__MAP__ tells the compiler to reserve space, by advancing the 4 pointers. In all cases it must be a constant expression. There is no error checking, so the user is responsible for the validity of the values.
All of these values are byte values. For CODE sets the compiler program counter. CONST sets the pointer for constant strings and CONST arrays, it counts down from the end of Flash memory. Both of these addresses are byte addresses and are absolute.
DATA sets the pointer for INTEGER and SINGLE variables. STRING sets the pointer for arrays of BYTE, INTEGER or FLOAT and counts down from the end of the variable space. These are byte addresses, but are relative to the space that BASIC allocates for variables.
When used with no parameters, the compiler will report where the various pointers are left following the compile.
This allows you to reserve space for Flash Write , or for implimenting program overlays.
The values for the above map represent are based on the SuperPRO with 8.25 firmware.
The first program writes code to the first Flash sector then calls code in the second Flash sector
This program when run shows
Now overlay the second Flash sector with this program
Now when run it shows, and it shows the access to share_x was changed