The test bench performs the additional task of checking the destination address and source address of the frame in the following way:
- A fifth frame is pushed into the GMII/MII or RGMII receiver interface.
- The address filter looks at the DA/SA fields of each frame.
- If there is a mismatch between the DA/SA field of a frame and the 12-byte value the address filter has been pre-programmed with (in the AXI4-Lite state machine), then the frame is dropped.
- By default only the fifth frame is dropped because of this mismatch.