3D fix
  • 2D fix
  • Time-only fix
  • No fix
  • Invalid fix
  • RTK float
  • RTK fixed
  • Differential fix Also indicates whether the current fix is valid based on flag checks.
Parameters
_fix_info_arrayPointer to an array of GNSS fix information structures containing fix types and validity flags
_array_indexZero-based index into the fix info array identifying which GNSS receiver to report (0 = primary antenna, 1 = secondary antenna)

◆ display_filter_state()

static void display_filter_state ( const mip_filter_mode  _filter_state)
static

Outputs readable messages for filter state transitions:

  • Initialization mode
  • Vertical gyro mode
  • AHRS mode
  • Full navigation mode
Parameters
_filter_stateCurrent filter mode from the MIP device interface

◆ get_current_timestamp()

static mip_timestamp get_current_timestamp ( )
static

Provides basic timestamping using system time:

  • Returns milliseconds since Unix epoch
  • Uses timespec_get() with UTC time base
  • Returns 0 if time cannot be obtained
Note
Update this function to use a different time source if needed for your specific application requirements
Returns
Current system time in milliseconds since epoch

◆ mip_interface_user_send_to_device()

static bool mip_interface_user_send_to_device ( mip_interface *  _device,
const uint8_t *  _data,
size_t  _length 
)
static

Implements the MIP device interface send callback:

  • Extracts serial port from device user pointer
  • Validates connection state
  • Writes data buffer to serial port
Parameters
_deviceMIP device interface containing the connection
_dataBuffer containing packet data to send
_lengthNumber of bytes to send
Returns
True if send was successful, false otherwise

◆ mip_interface_user_recv_from_device()

static bool mip_interface_user_recv_from_device ( mip_interface *  _device,
uint8_t *  _buffer,
size_t  _max_length,
mip_timeout  _wait_time,
bool  _from_cmd,
size_t *  _length_out,
mip_timestamp *  _timestamp_out 
)
static

Implements the MIP device interface receive callback:

  • Extracts serial port from device user pointer
  • Validates connection state
  • Reads available data into provided buffer
  • Timestamps the received data
Parameters
_deviceMIP device interface containing the connection
_bufferBuffer to store received data
_max_lengthMaximum number of bytes to read
_wait_timeHow long to wait for data in milliseconds
_from_cmdWhether this read is from a command response (unused)
_length_outNumber of bytes actually read
_timestamp_outTimestamp when data was received
Returns
True if receive was successful, false otherwise

◆ initialize_device()

static void initialize_device ( mip_interface *  _device,
serial_port _device_port,
const uint32_t  _baudrate 
)
static

Performs a complete device initialization sequence:

  1. Sets up a MIP device interface with specified timeouts and callbacks
  2. Verifies device communication with a ping command
  3. Sets the device to idle mode to ensure reliable configuration
  4. Queries and displays detailed device information
  5. Loads default device settings for a known state
Parameters
_devicePointer to a MIP device interface to initialize
_device_portPointer to an initialized serial port for device communication
_baudrateSerial communication baudrate for the device

◆ terminate()

static void terminate ( serial_port _device_port,
const char *  _message,
const bool  _successful 
)
static

Handles graceful shutdown when errors occur:

  • Outputs provided error message
  • Closes device connection if open
  • Exits with appropriate status code
Parameters
_device_portSerial port connection to close
_messageError message to display
_successfulWhether termination is due to success or failure

◆ exit_from_command()

static void exit_from_command ( const mip_interface *  _device,
const mip_cmd_result  _cmd_result,
const char *  _format,
  ... 
)
static

Handles command failure scenarios:

  • Formats and displays an error message with command result
  • Closes device connection
  • Exits with failure status
Parameters
_deviceMIP device interface for the command that failed
_cmd_resultResult code from a failed command
_formatPrintf-style format string for error message
...Variable arguments for format string

Variable Documentation

◆ PORT_NAME

const char* PORT_NAME = "/dev/ttyACM0"
static

◆ BAUDRATE

const uint32_t BAUDRATE = 115200
static
Note
For native serial connections this needs to be 115200 due to the device default settings command Use mip_base_*_comm_speed() to write and save the baudrate on the device

◆ SAMPLE_RATE_HZ

const uint16_t SAMPLE_RATE_HZ = 1
static

◆ RUN_TIME_SECONDS

const uint32_t RUN_TIME_SECONDS = 30
static