Transmit and receive a 64 byte CAN FD message at 500 KHz and 1 or 2 MHz: 
• Initialize FlexCAN and Message Buffer 4 to receive a message 
• Transmit one frame using Message Buffer 0 
• Loop:◦If Message Buffer 4 received message flag is set, read message
◦If Message Buffer 0 transmit done flag is set, transmit another message 

