HHPOSR

         BIT#  15  14  13  12  11  10  09  08  07  06  05  04  03  02  01  00
                x   x   x   x   x   x   x   x  h8  h7  h6  h5  h4  h3  h2  h1

This the secondary beam counter for the faster mode, triggering the UHRES pointers & doing the comparisons for HBSTRT, HBSTOP, HTOTAL, HSSTRT, HSSTOP
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