I am trying to connect rocket io with yet another ASIC, which send out data that are compliant with IEEE 802.3ae standard. But my effort has failed. When I debugging my design, I found that rocket IO core pop up an TXKERR error, when I input the standard idle K character 07 into it. So I read appendix B of ug024.pdf, and found that 07 is not a valid K character for rocket io. So how should I deal with this?