TLK100: reverse polarity

Hi Jieun,

10BASE-T uses Manchester Encoding which is essentially an XOR of CLK and Data. Since our PHY's MDI is differential, whatever is on TRD_P is the exact opposite of TRD_M. You can imagine that if identifying polarify is very important when trying to decode here as if the PHY reads TRD_P as TRD_N, then the decoding would be messed up.

10BASE-TX uses MLT-3 which uses a pattern of {0, +1, 0, -1} and cycles through that matter whenever the data on the rising edge of clock is a '1'. If this is '0', then the data will not move. In this signaling scheme, what matters is the event of a transition to detect a '1', not where the transition goes.

Sincerely,

Gerome