Thanks Andy and Stefan for your valuable time ans knowledge sharing
Indeed both of you had some useful new idea to me.

I brought host side message to keyboard and keyboard side signals to host.I considered host ultimate priority by checking data and clock lines too.
i saw all 4 channels in my scope.but there is a bit difference between this tow signalling.
it seems i must buffer all bytes that host send to kb at pc side
then send it to kb side.
for example when num lock is pressed the command 0EDH follwed by a byte which set/reset num lock bit.
but now i send 0EDH first then send 02h!!!