The case of an unsuccessful frame reception (for example, a runt
frame or a frame with an incorrect FCS) are shown in the following figures for
32-bit and 64-bit. In this case the bad frame is received and the signal rx_axis_tuser is asserted to the client at the end of
the frame. It is then the responsibility of the client to drop the data already
transferred for this frame.
The following conditions cause the assertion of rx_axis_tlast along with rx_axis_tuser = 1 signifying a bad frame:
- FCS errors occur
- Packets are shorter than 64 bytes (undersize or fragment frames)
- Frames of length greater than the maximum transmission unit (MTU) size programmed are received
- Any control frame that is received is not exactly the minimum frame length
- The XGMII data stream contains error codes