User´s Manual - I+ME ACTIA GmbH

Signed Integer
Note: The Signal (Data) Type Signed Integer is also known as Signed Numeric (SNM).
CAT allows the user to edit or remove already existing Signals assigned to Frames. The user can also
create new Signals using CAT.
CAT can recognize eight different types of signals and allows different formats. To edit or create a
Signed Integer Signal open the Signal Definition window shown below.
Note: If you edit a diagnostic signal assigned to a DPID you see
DPID: instead of Frame: and Byte is default '1'.
Format
A Signed Integer Signal can have three different Formats: Binary, Decimal or Hexadecimal. Only the
Decimal format foresees Resolution, Offset and Unit (see below).
Position in the Frame
Byte: Describes which Data Byte of the frame is the first one used for this signal. (Starting Byte) Bytes are
counted upwards:
Byte 0 means the signal could be maximal 4 Byte long
Byte 7 would mean that the signal must fit into this single (last) Byte.
Bit: Describes which Bit of the chosen Data Byte is the first one used for this signal. (Starting Bit) Bits are
counted downwards:
Bit 7 means the complete 8 Bits (7 – 0) of the chosen Byte will be used.
Bit 0 would mean to use only Bit 0 of the Byte and then to use Bit 7, 6, ... of the following Byte.
Length: Describes the absolute Length of the signal.
For a Signed Integer signal the length is always a multiple of 1 Bit up to maximal 32 Bits.
See also Data Byte/Bit presentation on the CAN bus.
Note: For DPID signals Byte 0 is already used. So the selectable starting bytes are Byte 1 to 7.
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