Re: MII preamble size


"glen herrmannsfeldt" <gah@xxxxxxxxxxxxxxxx> wrote in message
news:m7WdnWZxNrvMMiranZ2dnUVZ_u3inZ2d@xxxxxxxxxxxxxx
Marris wrote:
"Woody Brison" <woody.brison@xxxxxxxxx> wrote in message
news:6757dbab-7f63-4b25-af4c->

I'm designing a PHY, does it need to handle a random
size preamble or should it reject packets that don't have
the exact size specified for the transmit case?

PHY's don't check preamble so there is no need to worry about this.

Well, it needs to check enough to find the start of
the data packet. That shouldn't be hard, though.

-- glen


It depends. For the 100BASE-X PCS the original poster is interested in, the
PHY will be looking at tx_en from the MII to determine transmit packet start
and for receive packets looking for JK symbols to determine packet start.


.

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