Why, oh why... (WinAVR const array question)

[havok1919]

...do I have to do:

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sprites[9].tileIndex=pgm_read_byte(&(ship_frames[p1_direction]));

in WinAVR instead of just:

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sprites[9].tileIndex=ship_frames[p1_direction];

ship_frames is:

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const unsigned char ship_frames[] PROGMEM={34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49};

I'm assuming this is just my WinAVR newbieness showing... No warning or anything to let you know something's hosed... It had me confused for a while, so maybe someone else will be saved by that line of code.

-Clay

[uze6666]

Yeah, I regularly forget that myself and curse when I can't understand the nonsense data that I read . That's my biggest gripe with the GCC compiler for AVR. They could have made that stuff automatic at compilation. But I've heard this compiler were never designed for Harvard-like architectures.

Anyhow, as you figured out, *any* data read from the ROM MUST use these macros. Otherwise you will read data from that address but in RAM and naturally get garbage.

Uze