topic Re: Configuring MC9S12C64 Flash in S12 / MagniV Microcontrollers

Configuring MC9S12C64 Flash

pirate — Wed, 21 May 2008 02:55:45 GMT

The Microcontroller is MC9S12C64.

I am trying to program the MC9S12C64 flash but sometimes i get fixup overflow interrupt linker errors. I think the reason for that is the division of flash into blocks...addresses 0x4000 to 0x7FFF and 0xC000 to 0xFFFF are unpaged flash.... 0x8000 to 0xBfff is paged flash i want to use this whole range from 0x4000 to 0xFFFF as contiguous memory ..

how can i do it?

attached is the prm file...

Re: Configuring MC9S12C64 Flash

JimDon — Thu, 29 Oct 2020 09:02:14 GMT

I belive I have tried this and I think this works.
Just make sure PPAGE never gets changed.

Code:

SEGMENTS      ROM_8000      = READ_ONLY     0x8000 TO   0xBFFF;PLACEMENT  INTO  ROM_4000, ROM_8000, ROM_C000;

Re: Configuring MC9S12C64 Flash

pirate — Wed, 21 May 2008 07:27:04 GMT

I tried the method you suggested Jim but it still doesnot work. I am working with the linker settings in the project.........if you come to think of anything please let me know...

Thanks!!

Re: Configuring MC9S12C64 Flash

kef — Wed, 21 May 2008 12:48:00 GMT

Not CW guru, but I think that first of all you should make sure you are using small memory model, -Ms compiler switch, also small memory model libraries.

Then you should simply define single ROM segment

ROM = READ_ONLY 0x4000 TO 0xFEFF;

and change placement from

      DEFAULT_ROM, NON_BANKED,             /* runtime routines which must not be banked */
      COPY                    /* copy down information: how to initialize variables */
                              /* in case you want to use ROM_4000 here as well, make sure
                                 that all files (incl. library files) are compiled with the
                                 option: -OnB=b */
                        INTO ROM_C000/*, ROM_4000*/;

      OTHER_ROM         INTO PAGE_3C, PAGE_3D                  ;

DEFAULT_ROM, NON_BANKED,
COPY, OTHER_ROM

INTO ROM;