# STM32 Development
###### tags: `stm32`

[TOC]

## Get Library (Code Generator)

### Why

- The reason we need to get libraries is because we want to simplify the process of setting register.
- Functions can help us interacte with hardware.
- Code generator can help us generate those function automatically and setup Makefile for us.

### Tools

#### STM32 Library

- Now There are 3 libraries for stm32: **HAL**, LL, SPL
- There difference and comparison can be found [here](https://itexp.blog.csdn.net/article/details/54613202).
- We choose HAL as our library because it is the easiest to use, despite its inefficiency.
- [HAL library introduction](https://itexp.blog.csdn.net/article/details/55213616)
- [HAL library official describtion for F4](https://www.st.com/resource/en/user_manual/dm00105879-description-of-stm32f4-hal-and-ll-drivers-stmicroelectronics.pdf)
- [HAL library F4 source code](https://github.com/STMicroelectronics/STM32CubeF4/tree/master/Drivers/STM32F4xx_HAL_Driver)
- [HAL library official describtion for F7](https://www.st.com/content/ccc/resource/technical/document/user_manual/45/27/9c/32/76/57/48/b9/DM00189702.pdf/files/DM00189702.pdf/jcr:content/translations/en.DM00189702.pdf)

#### Code Generator

- [**STM32CubeMX**](https://www.st.com/en/development-tools/stm32cubemx.html)
- [Reference Video](https://youtu.be/FkqQpBqkSns)

### Further Study

- Due the inefficiency of the HAL library, we can try using more low-level library like LL or directly use CMSIS, a library provide by ARM and it is the lowest library we can get.

## Editor

- We are going to use **VSCode** as the primary editor because it has great intellisense and also we can integrate debugger into. The latter will be discuss in the [Flash](#Flash) & [Debug](#Debug) section.

### Configuring VScode

- [Reference Video](https://youtu.be/jcy5TpbXfAY)

#### c_cpp_properties.json

{
    "env": {
        "arm_gcc_path": "/home/ben/stm32_tools/abe_build/builds/destdir/x86_64-pc-linux-gnu"
    },
    "configurations": [
        {
            "name": "Linux",
            "includePath": [
                "${workspaceFolder}/Core/Inc",
                "${workspaceFolder}/Drivers/STM32F4xx_HAL_Driver/Inc",
                "${workspaceFolder}/Drivers/CMSIS/Include",
                "${workspaceFolder}/Drivers/CMSIS/Device/ST/STM32F4xx/Include",
                "${arm_gcc_path}/arm-none-eabi/**",
                "${arm_gcc_path}/include/**",
                "${arm_gcc_path}/lib/gcc/arm-none-eabi/11.2.1/include/**",
                "${arm_gcc_path}/lib/gcc/arm-none-eabi/11.2.1/include-fixed/**"
            ],
            "defines": [
                "USE_HAL_DRIVER",
                "STM32F407xx"
            ],
            "compilerPath": "${arm_gcc_path}/bin/arm-none-eabi-g++",
            "cStandard": "gnu17",
            "cppStandard": "gnu++14",
            "intelliSenseMode": "linux-gcc-x64"
        }
    ],
    "version": 4
}

>Note: If you have install "Makefile Tools" extension and cannot configure, delete this line `"configurationProvider": "ms-vscode.makefile-tools"` in your "c_cpp_properties.json" file

## Compiler

- There are several compiler for compiling ARM chips. Details can be found [here](https://blog.csdn.net/ZCShouCSDN/article/details/89553323).
(other refer: https://youtu.be/imUiQkO9YHM?si=xaaTE8C6mMjiJRlM&t=142)

### GNU Arm Embedded Toolchain

- We are going to use [**GNU Arm Embedded Toolchain**](https://developer.arm.com/tools-and-software/open-source-software/developer-tools/gnu-toolchain/downloads) as our compier tool chain.

- The reason is because it is open source and free, and it matches the interface of gcc, which many of us are already familiar with. And also, it provides a good debugger tool, gdb, that can be integrade into many environment for debugging purpose.

#### Download Precompile Executable

- Look for keyword like `x86_64 Linux` and `arm-none-eabi)`

#### Install from Source

- If something go wrong and you cannot solve it, you can try install from source. This method has a lot of chance to solve most problems.

