目标板：C2000的28335/28069
一、主要思路：
1、准备升级程序（相当于一个bootloader），作为上电首先运行的程序。进入升级程序，首先判断需不需要升级，需要升级，进入升级状态，通信完成新的主程序的接收，存入，升级成功后，进入主程序运行。
2、在主程序运行时，收到升级指令，标记升级标志，重启进入升级程序进去升级。
3、板子上电后，会调到flash启动的起始地址0x33FFF6（DSP28335），这个地址存放着程序的codestart的其实地址。所以，修改了0x33FFF6的存放的值，那么就能决定执行那一段程序。还可以通过汇编跳转指令直接跳转到程序codestart执行。
二、升级程序
1、具备能力：具备通信能力和Flash读写能力
2、准备：Flash API移植、上位机的升级配套程序；存储升级标志位的空间(外部EEPROM，不会随便擦除的内部Flash)
3、流程：接收->校验->烧写->跳转
三、升级步骤
1、数据接收：通过CAN/串口等方式接收数据。由于28335内存较小，不适合缓存大量的数据，这里是接收一部分数据，校验完成后烧写进Flash，再去接收一部分数据
2、数据解析：接收到的数据是hex格式的数据，所以需要解析才能放入对应的flash地址。但由于28335能力限制，这里采用先在上位机解析完成，采用先告知地址，然后发送数据的方式完成数据通信和传输。
3、校验：这里采用crc校验。
/*******************************************************Name : crc16*Function: crc校验16位*Params : data（UInt8 *）：待操作的数组 len:数据长度*Return : UInt16：返回CRC值 CRC校验码为2个字节高位在前*******************************************************/UInt16 crc16(Uint8 *data, UInt16 len){ UInt16 CRC = 0xFFFF; UInt8 j, TMP = 0; UInt8 i; for (i = 0; i < len; i++) { CRC ^= data[i]; for (j = 0; j < 8; j++) { TMP = CRC & 0x0001; CRC = CRC >> 1; if(TMP) CRC = CRC ^ 0xA001; } } return CRC;}
4、数据烧写flash：运用flash API提供的接收完成数据的烧写。这里要注意flash API必须运行在RAM中。
5、完成数据烧写后，需要跳转到主程序。一般采用汇编指令。汇编指令asm("LB 0xXXXXXX")或者汇编函数。
这里采用asm的方式，跳转地址为新应用程序的起始地址，这里必须规定每次跟新的新应用程序的起始地址必须固定。
asm(" LB 0x3xxxxx");
如果是使用变动的起始地址，则必须采用汇编函数，把地址作为参数传进函数。
四、主程序
1、接收升级指令后，能够标志升级状态。重启进入升级程序，进行判断，进而升级程序。
2、主程序运行后，升级状态标记为不用升级状态。
五、注意点
1、升级程序与主程序要严格分开，合理分配flash空间,附升级程序和主程序cmd大致分配空间。
主程序cmd文件/*********************************************************************** File: f28335_nonBIOS_flash.cmd -- Linker command file for non-DSP/BIOS* code with DSP in Boot to Flash boot mode.** History: 09/18/07 - original (D. Alter)**********************************************************************/
MEMORY{PAGE 0: /* Program Memory */ BEGIN_M0 : origin = 0x000000, length = 0x000002 /* Part of M0SARAM. Used for "Boot to M0" bootloader mode. */ FLASH_PROGRAMS : origin = 0x310000, length = 0x000010 /* On-chip FLASH */ FLASH_PROGRAM : origin = 0x310010, length = 0x01FFF0 /* On-chip FLASH */ ZONE7A : origin = 0x200000, length = 0x010000
CSM_RSVD : origin = 0x33FF80, length = 0x000076 /* Part of FLASH Sector A. Reserved when CSM is in use. */ BEGIN_FLASH : origin = 0x33FFF6, length = 0x000002 /* Part of FLASH Sector A. Used for "Jump to flash" bootloader mode. */ PASSWORDS : origin = 0x33FFF8, length = 0x000008 /* Part of FLASH Sector A. CSM password locations. */ ADC_CAL : origin = 0x380080, length = 0x000009 /* ADC_cal function in Reserved memory */ OTP : origin = 0x380400, length = 0x000400 /* 1Kw OTP */ IQTABLES : origin = 0x3FE000, length = 0x000B50 /* Part of Boot ROM */ IQTABLES2 : origin = 0x3FEB50, length = 0x00008C /* Part of Boot ROM */ FPUTABLES : origin = 0x3FEBDC, length = 0x0006A0 /* Part of Boot ROM */ BOOTROM : origin = 0x3FF27C, length = 0x000D44 /* 8Kw Boot ROM */ RESET : origin = 0x3FFFC0, length = 0x000002 /* part of Boot ROM */ FLASH_CONST : origin = 0x300000, length = 0x010000 PAGE 1 : /* Data Memory */ M0SARAM : origin = 0x000002, length = 0x0003FE /* 1Kw M0 SARAM */ M1SARAM : origin = 0x000400, length = 0x000400 /* 1Kw M1 SARAM */ DRAM : origin = 0x008000, length = 0x008000 PIEVECT : origin = 0x000D00, length = 0x000100 ZONE7B : origin = 0x210000, length = 0x010000// FLASH_DATA : origin = 0x330000, length = 0x008000 /* On-chip FLASH */}
SECTIONS{/*** Compiler Required Sections ***/ /* Program memory (PAGE 0) sections */ .text1 : {DSP2833x_CodeStartBranch.obj(.text)}> FLASH_PROGRAMS, PAGE = 0 .text2 : {*(.text)}> FLASH_PROGRAM, PAGE = 0 .cinit : > FLASH_PROGRAM, PAGE = 0 .const : > FLASH_PROGRAM, PAGE = 0 .econst : > FLASH_CONST, PAGE = 0 .pinit : > FLASH_PROGRAM, PAGE = 0 .reset : > RESET, PAGE = 0, TYPE = DSECT /* We are not using the .reset section */ .switch : > FLASH_PROGRAM, PAGE = 0 .cio : > FLASH_PROGRAM, PAGE = 0
/* Data Memory (PAGE 1) sections */ .bss : > DRAM, PAGE = 1 .ebss : > DRAM, PAGE = 1 .stack : > DRAM, PAGE = 1 .sysmem : > ZONE7B, PAGE = 1 .esysmem : > ZONE7B, PAGE = 1
/*** User Defined Sections ***/ codestart : > BEGIN_FLASH, PAGE = 0 /* Used by file CodeStartBranch.asm */ csm_rsvd : > CSM_RSVD, PAGE = 0 /* Used by file passwords.asm */ internalMemFuncs : > FLASH_PROGRAM, PAGE = 0 /* Used by file Xintf.c. Link to internal memory */ passwords : > PASSWORDS, PAGE = 0 /* Used by file passwords.asm */
/* Section secureRamFuncs used by file SysCtrl.c. */ ramfuncs : LOAD = FLASH_PROGRAM, PAGE = 0 /* Should be Flash */ RUN = ZONE7A, PAGE = 0 /* Must be CSM secured RAM */ LOAD_START(_RamfuncsLoadStart), LOAD_END(_RamfuncsLoadEnd), RUN_START(_RamfuncsRunStart)
/* Allocate ADC_cal function (pre-programmed by factory into TI reserved memory) */ .adc_cal : load = ADC_CAL, PAGE = 0, TYPE = NOLOAD}
/******************* end of file ************************/
升级程序cmd文件
/*********************************************************************** File: f28335_nonBIOS_flash.cmd -- Linker command file for non-DSP/BIOS* code with DSP in Boot to Flash boot mode.** History: 09/18/07 - original (D. Alter)**********************************************************************/
MEMORY{PAGE 0: /* Program Memory */ BEGIN_M0 : origin = 0x000000, length = 0x000002 /* Part of M0SARAM. Used for "Boot to M0" bootloader mode. */ FLASH_PROGRAM : origin = 0x330000, length = 0x005000 /* On-chip FLASH G*/ FLASH_PROGRAM1 : origin = 0x335000, length = 0x001000 /* On-chip FLASH G*/ FLASH_CONST : origin = 0x336000, length = 0x001000 /* On-chip FLASH G*/ ZONE7A : origin = 0x200000, length = 0x010000
