The message for carrier extend symbol is:
"The IEEE Std 802.3 has a 1Gbps Half Duplex “carrier extension” provision to allow the addition of non-data symbols to the end of frames that are less than slotTime bits in length so that the resulting transmission is at least one slotTime in duration.
NXP does not manufacture a SoC that supports 1Gbps-HD.
Therefore, the P5040 does not support Carrier Extension because 1GbE is only supported in Full Duplex mode.
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