UPGRADE YOUR BROWSER

We have detected your current browser version is not the latest one. Xilinx.com uses the latest web technologies to bring you the best online experience possible. Please upgrade to a Xilinx.com supported browser:Chrome, Firefox, Internet Explorer 11, Safari. Thank you!

AR# 18973

LogiCORE 10 Gigabit Ethernet MAC - What conditions will lead to the assertion of RX_BAD_FRAME and BAD_FRAME?

Description

General Description: 

What conditions lead to the assertion of BAD_FRAME in the RX_STATISTICS_VECTOR in the Gigabit Ethernet MAC core? Are the conditions the same for RX_BAD_FRAME?

Solution

The following conditions cause the assertion of BAD_FRAME: 

- FCS errors occur 

- Packets are shorter than 64 bytes (Undersize or Fragment frames) 

- Error codes occur during the packet 

- Terminate code group is corrupted 

- Jumbo frames are received when jumbo frames are not enabled 

- The Length/Type field is a "length", but the real length of the received frame does not match the value in the Length/Type field  

 

All of the above conditions also cause the assertion of RX_BAD_FRAME, which indicates to the client to drop the frame. 

 

When a Pause Control Frame passing the following checks is received, it is counted as GOOD_FRAME in the RX_STATISTICS_VECTOR but is flagged as RX_BAD_FRAME to the client: 

- The Destination Address field is matched against the MAC Control Multicast address or the configured Source Address for the MAC 

- The Length/Type field is matched against the MAC Control Type code 

 

Control Frames are the only instance when RX_BAD_FRAME does not match BAD_FRAME.

AR# 18973
Date Created 09/03/2007
Last Updated 05/16/2014
Status Archive
Type General Article