CRASH (Crash Detection)

The AT@CRASH command is used to configure the parameters for crash detection. When the detection condition is met (the current acceleration in a direction is beyond the configured threshold), the device will send a crash alarm (Record 74H) and data packets (Record 75H and Record 76H) to the backend server.

Note: The default accelerometer recording is 100Hz and the fastest GNSS recording is 1 Hz.

Example:
AT@CRASH=gv500cna,,1,100,14,1,8,7,1,1,1,2,,,,,,012F$
+ACK:CRASH,123456789012345,8203,3,0,,012F,20210407101530,1234$
AT@CRASH?gv500cna,,0C37$
+QRY:CRASH,123456789012345,8203,3,0,1,1,,1,100,14,1,8,7,1,1,1,2,,,,,,0C37,20210407101530,1234$

Parts

Fields

Length (Byte)

Range/Format

Default

Head

Header

3

AT@

AT@

Command Word

5

CRASH

CRASH

Leading Symbol

1

=

=

Password

8-16

gv500cna

Body

Reserved

0

Mode

1

0, 1, 2

0

Sensor Frequency

<=3

100, 200 (Hz)

100

Crash Threshold

<=3

6 - 80 (*100 mg)

14

Record Sensor Data

1

0, 1

1

Sensor Time Before Crash

1

1-8 (*0.5 seconds)

8

Sensor Time After Crash

1

1-8 (*0.5 seconds)

7

Record GNSS Data

1

0-2

1

GNSS 0.2Hz Samples Before Crash

1

0-2 (*10)

1

GNSS 1Hz Samples Before Crash

1

0-2 (*10)

1

GNSS 1Hz Samples After Crash

1

0-2 (*10)

2

Reserved

0

Reserved

0

Reserved

0

Reserved

0

Reserved

0

Tail

Sequence Number

4

0000-FFFF (‘0’-‘9’, ‘A’-‘F’)

Tail

1

$

$

  • Mode

    • 0 - Disable this function.

    • 1 - Enable only when ignition on.

    • 2 - Enable always.

    Note: For Mode 2, the power consumption of the terminal will increase. In addition, if the crash event occurs when the terminal is sleeping, the terminal may not be able to provide complete data before the crash to the server.

  • Sensor Frequency

    Specifies the sampling frequency of the sensor.

  • Crash Threshold

    The threshold for crash threshold. The smaller the value, the easier it is to trigger a crash event.

  • Record Sensor Data

    Specifies whether need to record sensor data.

    • 0 - None. In this mode, the terminal will not record the sensor data for crash, and the Record 75H will not be generated.

    • 1 - Acceleration data. The terminal will record acceleration data for crash.

  • Sensor Time Before Crash

    How many seconds of sensor data before the climax of a crash event. The unit is 0.5 second. If the ‘Record Sensor Data’ is set to 0, then this parameter is invalid.

  • Sensor Time After Crash

    How many seconds of sensor data after the climax of a crash event. The unit is 0.5 second. If the ‘Record Sensor Data’ is set to 0, then this parameter is invalid.

  • Record GNSS Data

    Specifies whether need to record GNSS data.

    • 0 - None. In this mode, the terminal will not record the GNSS data for crash, and the Record 76H will not be generated.

    • 1 - Mini Location. The terminal will record GNSS data in Data 81 format.

    • 2 - Full Location. The terminal will record GNSS data in Data 82 format.

  • GNSS 0.2Hz Samples Before Crash

    How many pieces of 0.2Hz GNSS data before the climax of a crash event. If the ‘Record GNSS Data’ is set to 0, then this parameter is invalid.

  • GNSS 1Hz Samples Before Crash

    How many pieces of 1Hz GNSS data before the climax of a crash event. If the ‘Record GNSS Data’ is set to 0, then this parameter is invalid.

  • GNSS 1Hz Samples After Crash

    How many pieces of 1Hz GNSS data after the climax of a crash event. If the ‘Record GNSS Data’ is set to 0, then this parameter is invalid.