- There is a instruction in the "release note".

1. `wget https://raw.githubusercontent.com/git/git/master/contrib/workdir/git-new-workdir`
2. `sudo mv git-new-workdir /usr/local/bin`
3. `sudo chmod +x /usr/local/bin/git-new-workdir `
4. `git clone https://git.linaro.org/toolchain/abe.git`
5. `mkdir abe_build && cd abe_build`
6. `../abe/configure` (inside abe_build)
- If there is any package you don't have, install it.
7. `wget https://developer.arm.com/-/media/Files/downloads/gnu/11.2-2022.02/manifest/gcc-arm-arm-none-eabi-abe-manifest.txt`
- version dependent
9. `../abe/abe.sh --manifest gcc-arm-arm-none-eabi-abe-manifest.txt --build all`
- dependend on the last step
11. The executable will be locate in `abe_builds/destdir/x86_64-pc-linux-gnu/bin/`
12. Edit `~/.bashrc` and put `export PATH=$PATH:~/<the directory you keep the gnu_arm_toolchain>/abe_build/builds/destdir/x86_64-pc-linux-gnu/bin
` into it.

### Makefile Adjustment to compile C++

1. Add CPP_Source_file after C_Source_file

    CPP_SOURCES = \
    Core/Src/main.cpp

2. Change "binaries" section - add g++ complier and modify assembler

    ifdef GCC_PATH
    CC = $(GCC_PATH)/$(PREFIX)gcc

    #+++ CPP = $(GCC_PATH)/$(PREFIX)g++ 
    #+++ AS = $(GCC_PATH)/$(PREFIX)g++ -x assembler-with-cpp

    CP = $(GCC_PATH)/$(PREFIX)objcopy
    SZ = $(GCC_PATH)/$(PREFIX)size
    else
    CC = $(PREFIX)gcc

    #+++ CPP = $(PREFIX)g++
    #+++ AS = $(PREFIX)g++ -x assembler-with-cpp

    CP = $(PREFIX)objcopy
    SZ = $(PREFIX)size
    endif

3. Add CPP_Includes & CPP_Flags

    ...
    # CPP includes
    #+++ CPP_INCLUDES = $(C_INCLUDES)

    # compile gcc flags
    ASFLAGS = $(MCU) $(AS_DEFS) $(AS_INCLUDES) $(OPT) -Wall -fdata-sections -ffunction-sections

    CFLAGS += $(MCU) $(C_DEFS) $(C_INCLUDES) $(OPT) -Wall -fdata-sections -ffunction-sections

    #+++ CPPFLAGS = $(MCU) $(C_DEFS) $(CPP_INCLUDES) $(OPT) -Wall -fdata-sections -ffunction-sections

    ifeq ($(DEBUG), 1)
    CFLAGS += -g -gdwarf-2
    endif

    #+++ ifeq ($(DEBUG), 1)
    #+++ CPPFLAGS += -g -gdwarf-2
    #+++ endif

    # Generate dependency information
    CFLAGS += -MMD -MP -MF"$(@:%.o=%.d)"

    #+++ CPPFLAGS += -MMD -MP -MF"$(@:%.o=%.d)"

4. Add Linker Flag - "-specs=**nosys**.specs"

    LDFLAGS = $(MCU) -specs=nano.specs -specs=nosys.specs -T$(LDSCRIPT) $(LIBDIR) $(LIBS) -Wl,-Map=$(BUILD_DIR)/$(TARGET).map,--cref -Wl,--gc-sections

- If there is any error regarding to "lc_nano", delete the `-specs=nano.specs` line

> https://blog.csdn.net/zoomdy/article/details/100727279
> The source-install compiler seems to be lack of nano library.

