FAQ copy

How to establish a Bluetooth connection with your device?

The device works as a slave so it accepts Bluetooth connections. You can make Bluetooth connections with your smartphone, portable computer or any other Bluetooth enabled device using RFcomm Protocol (SPP – Serial Port Profile).

I find the Radio Event option amazing. What is the frequency I can send a “Radio Event” to the VJ SDK data logger?

There is no specific frequency. The radio event can be sent to the device whenever you want.

If I press the PushButton for an event marking, does the system sends that message over the Bluetooth stream?

Yes, when the device receives one PushButton event it registers in the SD Card and sends it over Bluetooth stream.

What is the range of the accelerometer?

The range of the accelerometer is 8bits resolution (SByte) with ±4g.

What is the sampling frequency of the accelerometer?

The sampling frequency of tri-axial accelerometer is 10Hz.

What is the sampling frequency of the ECG ? Can I change it?

The ECG has a 500Hz sampling frequency. Now, is not possible to change it. In the next version you will be able to change the sampling frequency of the ECG.

What is VitalJacket SDK?

A tool to provide all stream control parameters (Fs, Gain, xGsens, etc.), Modes Configuration + Recording; RTC; Pushbutton (on BT stream and SD Card)

  • App Windows for test and data acquisition
  • App Android
  • Tools for data export: ECG wave, R-R (ms), QRS position (samples), Accelerometer (X,Y,Z)
  • Windows DLL for QRS detect
Why does the VJ SDK stops sending data after aprox. 2 seconds of operation?

The VJ device stops sending data after 2 seconds to save battery energy. To receive ECG stream it should send to the device the message ’0xFF’ every 2 seconds.

Why should we use VitalJacket SDK?

To facilitate VJ integration for R&D projects, new prototypes and products To provide developers a new Software Development Kit and API for different programming environments with drivers and sample code To allow VJ configuration trough a simple messaging protocol/ Mode switching to enhance its adaptability

Why the box does not send any data when I connect to it ?

When establishing a connection, the device is on energy saving mode. To receive ECG stream it should send to the device the message ’0xFF’ every 2 seconds.