public void Add(DeveloperDataIdMessage mesg)
        {
            byte?index = mesg.GetDeveloperDataIndex();

            if (index == null)
            {
                return;
            }

            m_developerDataIdMessages[index.Value] = mesg;

            // Remove all fields currently associated with this developer
            var keysToRemove =
                m_fieldDescriptionMessages.Keys
                .Where(
                    x =>
                    x.DeveloperDataIndex ==
                    index)
                .ToList();

            foreach (var key in keysToRemove)
            {
                m_fieldDescriptionMessages.Remove(key);
            }
        }