AVR Freaks

The linker attempts to place data in the first 64kB of a big AVR and the code at higher addresses.

In practice,  you have 200kB of data with 30kB code.   So most data is outside the 64kB address range.

// linker places this first e.g. < 64kB
const unsigned char lady_128x127x4_bmp[] PROGMEM = {
    ...
};
// linker places this section after the regular PROGMEM e.g. > 64kB
const unsigned char lady_128x127x8_bmp[] __attribute__((section(".fini2")))= {
    ...
};
// you can only access the first 64kB of Flash with xxxx_P() functions
// you can access ANY data with the xxxx_PF() functions

// you can only use pgm_get_far_address(x) at runtime

I would like to have an array of far pointers at compile time.

// all pointers are 16-bit i.e. < 64kB
const uint8_t *bmps[] = {
    lady_128x127x4_bmp,
    lady_128x127x8_bmp,
};

// I would like to specify 32-bit (or 24-bit) addresses
// this simply sign extends the 16-bit address into 32-bits
const uint_farptr bmps[] = {
    lady_128x127x4_bmp,
    lady_128x127x8_bmp,
};

// in an ideal world you could have a far modifier
const far uint8_t *bmps[] = {
    lady_128x127x4_bmp,
    lady_128x127x8_bmp,
};

There must be some sort of mechanism.   After all,  the linker is happy to put code above 64kB.   And you don't need to handle function pointers differently.

Yes,   I can write functions that accept farptr and calculate the farptr at runtime with pgm_get_faraddress().

But it would be a lot tidier if struct or array can be initialised at compile time.

Google finds this subject but I could not find the answer.

David.

Edit.   Added G++ to Title