Flash Binary

There are different methods to flash binary. We use ST-Link or JLink to flash binary to stm32 microcontrollers.

To install stlink-tools, jlink and STM32CubeProgrammer, see installation and also setup.

1. Flash using ST-Link

Connect your ST-Link to your microcontroller:

- SWCLK of stlink to SWCLK of controller
- SWIO of stlink to SWIO of controller
- GND of stlink to GND of controller

If you want to provide power to controller using stlink, connect their 3V3.They are connected internally or through mini jumpers on the boards.

1.1. Flash using command

Run this commnad in Terminal.

# st-flash [--reset] write <build-directory/binaryfile.bin> <start-address>
st-flash write buid/BasicSetup.bin 0x8000000

Use --reset option to reset afetr flash. Change binary file name to your program name.

# STM32_Programmer_CLI -c port=SWD -w <build_directory>/<program_name>.bin 0x8000000
STM32_Programmer_CLI -c port=SWD -w build/BasicSetup.bin 0x8000000

Add -c port=SWD reset=SWrst at the end of line to reset after flash. Change binary file name to your program name.

Attention

To reset after flash, make sure that reset pin of st-link is connected to reset pin of microcontroller. Otherwise, it will not work and give error. In discovery board, it is connected by default.

You do not need to write the long commnad every time, you can add them in Makefile, CMakeLists.txt or create flash.sh.

1.2. Makefile setup for flasing using ST-Link

Add these at the bottom of Makefile.

flash: $(BUILD_DIR)/$(TARGET).bin
	st-flash write $(BUILD_DIR)/$(TARGET).bin 0x8000000

pflash: $(BUILD_DIR)/$(TARGET).bin
	CubeProgrammer -c port=SWD -w $(BUILD_DIR)/$(TARGET).bin 0x8000000

If you want to reset after flash, update to:

flash: $(BUILD_DIR)/$(TARGET).bin
	st-flash --reset write $(BUILD_DIR)/$(TARGET).bin 0x8000000

pflash: $(BUILD_DIR)/$(TARGET).bin
	CubeProgrammer -c port=SWD -w $(BUILD_DIR)/$(TARGET).bin 0x8000000 -c port=SWD reset=SWrst

Flash binary.
make flash
make pflash

1.2. CMakeLists.txt setup for flashing using ST-Link

Add these lines at the bottom of CMakeLists.txt.

# Flash target
add_custom_target(flash
    COMMAND st-flash write ${CMAKE_BINARY_DIR}/${CMAKE_PROJECT_NAME}.bin 0x8000000
    DEPENDS ${CMAKE_PROJECT_NAME}
    COMMENT "Flashing binary to microcontroller"
    WORKING_DIRECTORY ${CMAKE_BINARY_DIR}
)

# Flash target
add_custom_target(pflash
    COMMAND STM32_Programmer_CLI -c port=SWD -w ${CMAKE_BINARY_DIR}/${CMAKE_PROJECT_NAME}.bin 0x8000000
    DEPENDS ${CMAKE_PROJECT_NAME}
    COMMENT "Flashing binary to microcontroller"
    WORKING_DIRECTORY ${CMAKE_BINARY_DIR}
)

Flash binary by running this command from build folder after building binary.
make flash
make pflash

1.3. Bash script setup for flashing using ST-Link

Create flash.sh at project folder.
```
touch flash.sh
```

Add follwing lines.

flash.sh

#!/bin/bash

set +e

st-flash write buid/BasicSetup.bin 0x8000000

flash.sh

#!/bin/bash

set +e

STM32_Programmer_CLI -c port=SWD -w build/BasicSetup.bin 0x8000000

Change binary file name to your program name.

Make flash.sh executable.
```
chmod +x flash.sh
```
Flash binary.
```
./flash.sh
```

The most preferred method for Makefile is writting command in the Makefile and for CMake is creating flash.sh.

2. Flash using JLink

Connect your JLLink to your microcontroller:
- SWCLK of stlink to SWCLK of controller
- SWIO of stlink to SWIO of controller
- GND of stlink to GND of controller
- VREF of jlink to 3V3 of controller
Jlink does not provide power to controller. VREF is used to check the voltage logic only.

Create flash.sh file at your project folder.

flash.sh

#!/bin/bash

set +e

JLinkExe -if SWD -speed 4000 -autoconnect 1 -CommanderScript flash.jlink

Create flash.jlink file at your project folder.

flash.jlink

device STM32F103C6
r
h
loadbin build/<your_binary_filename>.bin, 0x08000000
r
g
exit

Change device name and binary filename.

Make flash.sh executable.
```
chmod +x flash.sh
```
Flash binary.
```
./flash.sh
```

There are also other methods to flash binary. You can use internal bootloader and USB to UART converter to flash binary using UART pins. To get into bootloader mode, you need to connect BOOT0 to 3V3 and reset the controller. Then you can use stm32flash or STM32CubeProgrammer to flash binary. Some microcontrollers supports internal USB bootloader. If not, you can also create USB bootloader. Then, you can use dfu-util to flash binary using USB. Making USB bootloader is a bit complex and need to be done carefully. It also consumes some flash memory. So, it is not recommended for small memory microcontrollers.