private Unit GetDictionaryNextValue(Unit unit)
        {
            var next = unit.NextValue();

            while (!AnalogDictionary.ContainsKey(next) && !DigitalDictionary.ContainsKey(next))
            {
                next = next.NextValue();
            }

            return(next);
        }
        private Unit GetDictionaryPrevValue(Unit unit)
        {
            var prev = unit.PrevValue();

            while (!AnalogDictionary.ContainsKey(prev) && !DigitalDictionary.ContainsKey(prev))
            {
                prev = prev.PrevValue();
            }

            return(prev);
        }