CSM_RSVD : origin = 0x33FF80, length = 0x000076 /* Part of FLASH Sector A. Reserved when CSM is in use. */ BEGIN_FLASH : origin = 0x33FFF6, length = 0x000002 /* Part of FLASH Sector A. Used for "Jump to flash" bootloader mode. */ PASSWORDS : origin = 0x33FFF8, length = 0x000008 /* Part of FLASH Sector A. CSM password locations. */ ADC_CAL : origin = 0x380080, length = 0x000009 /* ADC_cal function in Reserved memory */ OTP : origin = 0x380400, length = 0x000400 /* 1Kw OTP */ IQTABLES : origin = 0x3FE000, length = 0x000B50 /* Part of Boot ROM */ IQTABLES2 : origin = 0x3FEB50, length = 0x00008C /* Part of Boot ROM */ FPUTABLES : origin = 0x3FEBDC, length = 0x0006A0 /* Part of Boot ROM */ BOOTROM : origin = 0x3FF27C, length = 0x000D44 /* 8Kw Boot ROM */ RESET : origin = 0x3FFFC0, length = 0x000002 /* part of Boot ROM */ PAGE 1 : /* Data Memory */ M0SARAM : origin = 0x000002, length = 0x0003FE /* 1Kw M0 SARAM */ M1SARAM : origin = 0x000400, length = 0x000400 /* 1Kw M1 SARAM */ DRAM : origin = 0x008000, length = 0x008000 PIEVECT : origin = 0x000D00, length = 0x000100 ZONE7B : origin = 0x210000, length = 0x010000 //FLASH_DATA : origin = 0x330000, length = 0x008000 /* On-chip FLASH B*/}
SECTIONS{
Flash28_API: { -lFlash28335_API_V210.lib(.econst) -lFlash28335_API_V210.lib(.text) } LOAD = FLASH_PROGRAM1, RUN = ZONE7A, LOAD_START(_Flash28_API_LoadStart), LOAD_END(_Flash28_API_LoadEnd), RUN_START(_Flash28_API_RunStart), PAGE = 0
/*** Compiler Required Sections ***/ /* Program memory (PAGE 0) sections */ .text : > FLASH_PROGRAM, PAGE = 0 .cinit : > FLASH_PROGRAM, PAGE = 0 .const : > FLASH_PROGRAM, PAGE = 0 .econst : > FLASH_CONST, PAGE = 0 .pinit : > FLASH_PROGRAM, PAGE = 0 .reset : > RESET, PAGE = 0, TYPE = DSECT /* We are not using the .reset section */ .switch : > FLASH_PROGRAM, PAGE = 0 .cio : > FLASH_PROGRAM, PAGE = 0
/* Data Memory (PAGE 1) sections */ .bss : > DRAM, PAGE = 1 .ebss : > DRAM, PAGE = 1 .stack : > DRAM, PAGE = 1 .sysmem : > ZONE7B, PAGE = 1 .esysmem : > ZONE7B, PAGE = 1
/*** User Defined Sections ***/ codestart : > BEGIN_FLASH, PAGE = 0 /* Used by file CodeStartBranch.asm */ csm_rsvd : > CSM_RSVD, PAGE = 0 /* Used by file passwords.asm */ internalMemFuncs : > FLASH_PROGRAM, PAGE = 0 /* Used by file Xintf.c. Link to internal memory */ passwords : > PASSWORDS, PAGE = 0 /* Used by file passwords.asm */
/* Section secureRamFuncs used by file SysCtrl.c. */ ramfuncs : LOAD = FLASH_PROGRAM, PAGE = 0 /* Should be Flash */ RUN = ZONE7A, PAGE = 0 /* Must be CSM secured RAM */ LOAD_START(_RamfuncsLoadStart), LOAD_END(_RamfuncsLoadEnd), RUN_START(_RamfuncsRunStart)
/* Allocate ADC_cal function (pre-programmed by factory into TI reserved memory) */ .adc_cal : load = ADC_CAL, PAGE = 0, TYPE = NOLOAD}
/******************* end of file ************************/
2、固定程序起始地址的方法为，codeStartBranch.asm的其实地址，即codestart的其实地址，这里使用
.text1 : {DSP2833x_CodeStartBranch.obj(.text)}> FLASH_PROGRAMS, PAGE = 0 .text2 : {*(.text)}> FLASH_PROGRAM, PAGE = 0
详见主程序cmd文件描述。
3、升级后会出现跳转到主程序，不能执行的情况，所以必须要提供一个方式，解决这个问题。这里做了几个处理：
（1）进入主程序后，再修改升级标志位
（2）启动升级程序后，未进入主程序前，留有可以与上位机通信方式，可以再次进入升级模式。
（3）启动升级程序后，必须接收到一个指令才跳转至主程序执行。