> BTW, I have realized that I was compiling for the default target, not > PIC16. Now, I'm getting some linker errors. I'm attaching the sources, > you can test it just with > # make > > I have commented out "puts" and "#include <assert.h>" and two assertions. > But I still get the following: > > [EMAIL PROTECTED]:~/Desktop/chess/firstchess/pic16$ make > sdcc firstchess.c -mpic16 -o firstChess
You are compiling for the default pic18f452, which may or not be what you want. Select the desired target chip with -mpic16 -p18f6720 (replace 6720 with your device code). > message: using default linker script "/usr/share/gputils/lkr/18f452.lkr" > warning: relocation of section "udata_firstchess_7" failed, relocating > to a shared memory location > error: linker script has no definition that matches the type of > section "udata_firstchess_7" > make: *** [all] Error 1 > > Any idea?? Thanks! Yes: You are out of memory, and even if the device had enough memory, you fail to respect the data banking scheme of the PICs (BSR register). 1) You allocate the HIST hist[6000] array of 48000 bytes; the 18f452 only has 6 banks of 256 bytes ==> 1536 bytes of memory. 2) The 18f6720 has 15 banks of 256 bytes of memory ==> 3840 bytes, which is all the PIC architecture can address (16 bank is split into access bank and SFRs and not available for general use). 3) Even if your array was the only data structure and was only 257 bytes in size, this error would occur still. The data memory is organized in banks of 256 bytes; no single object can be longer than that (has to do with BANKSEL directives and compiler internal assumptions about each structure/array residing completely in a single bank). In short, you must cut down the hist structure to (say) HIST hist[32], or modify the .lkr file to create a huge bank to accommodate *only* this array (you would have to make sure that other objects allocated to that superbank do not cross 256-byte boundaries, which you cannot do ==> problem in the linker rather than the compiler). Even then I cannot guarantee that the array access works as expected in all cases (it should, but such a setup is highly unusual and untested). Such problems caused my initial doubts on playing chess on a microcontroller. Knowing that you want to use PICs, I cannot see how to solve them: Other devices (8051-derivatives) have external memory, which might be useful in this case (if they can address 64 kB of memory), but with PICs I can only think of manually attached memory via 2 or more 8 bit ports for addresses and data, SPI, ... Good luck, Raphael ------------------------------------------------------------------------- This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ _______________________________________________ Sdcc-user mailing list Sdcc-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/sdcc-user
