FIX_POINT_BITS
cst->isqrt = (1UL<< FIX_POINT_BITS) * 7/10;
temp = (3ULL<< (FIX_POINT_BITS*2)) - (count * temp);
temp = (cst->isqrt * temp) >> (FIX_POINT_BITS + FIX_POINT_BITS - 8);
return t + ((cprms->interval * temp) >> FIX_POINT_BITS);