5. Add Object file

    OBJECTS += $(addprefix $(BUILD_DIR)/,$(notdir $(CPP_SOURCES:.cpp=.o)))
    vpath %.cpp $(sort $(dir $(CPP_SOURCES)))

7. Add and modify compile command

    $(BUILD_DIR)/%.o: %.cpp Makefile | $(BUILD_DIR) 
        $(CPP) -c $(CPPFLAGS) -Wa,-a,-ad,-alms=$(BUILD_DIR)/$(notdir $(<:.cpp=.lst)) $< -o $@

    $(BUILD_DIR)/$(TARGET).elf: $(OBJECTS) Makefile
        $(CPP) $(OBJECTS) $(LDFLAGS) -o $@

#### Makefile Example

##########################################################################################################################
# File automatically-generated by tool: [projectgenerator] version: [3.16.0] date: [Sun May 08 20:39:50 CST 2022]
##########################################################################################################################

# ------------------------------------------------
# Generic Makefile (based on gcc)
#
# ChangeLog :
#	2017-02-10 - Several enhancements + project update mode
#   2015-07-22 - first version
# ------------------------------------------------

######################################
# target
######################################
TARGET = C_Test1


######################################
# building variables
######################################
# debug build?
DEBUG = 1
# optimization
OPT = -Og


#######################################
# paths
#######################################
# Build path
BUILD_DIR = build

######################################
# source
######################################
# C sources
C_SOURCES =  \
Core/Src/gpio.c \
Core/Src/usart.c \
Core/Src/stm32f4xx_it.c \
Core/Src/stm32f4xx_hal_msp.c \
Drivers/STM32F4xx_HAL_Driver/Src/stm32f4xx_hal_tim.c \
Drivers/STM32F4xx_HAL_Driver/Src/stm32f4xx_hal_tim_ex.c \
Drivers/STM32F4xx_HAL_Driver/Src/stm32f4xx_hal_uart.c \
Drivers/STM32F4xx_HAL_Driver/Src/stm32f4xx_hal_rcc.c \
Drivers/STM32F4xx_HAL_Driver/Src/stm32f4xx_hal_rcc_ex.c \
Drivers/STM32F4xx_HAL_Driver/Src/stm32f4xx_hal_flash.c \
Drivers/STM32F4xx_HAL_Driver/Src/stm32f4xx_hal_flash_ex.c \
Drivers/STM32F4xx_HAL_Driver/Src/stm32f4xx_hal_flash_ramfunc.c \
Drivers/STM32F4xx_HAL_Driver/Src/stm32f4xx_hal_gpio.c \
Drivers/STM32F4xx_HAL_Driver/Src/stm32f4xx_hal_dma_ex.c \
Drivers/STM32F4xx_HAL_Driver/Src/stm32f4xx_hal_dma.c \
Drivers/STM32F4xx_HAL_Driver/Src/stm32f4xx_hal_pwr.c \
Drivers/STM32F4xx_HAL_Driver/Src/stm32f4xx_hal_pwr_ex.c \
Drivers/STM32F4xx_HAL_Driver/Src/stm32f4xx_hal_cortex.c \
Drivers/STM32F4xx_HAL_Driver/Src/stm32f4xx_hal.c \
Drivers/STM32F4xx_HAL_Driver/Src/stm32f4xx_hal_exti.c \
Core/Src/system_stm32f4xx.c  

# CPP sources
CPP_SOURCES = \
Core/Src/main.cpp

# ASM sources
ASM_SOURCES =  \
startup_stm32f407xx.s


#######################################
# binaries
#######################################
PREFIX = arm-none-eabi-
# The gcc compiler bin path can be either defined in make command via GCC_PATH variable (> make GCC_PATH=xxx)
# either it can be added to the PATH environment variable.
ifdef GCC_PATH
CC = $(GCC_PATH)/$(PREFIX)gcc
CPP = $(GCC_PATH)/$(PREFIX)g++
AS = $(GCC_PATH)/$(PREFIX)g++ -x assembler-with-cpp
CP = $(GCC_PATH)/$(PREFIX)objcopy
SZ = $(GCC_PATH)/$(PREFIX)size
else
CC = $(PREFIX)gcc
CPP = $(PREFIX)g++
AS = $(PREFIX)g++ -x assembler-with-cpp
CP = $(PREFIX)objcopy
SZ = $(PREFIX)size
endif
HEX = $(CP) -O ihex
BIN = $(CP) -O binary -S
 
#######################################
# CFLAGS
#######################################
# cpu
CPU = -mcpu=cortex-m4

