has drifted into the transition zone or a similar condition is reported via the srqin signal either of these conditions causes a shift request or signal 636 going high at which time selector gate 611 again chooses another optimum shfout state as the master makes the new choice the shfout command is implemented across all channels and transition zones are avoided again the master keeps this shfout until a transition zone condition is detected the shift request at signal 636 is clocked out to form srqout which allows this condition to be propagated to the master when the variable delay is set to the minimum or maximum settings and fref has drifted to where it needs to be retracted or extended further a data slip condition occurs this condition is detected again by zones defined by ck 0 when shfin 0 retraced and ck 4 when shfin 1 extended in this section we will set the system in motion and follow through dynamics of zone detection and the sync logic response also depending on the initial shfout choice the margins for skew and allowed drift is also discussed the master 39 s shfout is connected to all shfin 39 s we assume the system is again connected in a master slave configuration and that the sync logic of the slaves passes through their shift requests via the srqout to sqrin daisy chain the slaves 39 shfout are ignored and the sync logic of the master is analyzed since the rising edge of fref relative to ffrm is arbitrary we choose two extreme cases and move fref left and right and determine their margins in real life however fref is held constant and ffrm actually varies over environmental changes for.