Based on your reply, I must support Erik's previous post that In that manner portability should not really be a concern, but a known deficit as Andy pointed out here http://8052.com/forum/read/174415 . Which as by everyone's argument that one should only code for themselves with their hardware and their compiler. Alas, sad, but true, unless someone can come up with a method that would fulfill the requirements without making the code illegible. However, as it stands, the code can be made portable by making the code illegible and with great effort. Even with this effort the code still might not be portable as