CCS中的CMD文件解析

xyz549040622

Guru 65885 points

CMD主要是用来分配rom和ram空间用的,它告诉链接程序怎样计算地址和分配空间.所以不同的芯片就有不同大小的rom和ram.放用户程序的地方也不尽相同.所以要根据芯片进行修改.分两部分.MEMORY和SECTIONS.

MEMORY

{ PAGE 0 ..........

PAGE 1.........

}

SECTIONS

{

.vectors .................

.reset .................

................

}

MEMORY是用来指定芯片的rom和ram的大小和划分出几个区间.PAGE 0 对应rom，PAGE 1对应ram。PAGE里包含的区间名字与其后面的参数反映了该区间的起始地址和长度.

SECTIONS：在程序里添加段名.XXXX(如.vectors.)用来指定该段名以下，另一个段名以上的程序(属于PAGE0)或数据(属于PAGE1)放到“>”符号后的空间名字所在的地方。下面给出一个简单的例子：

MEMORY

{

PAGE 0: VECS: origin = 00000h, length = 00040h

LOW: origin = 00040h, length = 03FC0h

SARAM: origin = 04000h, length = 00800h

B0: origin = 0FF00h, length = 00100h

PAGE 1: B0: origin = 00200h, length = 00100h

B1: origin = 00300h, length = 00100h

B2: origin = 00060h, length = 00020h

SARAM: origin = 08000h, length = 00800h

}

SECTIONS

{

.text : { } > LOW PAGE 0

.cinit : { } > LOW PAGE 0

.switch : { } > LOW PAGE 0

.const : { } > SARAM PAGE 1

.data : { } > SARAM PAGE 1

.bss : { } > SARAM PAGE 1

.stack : { } > SARAM PAGE 1

.sysmem : { } > SARAM PAGE 1

}

CMD文件由三部分组成：(1) 输入输出定义；(2) MEMORY命令；(3) SECTION命令。

输入/输出定义：这一部分，可以通过ccs的“Build Option........”菜单设置

。obj 链接的目标文件

。lib 链接的库文件

。map 生成的交叉索引文件

。out 生成的可执行代码

MEMORY命令：描述系统实际的硬件资源

SECTION命令：描述“段”如何定位

下面给出一个例子：

-c

-o hello.out

-m hello.map

-stack 100

-l rts2xx.lib

MEMORY

{

PAGE 0: VECT:origin=0x8000,length 0x040

PAGE 0: PROG:origin=0x8040,length 0x6000

PAGE 1: DATA:origin=0x8000,length 0x400

}

SECTIONS

{

.vextors >VECT PAGE 0

.text >PROG PAGE 0

.bss >DATA PAGE 1

.const >DATA PAGE 1

}

存储模型说明：

.cinit 存放程序中的变量初值和常量

.const 存放程序中的字符常量、浮点常量和用const声明的常量

.switch 存放程序中switch语句的跳转地址表

.text 存放程序代码

.bss 为程序中的全局和静态变量保留存储空间

.far 为程序中用far声明的全局和静态变量保留空间

.stack 为程序系统堆栈保留存储空间，用于保存返回地址、函数间的参数传递、存储局部变量和保存中间结果

.sysmem 用于程序中的malloc 、calloc 、和realoc 函数动态分配存储空间.text可执行代码

9 年多前

xyz549040622 9 年多前

Guru 65885 points

其实TIVA系列中的.cmd文件是比较简单的，以TM4C123中的一个例子为例，启动文件如下

/******************************************************************************
 *
 * uart_echo_ccs.cmd - CCS linker configuration file for uart_echo.
 *
 * Copyright (c) 2012-2014 Texas Instruments Incorporated.  All rights reserved.
 * Software License Agreement
 * 
 * Texas Instruments (TI) is supplying this software for use solely and
 * exclusively on TI's microcontroller products. The software is owned by
 * TI and/or its suppliers, and is protected under applicable copyright
 * laws. You may not combine this software with "viral" open-source
 * software in order to form a larger program.
 * 
 * THIS SOFTWARE IS PROVIDED "AS IS" AND WITH ALL FAULTS.
 * NO WARRANTIES, WHETHER EXPRESS, IMPLIED OR STATUTORY, INCLUDING, BUT
 * NOT LIMITED TO, IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE APPLY TO THIS SOFTWARE. TI SHALL NOT, UNDER ANY
 * CIRCUMSTANCES, BE LIABLE FOR SPECIAL, INCIDENTAL, OR CONSEQUENTIAL
 * DAMAGES, FOR ANY REASON WHATSOEVER.
 * 
 * This is part of revision 2.1.0.12573 of the EK-TM4C123GXL Firmware Package.
 *
 *****************************************************************************/

--retain=g_pfnVectors

/* The following command line options are set as part of the CCS project.    */
/* If you are building using the command line, or for some reason want to    */
/* define them here, you can uncomment and modify these lines as needed.     */
/* If you are using CCS for building, it is probably better to make any such */
/* modifications in your CCS project and leave this file alone.              */
/*                                                                           */
/* --heap_size=0                                                             */
/* --stack_size=256                                                          */
/* --library=rtsv7M3_T_le_eabi.lib                                           */

/* The starting address of the application.  Normally the interrupt vectors  */
/* must be located at the beginning of the application.                      */
#define APP_BASE 0x00000000
#define RAM_BASE 0x20000000

/* System memory map */

MEMORY
{
    /* Application stored in and executes from internal flash */
    FLASH (RX) : origin = APP_BASE, length = 0x00040000
    /* Application uses internal RAM for data */
    SRAM (RWX) : origin = 0x20000000, length = 0x00008000
}

/* Section allocation in memory */

SECTIONS
{
    .intvecs:   > APP_BASE
    .text   :   > FLASH
    .const  :   > FLASH
    .cinit  :   > FLASH
    .pinit  :   > FLASH
    .init_array : > FLASH

    .vtable :   > RAM_BASE
    .data   :   > SRAM
    .bss    :   > SRAM
    .sysmem :   > SRAM
    .stack  :   > SRAM
}

__STACK_TOP = __stack + 256;

其他微控制器

其他微控制器论坛

CCS中的CMD文件解析