Codewarrior 中的 .prm 文件（1）
要讨论单片机的地址映射，就必须要接触.prm文件，本篇的讨论基于 Codewarrior 5.0 编译器，单片机采用MC9S12XS128。
通过项目模板建立的新项目中都有一个名字为“project.prm”的文件，位于Project Settings->Linker Files文件夹下。一个标准的基于XS128的.prm文件起始内容如下：
.prm文件范例：
/* This is a linker parameter file for the MC9S12XS128 */
/*This file is setup to use the HCS12X core only.If you plan to also use the XGATE in your project, best create a new project with the'New Project Wizard' (File|New... menu in the CodeWarrior IDE) and choose the appropriateproject parameters.*/
NAMES /* CodeWarrior will pass all the needed files to the linker by command line. But here you may add your dditional files */
END
SEGMENTS /* here all RAM/ROM areas of the device are listed. Used in PLACEMENT below. All addresses are logical' */
/* Register space */
/* IO_SEG = PAGED 0x0000 TO 0x07FF; intentionally not defined */
/* non-paged RAM */
RAM = READ_WRITE DATA_NEAR 0x2000 TO 0x3FFF;
/* non-banked FLASH */
ROM_4000 = READ_ONLY DATA_NEAR IBCC_NEAR 0x4000 TO 0x7FFF;
ROM_C000 = READ_ONLY DATA_NEAR IBCC_NEAR 0xC000 TO 0xFEFF;
/* VECTORS = READ_ONLY 0xFF00 TO 0xFFFF; intentionally not defined: used for VECTOR commands below */
//OSVECTORS = READ_ONLY 0xFF10 TO 0xFFFF; /* OSEK interrupt vectors (use your vector.o) */
/* paged EEPROM 0x0800 TO 0x0BFF; addressed through EPAGE */
EEPROM_00 = READ_ONLY DATA_FAR IBCC_FAR 0x000800 TO 0x000BFF;
EEPROM_01 = READ_ONLY DATA_FAR IBCC_FAR 0x010800 TO 0x010BFF;
EEPROM_02 = READ_ONLY DATA_FAR IBCC_FAR 0x020800 TO 0x020BFF;
EEPROM_03 = READ_ONLY DATA_FAR IBCC_FAR 0x030800 TO 0x030BFF;
EEPROM_04 = READ_ONLY DATA_FAR IBCC_FAR 0x040800 TO 0x040BFF;
EEPROM_05 = READ_ONLY DATA_FAR IBCC_FAR 0x050800 TO 0x050BFF;
EEPROM_06 = READ_ONLY DATA_FAR IBCC_FAR 0x060800 TO 0x060BFF;
EEPROM_07 = READ_ONLY DATA_FAR IBCC_FAR 0x070800 TO 0x070BFF;
/* paged RAM: 0x1000 TO 0x1FFF; addressed through RPAGE */
/* RAM_FE = READ_WRITE 0xFE1000 TO 0xFE1FFF; intentionally not defined: equivalent to RAM: 0x2000..0x2FFF */
/* RAM_FF = READ_WRITE 0xFF1000 TO 0xFF1FFF; intentionally not defined: equivalent to RAM: 0x3000..0x3FFF */
/* paged FLASH: 0x8000 TO 0xBFFF; addressed through PPAGE */
PAGE_F8 = READ_ONLY DATA_FAR IBCC_FAR 0xF88000 TO 0xF8BFFF;
PAGE_F9 = READ_ONLY DATA_FAR IBCC_FAR 0xF98000 TO 0xF9BFFF;
PAGE_FA = READ_ONLY DATA_FAR IBCC_FAR 0xFA8000 TO 0xFABFFF;
PAGE_FB = READ_ONLY DATA_FAR IBCC_FAR 0xFB8000 TO 0xFBBFFF;
PAGE_FC = READ_ONLY DATA_FAR IBCC_FAR 0xFC8000 TO 0xFCBFFF;
/* PAGE_FD = READ_ONLY 0xFD8000 TO 0xFDBFFF; intentionally not defined: equivalent to ROM_4000 */
PAGE_FE = READ_ONLY DATA_FAR IBCC_FAR 0xFE8000 TO 0xFEBFFF;
/* PAGE_FF = READ_ONLY 0xFF8000 TO 0xFFBFFF; intentionally not defined: equivalent to ROM_C000 */
END
PLACEMENT /* here all predefined and user segments are placed into the SEGMENTS defined above. */
_PRESTART, /* Used in HIWARE format: jump to _Startup at the code start */
STARTUP, /* startup data structures */
ROM_VAR, /* constant variables */
STRINGS, /* string literals */
VIRTUAL_TABLE_SEGMENT, /* C++ virtual table segment */
//.ostext, /* eventually OSEK code */
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_FE, PAGE_FC, PAGE_FB, PAGE_FA, PAGE_F9, PAGE_F8;
//.stackstart, /* eventually used for OSEK kernel awareness: Main-Stack Start */
SSTACK, /* allocate stack first to avoid overwriting variables on overflow */
//.stackend, /* eventually used for OSEK kernel awareness: Main-Stack End */
PAGED_RAM, /* there is no need for paged data accesses on this derivative */
DEFAULT_RAM /* all variables, the default RAM location */
INTO RAM;
DISTRIBUTE DISTRIBUTE_INTO
ROM_4000, PAGE_FE, PAGE_FC, PAGE_FB, PAGE_FA, PAGE_F9, PAGE_F8;
CONST_DISTRIBUTE DISTRIBUTE_INTO
ROM_4000, PAGE_FE, PAGE_FC, PAGE_FB, PAGE_FA, PAGE_F9, PAGE_F8;
DATA_DISTRIBUTE DISTRIBUTE_INTO
RAM;
//.vectors INTO OSVECTORS; /* OSEK vector table */
END
ENTRIES /* keep the following unreferenced variables */
/* OSEK: always allocate the vector table and all dependent objects */
//_vectab OsBuildNumber _OsOrtiStackStart _OsOrtiStart
END
STACKSIZE 0x100 /* size of the stack (will be allocated in DEFAULT_RAM) */
/* use these definitions in plane of the vector table ('vectors') above */
VECTOR 0 _Startup /* reset vector: this is the default entry point for a C/C++ application. */
//VECTOR 0 Entry /* reset vector: this is the default entry point for an Assembly application. */
//INIT Entry /* for assembly applications: that this is as well the initialization entry point */