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Altera_Forum
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14 years ago

TSE and EtherType = 0..45

There is one behaviour that is not described in TSE datasheets: the TSE will not properly forward an incoming ethernet frame to user application in case the frame type is in range 0 ... 45 (decimal). In this case, regradless the actual size of ethernet frame only the amount specified in frame type + 14 bytes are passed to user application, rest is cut.

But, when the frame type is > 45 the full frame, regardless of actual size, is passed to user.

This is a problem for some applications where the ether_type could be anything (random) and not linked to the actual size of frame.