# fpu
FPU = -mfpu=fpv4-sp-d16

# float-abi
FLOAT-ABI = -mfloat-abi=hard

# mcu
MCU = $(CPU) -mthumb $(FPU) $(FLOAT-ABI)

# macros for gcc
# AS defines
AS_DEFS = 

# C defines
C_DEFS =  \
-DUSE_HAL_DRIVER \
-DSTM32F407xx


# AS includes
AS_INCLUDES = 

# C includes
C_INCLUDES =  \
-ICore/Inc \
-IDrivers/STM32F4xx_HAL_Driver/Inc \
-IDrivers/STM32F4xx_HAL_Driver/Inc/Legacy \
-IDrivers/CMSIS/Device/ST/STM32F4xx/Include \
-IDrivers/CMSIS/Include

# CPP includes
CPP_INCLUDES = $(C_INCLUDES)

# compile gcc flags
ASFLAGS = $(MCU) $(AS_DEFS) $(AS_INCLUDES) $(OPT) -Wall -fdata-sections -ffunction-sections

CFLAGS += $(MCU) $(C_DEFS) $(C_INCLUDES) $(OPT) -Wall -fdata-sections -ffunction-sections

CPPFLAGS = $(MCU) $(C_DEFS) $(CPP_INCLUDES) $(OPT) -Wall -fdata-sections -ffunction-sections

ifeq ($(DEBUG), 1)
CFLAGS += -g -gdwarf-2
endif

ifeq ($(DEBUG), 1)
CPPFLAGS += -g -gdwarf-2
endif

# Generate dependency information
CFLAGS += -MMD -MP -MF"$(@:%.o=%.d)"

CFLAGS += -MMD -MP -MF"$(@:%.o=%.d)"

#######################################
# LDFLAGS
#######################################
# link script
LDSCRIPT = STM32F407VETx_FLASH.ld

# libraries
LIBS = -lc -lm -lnosys 
LIBDIR = 
LDFLAGS = $(MCU) -specs=nano.specs -specs=nosys.specs -T$(LDSCRIPT) $(LIBDIR) $(LIBS) -Wl,-Map=$(BUILD_DIR)/$(TARGET).map,--cref -Wl,--gc-sections

# default action: build all
all: $(BUILD_DIR)/$(TARGET).elf $(BUILD_DIR)/$(TARGET).hex $(BUILD_DIR)/$(TARGET).bin


#######################################
# build the application
#######################################
# list of objects
OBJECTS = $(addprefix $(BUILD_DIR)/,$(notdir $(C_SOURCES:.c=.o)))
vpath %.c $(sort $(dir $(C_SOURCES)))
OBJECTS += $(addprefix $(BUILD_DIR)/,$(notdir $(CPP_SOURCES:.cpp=.o)))
vpath %.cpp $(sort $(dir $(CPP_SOURCES)))
# list of ASM program objects
OBJECTS += $(addprefix $(BUILD_DIR)/,$(notdir $(ASM_SOURCES:.s=.o)))
vpath %.s $(sort $(dir $(ASM_SOURCES)))

$(BUILD_DIR)/%.o: %.c Makefile | $(BUILD_DIR) 
	$(CC) -c $(CFLAGS) -Wa,-a,-ad,-alms=$(BUILD_DIR)/$(notdir $(<:.c=.lst)) $< -o $@

$(BUILD_DIR)/%.o: %.cpp Makefile | $(BUILD_DIR) 
	$(CPP) -c $(CPPFLAGS) -Wa,-a,-ad,-alms=$(BUILD_DIR)/$(notdir $(<:.cpp=.lst)) $< -o $@

$(BUILD_DIR)/%.o: %.s Makefile | $(BUILD_DIR)
	$(AS) -c $(CFLAGS) $< -o $@

$(BUILD_DIR)/$(TARGET).elf: $(OBJECTS) Makefile
	$(CPP) $(OBJECTS) $(LDFLAGS) -o $@
	$(SZ) $@

