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TCanMsg

A record for grouping all CAN message related data.

type TCanMsg = packed record
  Id: LongWord;
  Ext: Boolean;
  Len: Byte;
  Data: array [0..(CANMSG_FD_MAX_DATA_LEN-1)] of Byte;
  Flags : bitpacked record
    Fd: Boolean;
    Err: Boolean;
  end;
  Timestamp: QWord;
end;

Fields

Name Description
Id CAN message identifier. 0..$7FF for 11-bit CAN identifiers, 0..$1FFFFFFF for 29-bit CAN identifiers.
Ext True for a 29-bit CAN identifier, False for an 11-bit CAN identifier.
Len Number of data bytes inside the CAN message. 0..8 for CAN classic messages. 0..8, 12, 16, 20, 24, 32, 48 or 64 for CAN FD messages.
Data Array with message data bytes.
Flags Message related flags:
  Fd - True for a CAN FD message, False for a CAN classic message.
  Err - True if the message is an error frame, False for a data frame (only used internally).
Timestamp Timestamp in microseconds of when the CAN message was transmitted or received.
Example - Declaring and initializing a TCanMsg variable:
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procedure TForm1.BtnTransmitClick(Sender: TObject);
var
  TxMsg: TCanMsg;
begin
  TxMsg.Id := $123;         // Set the CAN message identifier
  TxMsg.Ext := False;       // Set the identifier type to 11-bit
  TxMsg.Flags.Fd := False;  // Configure the message as CAN classic
  TxMsg.Flags.Err := False; // CAN data frame
  TxMsg.Len := 2;           // Set the data length to 2 bytes
  TxMsg.Data[0] := $37;     // Set the value of data byte 0
  TxMsg.Data[1] := $A5;     // Set the value of data byte 1

  // Transmit the CAN message.
  CanSocket1.Transmit(TxMsg);
end;