How to extract bytes from CAN_FRAME..?

General Discussion
#1

Hi all.

Having a little trouble extracting bytes from a CAN_FRAME class.

Trying this…

CAN_FRAME ChalFrame;
CAN_FRAME RespFrame;

Can0.watchFor(0x00040020);

  if (Can0.available() > 0)
    {
      Can0.read(ChalFrame);

  // Split the Challenge into raw bytes

  ChalByte[0] = (ChalFrame & 0xFF000000)>>24;
  ChalByte[1] = (ChalFrame & 0x00FF0000)>>16;
  ChalByte[2] = (ChalFrame & 0x0000FF00)>>8;
  ChalByte[3] = (ChalFrame & 0x000000FF);

Gives error message “no match for ‘operator&’ (operand types are ‘CAN_FRAME’ and ‘unsigned int’)” in Arduino IDE.

I need to extract these bytes, modify them individually, then reassemble and send.

If you have any pointers please let me know!

Thanks

Joe

#2

Fixed thanks to Colin.

No need to use bit shifting.

 ChalByte[0] = ChalFrame.data.byte[0];

Is appropriate :slight_smile: