4. SDK Directory Structure

This chapter describes the directories and files of Nsing.N32G033_Library.1.3.0 based on its actual file tree. All paths are relative to the SDK root.

4.1 Top-Level Layout

📁 Names ending in / are directories
📄 All other names are files

Nsing.N32G033_Library.1.3.0/
├── .vscode/
│   ├── launch.json
│   ├── settings.json
│   └── tasks.json
├── firmware/
│   ├── CMSIS/
│   └── n32g033_std_periph_driver/
├── jlink/
│   └── flash.jlink
├── Middlewares/
│   ├── freertos/
│   └── N32_SelfTest_Library/
├── projects/
│   └── n32g033_EVAL/
└── N32G033 version history.txt

Relative path	Purpose
`firmware/`	Firmware library: CMSIS core and device support files, standard peripheral driver library
`Middlewares/`	Middleware: FreeRTOS kernel and the N32 self-test library
`projects/n32g033_EVAL/`	Evaluation board projects: board support, peripheral examples, and application projects
`jlink/flash.jlink`	J-Link Commander download script, called by the `download` target of the GCC project
`.vscode/`	VS Code GDB debug, build task, and editor settings
`N32G033 version history.txt`	SDK version history

4.2 Firmware Library

📁 firmware/CMSIS

core/ holds the Arm CMSIS-Core headers, of which Cortex-M0 projects use core_cm0.h; device/ holds the N32G033 device support files.

CMSIS/
├── core/
│   ├── cmsis_armcc.h
│   ├── cmsis_armclang.h
│   ├── cmsis_armclang_ltm.h
│   ├── cmsis_compiler.h
│   ├── cmsis_gcc.h
│   ├── cmsis_iccarm.h
│   ├── cmsis_version.h
│   ├── core_armv81mml.h
│   ├── core_armv8mbl.h
│   ├── core_armv8mml.h
│   ├── core_cm0.h
│   ├── core_cm0plus.h
│   ├── core_cm1.h
│   ├── core_cm23.h
│   ├── core_cm3.h
│   ├── core_cm33.h
│   ├── core_cm35p.h
│   ├── core_cm4.h
│   ├── core_cm7.h
│   ├── core_sc000.h
│   ├── core_sc300.h
│   ├── mpu_armv7.h
│   ├── mpu_armv8.h
│   └── tz_context.h
└── device/
    ├── startup/
    │   ├── startup_n32g033.s
    │   ├── startup_n32g033_EWARM.S
    │   ├── startup_n32g033_EWARM_ClassB.S
    │   └── startup_n32g033_gcc.s
    ├── n32g033.h
    ├── n32g033_conf.h
    ├── n32g033_flash.ld
    ├── system_n32g033.c
    └── system_n32g033.h

📁 firmware/n32g033_std_periph_driver

Standard peripheral driver library: inc/ holds the driver headers and src/ the implementations of the same name, one pair per driver module.

n32g033_std_periph_driver/
├── inc/
│   ├── misc.h
│   ├── n32g033_adc.h
│   ├── n32g033_comp.h
│   ├── n32g033_dbg.h
│   ├── n32g033_dma.h
│   ├── n32g033_exti.h
│   ├── n32g033_flash.h
│   ├── n32g033_gpio.h
│   ├── n32g033_hdiv.h
│   ├── n32g033_i2c.h
│   ├── n32g033_iwdg.h
│   ├── n32g033_opamp.h
│   ├── n32g033_pwr.h
│   ├── n32g033_rcc.h
│   ├── n32g033_spi.h
│   ├── n32g033_sqrt.h
│   ├── n32g033_tim.h
│   └── n32g033_uart.h
└── src/
    ├── misc.c
    ├── n32g033_adc.c
    ├── n32g033_comp.c
    ├── n32g033_dbg.c
    ├── n32g033_dma.c
    ├── n32g033_exti.c
    ├── n32g033_flash.c
    ├── n32g033_gpio.c
    ├── n32g033_hdiv.c
    ├── n32g033_i2c.c
    ├── n32g033_iwdg.c
    ├── n32g033_opamp.c
    ├── n32g033_pwr.c
    ├── n32g033_rcc.c
    ├── n32g033_spi.c
    ├── n32g033_sqrt.c
    ├── n32g033_tim.c
    └── n32g033_uart.c

Relative path	Purpose
`firmware/CMSIS/device/n32g033.h`	Device header: peripheral register structures, base addresses, and interrupt numbers
`firmware/CMSIS/device/system_n32g033.c`	System clock initialization; requires the `N32G033` macro, defaults to HSI at 64 MHz, and can be set to 32 MHz or 32 kHz through `SYSCLK_FREQ`
`firmware/CMSIS/device/n32g033_conf.h`	Includes all driver headers and defines `assert_param`
`firmware/CMSIS/device/startup/startup_n32g033.s`	Keil MDK-ARM startup file
`firmware/CMSIS/device/startup/startup_n32g033_EWARM.S`	IAR EWARM startup file
`firmware/CMSIS/device/startup/startup_n32g033_EWARM_ClassB.S`	IAR EWARM startup file for the ClassB self-test, used by `applications/ClassB_demo`
`firmware/CMSIS/device/startup/startup_n32g033_gcc.s`	GCC startup file
`firmware/CMSIS/device/n32g033_flash.ld`	GCC linker script
`firmware/n32g033_std_periph_driver/inc/misc.h`	NVIC and SysTick configuration functions, corresponding to the NVIC module in chapter 5
`firmware/n32g033_std_periph_driver/inc/n32g033_hdiv.h`	Hardware divider driver header
`firmware/n32g033_std_periph_driver/inc/n32g033_sqrt.h`	Square-root accelerator driver header

4.3 Projects Directory

projects/ contains only the n32g033_EVAL/ evaluation board directory, with board support, peripheral examples, and application projects.

📁 projects/n32g033_EVAL/bsp

Board support code, referenced by the examples through the bsp/inc include path.

bsp/
├── inc/
│   ├── delay.h
│   └── log.h
└── src/
    ├── delay.c
    ├── log.c
    └── print_remap.c

📁 projects/n32g033_EVAL/examples

Peripheral examples, organized into peripheral categories, each holding several example projects.

examples/
├── ADC/
├── COMP/
├── Cortex-M0/
├── DMA/
├── EXTI/
├── FLASH/
├── FreeRTOS/
├── GPIO/
├── HDIV/
├── I2C/
├── IWDG/
├── NVIC/
├── OPAMP/
├── PWR/
├── RCC/
├── SPI/
├── SQRT/
├── TIM/
└── UART/

📁 projects/n32g033_EVAL/applications

Application projects that demonstrate complete usage scenarios beyond the example directories.

applications/
├── ClassB_demo/
│   ├── EWARM/
│   ├── MDK-ARM/
│   ├── crc32_software.c
│   ├── crc32_software.h
│   ├── main.c
│   ├── main.h
│   ├── n32_cm0_it.c
│   └── n32_cm0_it.h
├── GCC_demo/
│   ├── GCC/
│   │   └── Makefile
│   ├── inc/
│   │   ├── main.h
│   │   └── n32g033_it.h
│   ├── src/
│   │   ├── main.c
│   │   └── n32g033_it.c
│   └── readme.txt
└── JumpToBOOT/
    ├── MDK-ARM/
    │   ├── JumpToBOOT.uvoptx
    │   └── JumpToBOOT.uvprojx
    ├── inc/
    │   ├── main.h
    │   └── n32g033_it.h
    ├── src/
    │   ├── main.c
    │   └── n32g033_it.c
    └── readme.txt

Relative path	Purpose
`projects/n32g033_EVAL/bsp/src/log.c`	Log UART initialization `log_init`: `UART1`, PA9 as TX and PA10 as RX, 115200 bps
`projects/n32g033_EVAL/bsp/inc/log.h`	`log_info`, `log_warning`, `log_error`, and `log_debug` macros, controlled by `LOG_ENABLE` and `LOG_LEVEL`
`projects/n32g033_EVAL/bsp/inc/delay.h`	SysTick delay functions `SysTick_Delay_Us` and `SysTick_Delay_Ms`
`projects/n32g033_EVAL/bsp/src/print_remap.c`	Standard I/O retarget functions `_write` and `_read`, which route `printf` output to the log UART
`projects/n32g033_EVAL/applications/ClassB_demo/`	ClassB self-test routine: runs `STL_InitRunTimeChecks` and `STL_DoRunTimeChecks` with static resources from `Middlewares/N32_SelfTest_Library`; provides Keil and IAR projects, and the Keil project includes `srecord_crc32.bat` and the srecord tools under `SREC/`
`projects/n32g033_EVAL/applications/JumpToBOOT/`	Jump from the user program to SYSTEM BOOT: after reset it prints a notice and stays in the user program, and a press on the PA4 key jumps to system memory; provides a Keil project only
`projects/n32g033_EVAL/applications/GCC_demo/`	LED blink GCC project: the `Makefile` defines `N32G033` and uses `startup_n32g033_gcc.s` and `n32g033_flash.ld`, with `all`, `clean`, `download`, and `debug` targets

4.4 Standard Structure of an Example

Every example directory contains source files, headers, a Keil project, an IAR project, and a readme. Take examples/GPIO/LedBlink/ as an example:

LedBlink/
├── EWARM/
│   ├── LedBlink.ewd
│   ├── LedBlink.ewp
│   └── LedBlink.eww
├── inc/
│   ├── main.h
│   └── n32g033_it.h
├── MDK-ARM/
│   ├── LedBlink.uvoptx
│   └── LedBlink.uvprojx
├── src/
│   ├── main.c
│   └── n32g033_it.c
└── readme.txt

Relative path	Purpose
`src/main.c`	Example main program: peripheral initialization and the main loop
`src/n32g033_it.c`	Interrupt service functions
`inc/main.h`, `inc/n32g033_it.h`	Example header and interrupt function declarations
`MDK-ARM/LedBlink.uvprojx`	Keil project, defining the `N32G033` and `USE_STDPERIPH_DRIVER` compile macros
`EWARM/LedBlink.eww`	IAR workspace
`readme.txt`	Chinese and English notes: function description, development environment (toolchain and supported parts), how to use (system configuration and usage), and cautions

Every example names its project files after the example itself (such as LedBlink.uvprojx and LedBlink.eww), and no example directory contains a GCC project. The following cases differ from the standard structure:

Case	Example	Structure
Paired sub-projects that each carry a readme	`UART/LIN/`, `UART/IrDA_Tx&Rx/`	The `LIN/` parent holds `LIN_Master/` and `LIN_Slave/`, and the `IrDA_Tx&Rx/` parent holds `LP_Transmit_Receive/` and `Transmit_Receive/`; each sub-project carries its own `src/`, `inc/`, `MDK-ARM/`, `EWARM/`, and `readme.txt`
Extra helper sources	`FreeRTOS/LED_Blink/`, `I2C/EEPROM/`, `SPI/SPI_FLASH/`, `UART/IrDA_Tx&Rx/`, `UART/LIN/`, `UART/MultiProcessor/`	Their `src/` also holds helper drivers such as `led.c`, `timer.c`, `i2c_eeprom.c`, `spi_flash.c`, `bsp_Tim_38K.c`, `lin_master.c`, `lin_slave.c`, `bsp_key.c`, and `bsp_led.c`

Examples reference firmware/ and bsp/ through relative paths. When you copy an example, keep it at its original level under projects/n32g033_EVAL/examples/<category>/, otherwise you must also update the header and source paths in the project.

4.5 Development Aids

Relative path	Purpose
`jlink/flash.jlink`	J-Link Commander script: reset, load `build/output.hex`, reset, run, and quit
`.vscode/launch.json`	`gdb-arm` debug configuration: connects `arm-none-eabi-gdb` to the GDB server on `localhost:2331`, loads the program, resets, and sets a breakpoint at `main`
`.vscode/tasks.json`	`make_debug` build task, running `make debug` in the GCC project directory
`.vscode/settings.json`	Editor settings and file associations
`projects/n32g033_EVAL/applications/GCC_demo/GCC/Makefile`	GCC build script: `all` produces `build/output.elf`, `.hex`, and `.bin`; `download` calls `JLink.exe` with device `N32G033x8` to run `jlink/flash.jlink`; `debug` starts `JLinkGDBServer.exe`

The working directory in .vscode/tasks.json is written as projects/n32g033_EVAL/examples/GPIO/Led_Blink/GCC, which does not match the example directory projects/n32g033_EVAL/examples/GPIO/LedBlink; .vscode/launch.json loads the ELF file through a fixed path and names a fixed GCC toolchain path, and the J-Link installation path in the Makefile is also a fixed value. Adjust these paths for your own environment before use.

Beyond the SDK, Nations Technologies also provides the Keil support pack, the IAR and J-Link device patches, the Flash programming algorithm package, and the initialization code generation tool; their names and versions are listed in the Documentation and Tool Navigation chapter.