$(BUILD_DIR)/%.hex: $(BUILD_DIR)/%.elf | $(BUILD_DIR)
	$(HEX) $< $@
	
$(BUILD_DIR)/%.bin: $(BUILD_DIR)/%.elf | $(BUILD_DIR)
	$(BIN) $< $@	
	
$(BUILD_DIR):
	mkdir $@		

#######################################
# clean up
#######################################
clean:
	-rm -fR $(BUILD_DIR)
  
#######################################
# dependencies
#######################################
-include $(wildcard $(BUILD_DIR)/*.d)

#######################################
# flash
#######################################
flash: $(BUILD_DIR)/$(TARGET).bin
        STM32_Programmer_CLI -c port=swd -w $< 0x08000000 -v -rst

# *** EOF ***

### Integrate into VSCode

- tasks.json

{
    // See https://go.microsoft.com/fwlink/?LinkId=733558
    // for the documentation about the tasks.json format
    "version": "2.0.0",
    "tasks": [
        {
            "label": "Build",
            "group": "build",
            "type": "shell",
            "command": "make",
            "args": ["all", "-j4"]
        },
        {
            "label": "Clean",
            "group": "build",
            "type": "shell",
            "command": "make",
            "args": ["clean"]
        }
    ]
}

## Flash

### STM32CubeProg

- ST provide a program software: [**STM32CubeProg**](https://www.st.com/en/development-tools/stm32cubeprog.html)
1. Use to flash executable
2. check ROM memory
3. Update firmware
- [ST LINK is not in the DFU mode plesse restart it](https://www.796t.com/content/1545114008.html)
>1. 拔掉stlink
>2. 插上stlink
>3. 不要點其他的，直接點選ST-LINK->Firmware update

- [reference video](https://youtu.be/CI1BcIN7qC4)

### STM32ProgrammerCLI

- We are going to use its command line tool to integrate it into VSCode.

- Edit `~/.bashrc` and put `export PATH=$PATH:~/STMicroelectronics/STM32Cube/STM32CubeProgrammer/bin` into it.

- [Official Manual](https://www.st.com/resource/en/user_manual/dm00403500-stm32cubeprogrammer-software-description-stmicroelectronics.pdf)

#### Usage
1. Command: `STM32_Programmer_CLI -c port=swd -w <executable> 0x08000000 -v -rst`
- -c: connect to the chip
- -w: write to the chip (0x08000000 is the starting address of the ROM of STM32)
- -v: verify the program
- -rst: automatically reset after flash

2. Modify Makefile - Add make command

    #######################################
    # flash
    #######################################
    flash: $(BUILD_DIR)/$(TARGET).bin
	    STM32_Programmer_CLI -c port=swd -w $< 0x08000000 -v -rst

3. Integrate into VSCode

- add the following code into "tasks" block in task.json.

        {
            "label": "Flash",
            "group": "build",
            "type": "shell",
            "command": "make",
            "args": ["flash", "-j4"]
        }

## Debug

### Install "Cortex-Debug" extension

- [Github Page](https://github.com/Marus/cortex-debug)

### Install "STM32CubeIDE" to get ST-LINK GDB server

- [Official Website](https://www.st.com/en/development-tools/stm32cubeide.html)

### Add `launch.json` file

- add executable
- select servertype as "stlink"
- select interface as "swd"

- Example

{
    // Use IntelliSense to learn about possible attributes.
    // Hover to view descriptions of existing attributes.
    // For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
    "version": "0.2.0",
    "configurations": [
        {
            "name": "ST-Link Debug",
            "cwd": "${workspaceFolder}",
            "executable": "./build/CPP_Test.elf",
            "device": "STM32F407VE",
            "request": "launch",
            "type": "cortex-debug",
            "runToEntryPoint": "main",
            "servertype": "stlink",
            "interface": "swd"
        }
    ]
}

#### Bug Fixing

- If you cannot launch the debugger sucefully within VSCode, try run `arm-none-eabi-gdb --version` on your terminal to check whether the gdb is working properly.
- If encouter the error regarding to the lack of "libncursesw5", try `sudo apt install libncursesw5 libncursesw5-dev` to install the library.

### Further Study

- It seems that J-link & OpenOCD are other good tools but I haven't have the time to take a good look at it.

## Other Option

There are other option for us to program stm32, for example:

1. Keil uVision IDE
2. STM32 Cube IDE