{HEAD ~ The following function tables} describe {TAIL ~ the operation} of a grey level generator 2 for producing the 1/2 duty cycle grey level 
describe
{ HEAD ~ The following function tables } describe { TAIL ~ the operation } of a grey level generator 2 for producing the 1/2 duty cycle grey level
HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH