The 8B/10B table includes special characters (K characters) that are often used for control functions. CH*_TXCTRL2 ports are used to indicate if data on TXDATA are K characters or regular data. The 8B/10B encoder checks received CH*_TXDATA bytes to match any K character if corresponding CH*_TXCTRL2 bit is driven High.
Figure 1. 8B10B Bit and Byte Ordering
