STM32L01 series microcontrollers are programmed via serial port (ISP)

The official ISP software (serial port burning software) FlashLoader Demonstrator does not support the stm32l01 series of microcontrollers. So how can we use the serial port to burn the program for this type of microcontroller through the serial port? 

I recently did a project that required this, so I studied this method and shared it with those who need it. To prepare the tools, you only need the mcuisp (also known as flymcu) software and the serial port assistant. 

Provide mcuisp software for lazy people mcuisp 

After my experiment, mcuisp can program this microcontroller but cannot erase the chip. Later, I found that the erase instruction of this chip is different. Students who are interested can read this document AN3155 (USART protocol used in the STM32 bootloader) and search it on Baidu. 

So our task now is to find a way to erase this chip and then download it through the mcuisp software (my idea is that it is okay to use the existing tools directly after knowing the principle). The AN3155 document introduces the usage of each instruction in detail. We mainly read the erase instruction part 

This chip supports Extended Erase Memory Command, but it does not support the advanced commands in this command, so if you want to erase this chip, you must use the most troublesome step. Erase page by page. My chip has 16k flash and each page has 128b, so there are a total of 128 pages that need to be erased. If you send commands one by one, at least 129 commands are required. So I used Qt to write a serial port host computer to help me complete this tedious process. I am not very proficient in using Qt and basically have not seen the threshold. Here is a solution. If you want to learn from it, please reply below this post and I can share the main code. 

In addition, the chip I use supports user-defined boot options, so it is more convenient to use with this. The code for selecting the boot area is as follows:

void BOOTCONF_User() //Determine where the system is booted from. If booting from systemflsh, change the option byte to boot from //Flash program memory

{

    HAL_StatusTypeDef status = HAL_OK;

     uint32_t tmp = 0U, tmp1 = 0U;

    if (LL_SYSCFG_GetBootMode() == LL_SYSCFG_BOOTMODE_SYSTEMFLASH)

    {

        tmp = OB->USER & (~0XE000);

        tmp |= (1u << 15);

        tmp1 = (~tmp) << 16;

        tmp |= tmp1;

        HAL_FLASH_OB_Unlock();

        status = FLASH_WaitForLastOperation(FLASH_TIMEOUT_VALUE);

        {

            OB->USER = tmp;

            FLASH_WaitForLastOperation(FLASH_TIMEOUT_VALUE);

        }       

        HAL_FLASH_OB_Launch();

        HAL_FLASH_OB_Lock();

    }

}

void BOOTCONF_System()//How to trigger your own definition after receiving the programming instruction to let the chip enter the system bootloader

{

    HAL_StatusTypeDef status = HAL_OK;

    uint32_t tmp = 0U, tmp1 = 0U;

    tmp = OB->USER | 0X00E000;

    tmp &= 0X00BFFF;

    tmp1 = (~tmp) << 16;

    tmp |= tmp1;

    HAL_FLASH_OB_Unlock();

    FLASH_WaitForLastOperation(FLASH_TIMEOUT_VALUE);

    {

        OB->USER = tmp;

        FLASH_WaitForLastOperation(FLASH_TIMEOUT_VALUE);

    }

    HAL_FLASH_OB_Launch();

    HAL_FLASH_OB_Lock();

}