Virtex-4 RocketIO MGT User Guide www.xilinx.com 125UG076 (v4.1) November 2, 2008Clock CorrectionRTable 3-15 is an example of data 11-bit attribute setting, the character value, CHARISKvalue, and the parallel data interface, and how each corresponds with the other.CLK_COR_SEQ_1_MASK, CLK_COR_SEQ_2_MASK,CLK_COR_SEQ_LEN AttributesThese attributes are used to correctly define the clock correction sequences. TheCLK_COR_SEQ_LEN attribute defines the length of the clock correction action and is usedin conjunction with CLK_COR_SEQ_*_MASK attributes to define the length of thesequence match. Valid sequence lengths are 1, 2, 3, 4, and 8. In the case of 8 bytes, theCLK_COR_SEQ_2_USE must be set to FALSE. Table 3-16 shows the settings for a 2-byteclock correction sequence. Note that the CLK_COR_SEQ_1_MASK is set to indicate a2-byte sequence as well.Table 3-14: Definition of Clock Correction Sequence Bits 9-0RXDEC8B10BUSECLK_COR_8B10B_DERXINTDATAWIDTHCLK_COR_SEQ_*_*[10] CLK_COR_SEQ_*_*[9:8] CLK_COR_SEQ_*_*[7:0]0 0 32 1 XX Raw RXDATA[7:0]0 0 40 0 Raw RXDATA[9:8] Raw RXDATA[7:0]1 0 40 1 XX Raw RXDATA[7:0]1 0 40 0 Raw RXDATA[9:8] Raw RXDATA[7:0]1 1 40 1 XX 8B/10B Decoded RXDATA[7:0]1 1 40 0 RXDISPERR, RXCHARISK 8B/10B Decoded RXDATA[7:0]Table 3-15: Clock Correction Sequence/Data CorrelationAttribute Setting Character CHARISK TXDATA (hex)CLK_COR_SEQ_1_1 = 00110111100 K28.5 1 BCCLK_COR_SEQ_1_2 = 00010010101 D21.4 0 95CLK_COR_SEQ_1_3 = 00010110101 D21.5 0 B5CLK_COR_SEQ_1_4 = 00010110101 D21.5 0 B5Table 3-16: Clock Correction Mask Example Settings (No Mask)Attribute Setting DefinitionCLK_COR_SEQ_1_1 00110111100 Defines a K28.5.CLK_COR_SEQ_1_2 00010010101 Defines a D21.4.CLK_COR_SEQ_1_MASK 1100 Check compare first 2 bytes.CLK_COR_SEQ_LEN 2 Complete sequence is 2 bytes.
