{HEAD ~ The double speed clock signal} has a frequency twice as large as {TAIL ~ the frequency} of the internal memory controller clock signal 
{ HEAD ~ The double speed clock signal } has a frequency twice as large as { TAIL ~ the frequency } of the internal memory controller clock signal
HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH