If DON[n] == DON[n-1],
         AbsDon[n] = AbsDon[n-1]

      If (DON[n] > DON[n-1] and DON[n] - DON[n-1] < 32768),
         AbsDon[n] = AbsDon[n-1] + DON[n] - DON[n-1]

      If (DON[n] < DON[n-1] and DON[n-1] - DON[n] >= 32768),
         AbsDon[n] = AbsDon[n-1] + 65536 - DON[n-1] + DON[n]

      If (DON[n] > DON[n-1] and DON[n] - DON[n-1] >= 32768),
         AbsDon[n] = AbsDon[n-1] - (DON[n-1] + 65536 - DON[n])

      If (DON[n] < DON[n-1] and DON[n-1] - DON[n] < 32768),
         AbsDon[n] = AbsDon[n-1] - (DON[n-1] - DON[n])