The following conditions cause the assertion of
rx_axis_tlast_N[8] along with rx_axis_tuser = 1 signifying a
bad frame:- FCS errors is detected
- Packets are shorter than 64 bytes (undersize or fragment frames)
- Frames of length greater than the maximum transmission unit (MTU) Size programmed are received and MTU Size Enable Frames are enabled
- Any control frame that is received is not exactly the minimum frame length unless Control Frame Length Check Disable is set
- Received data stream contains error codes
The case of an unsuccessful frame reception (for example, a run frame or a
frame with an incorrect FCS) is shown in the following figure. In this situation, a 128 bit-wide
stream active on Client 2 is depicted. The bad frame is received but the signal
rx_axis_tkeep_userN[8] (ERR) is asserted to the client at the end of
the frame (cycle #8). It is the responsibility of the user logic to drop the data already
transferred for this frame.Figure 1.
AXI4-Stream Non-Segmented Receive
Frame with Errors
