stm32（三） STM32(STM32F217XX) 分段程序下载以及其运行原理

?????1.在STM32中经常出现IAP下载，我们通常采用的策略是把程序分成两段。 ??? (A段)运行其主程序并且判断是否需要进行IAP下载,以及IAP下载的程序。 ??? (B段)用户的程序。也可以说是通过IAP升级的程序。 ??? 通常我们把这两段程序分别存储在FLASH的不同的地址空间。 ??? 例如：STM32的flash的存储布局是: ??? name????????????? block bass address????? size ??? sector 0?????? 0x08000000 - 0x08003fff???? 16k ??? sector 1?????? 0x08004000 - 0x08007fff???? 16k ??? sector 2?????? 0x08000000 - 0x08003fff???? 16k ??? sector 3?????? 0x08004000 - 0x08007fff???? 16k ??? sector 4?????? 0x08000000 - 0x08003fff???? 64k ??? sector 5?????? 0x08004000 - 0x08007fff???? 128k ??? sector 6?????? 0x08000000 - 0x08003fff???? 128k ??? sector 7?????? 0x08004000 - 0x08007fff???? 128k ??? sector 8?????? 0x08000000 - 0x08003fff???? 128k ??? sector 9?????? 0x08004000 - 0x08007fff???? 128k ??? sector 10????? 0x08004000 - 0x08007fff???? 128k ??? sector 11????? 0x08004000 - 0x08007fff???? 128k ??? ??? system memory? 0x1fff0000 - 0x1fff77ff???? 30k ??? OTP??????????? 0x1fff7800 - 0x1fff7a0f???? 528b ??? Option bytes?? 0x1fffc000 - 0x1fffc00f???? 16b ? 我的做法是把： ??? sector 0 作为我的A段程序存储 ??? sector 1 以及以后的内容作为B段程序存储 ??? ? 2.在A段程序中要注意的是: ??? typedef void (*usercode)(void);//???????????????????????????? ??? usercode EnterApp;??????????????????????????????????????????? ??? int main()??????????????????????????????????????????????????? ??? {???????????????????????????????????????????????????????????? ??? ?SCB->VTOR = 0x08004000;//重新定位中断向量表???????????????????????? ??? ?EnterApp = (usercode)(*(unsigned int *)(0x08004000 + 0x04));//0x08004000这里存放的是第堆栈的地址 ??? ?EnterApp();//在这里调用第二段程序???????????????????????????????????????????????? ??? }????????????????????????????????