Signal Properties

NI-XNET describes each signal in the database using several parameters, or properties. The NI-XNET Database Editor enables you to configure signals by editing signal properties. Available properties are as follows. Required properties are indicated with an asterisk (*):

  • Name—Signal name. This must be unique within the frame.
  • Type—Signal type:
    • Static–Signal that is contained in every frame transmitted.
    • Multiplexer–Signal that carries an identifier for multiplexed signals.
    • Multiplexed–Signal that is combined with other signals that share the same multiplexer identifier.
  • Mode Value—Value of the multiplexer signal for which the subframe for this signal becomes active.
  • Start Bit*—Starting position in the frame payload.
  • Number of Bits*—Signal length in number of bits in the frame payload.
  • Data Type*—Data type of the signal (Signed, Unsigned, IEEE Float). The signal data type determines how the bits of a signal must be interpreted to build a value.
  • Byte Order*—Order of bytes in the frame payload:
    • Little Endian–Bits are counted from the least significant bit to the highest address.
    • Big Endian–Bits are counted from the most significant bit to the lowest address.
  • Scaling Factor—The factor to convert the signal binary value to its physical value.
  • Scaling Offset—Offset to add to the scaled physical value of the signal. Used when converting bits in the frame payload (physical data) to and from scaled floating point units (binary representation).
  • Maximum—Largest possible signal value.
  • Minimum—Smallest possible signal value.
  • Default Value—Value read or written for the signal if no physical data are yet available.
  • Unit—Physical unit of the signal.
  • Bit Layout—Table indicating signal byte order in the frame payload. The Bit Table is displayed in Signal Properties, Frame Properties, and PDU Properties. Each column (y-axis) represents bit location, and each row (x-axis) represents an individual byte.
  • Comment—Text field for notes or comments related to the signal. This field can contain up to 65535 characters.