With embedded type of compilers the concept of the compiler invoking the "const" key word attribute to push variables into the NV storage (i.e. code area) of the MCU is a common adaptation. On the other hand, as Andy and others are quick to point out, there is no sure fire expectation that all compilers will work like that and as such it is extremely necessary to be fully familiar with your chosen tool set. And of course that should include reading the manual and reading all available support information for your tool set.

In the world of attention confined to 8052s there is still surely variation on this matter. If one expands the view to include a broader field of view then even more variation can be seen!! I have seen some implementations that come with ready made "kits" that are adapted for certain evaluation board environments wherein the kit piles layers of definitions and macros on top the standard underlying compiler. Some of these are a hopeless mess and one needs to use even more care. I find this interesting because the use of these software environment "kits" often attract implementers that are new to the embedded development field and become quickly messed up even though the intention of the "kit" is meant to be just the opposite.

The overall "teachable moment" here is to never trust or assume anything and become as close to fully informed about what you are doing (and working with) as possible.

Michael Karas