I'm using the MC9S12GC64. Just recently the code size has grown above 32k, and therefor I have upgraded to Code Warrior V4.6 with a license to link 64k of code.
This is how my .prm file has looked up until now. I have only used the non banked ROM. (The RAM setup in Start12.c is according to the serial monitor example.)
...SEGMENTS RAM = READ_WRITE 0x3000 TO 0x3FFF; /* unbanked FLASH ROM */ ROM_4000 = READ_ONLY 0x4000 TO 0x7FFF; ROM_C000 = READ_ONLY 0xC000 TO 0xFEFF; /* banked FLASH ROM */ PAGE_3C = READ_ONLY 0x3C8000 TO 0x3CBFFF; PAGE_3D = READ_ONLY 0x3D8000 TO 0x3DBFFF;ENDPLACEMENT _PRESTART, STARTUP, ROM_VAR, STRINGS, VIRTUAL_TABLE_SEGMENT, DEFAULT_ROM, NON_BANKED, COPY INTO ROM_4000, ROM_C000; OTHER_ROM INTO PAGE_3D, PAGE_3C; DEFAULT_RAM INTO RAM;ENDSTACKSIZE 0x100
Now I obviously need to do something to be able to go above 32k. One way would be to use the banked ROM. I suppose I then would need to use pragma directives to move e.g. constants to page 3c and 3d, right? I have fiddled a lot with this but have not been able to get it to work. What do I need to do with registers like PPAGE etc. in the Start12.c file?? How do I use the pragma directives? Can I just define any code like this:
#pragma CODE_SEG OTHER_ROM // Banked
static const signed int myVar=....
#pragma CODE_SEG DEFAULT // back to non banked
Or have I completely misunderstood??
Also, I searched the forums here and found another idea: a linear mapping model that would allow for 48k of non banked memory. This would definately cover my needs and sounds very attractive and simple. However, I tried to add this to the .prm file:
ROM_8000 = READ_ONLY 0x8000 TO 0xBFFF;
I did manage to compile and link but have not got the code to run. Again, I read that it might be that this area are is not flashed??
If I could keep everything within non banked 48k of ROM, I think I would prefer that, but any help would be appreciated. There has been many postings about memory mapping but I fear that I might lack the basic understanding to use the information I have found so far.