Quick Startup

Use Nuclei SDK in Nuclei Studio

Caution

If you are looking for Nuclei 100 series such as N100 support, you need to switch to master_n100 or nuclei_n100 branch of this repository to try it out.

If you are evaluating Nuclei CPU, in future released nuclei_gen, you will be able to use the generated Nuclei SDK, please see Usage.

For Nuclei SDK 0.6.0 version and later ones, please use Nuclei Studio 2024.06 or Nuclei RISC-V Toolchain/OpenOCD/QEMU 2024.06.

From Nuclei Toolchain 2023.10, both gnu and llvm toolchain are provided, and toolchain prefix changed from riscv-nuclei-elf- to riscv64-unknown-elf-, and 0.5.0 SDK release will only support this 2023.10 or later toolchain.

If you want to learn about how to use Nuclei Tools(IDE,Toolchain,Qemu,OpenOCD,XlModel), please checkout https://doc.nucleisys.com/nuclei_tools.

If you want to report issues and see application note when using Nuclei Tools or Nuclei Studio, please checkout https://github.com/Nuclei-Software/nuclei-studio.

Now the nuclei-sdk released versions are deeply integrated with Nuclei Studio IDE via menu RV-Tools -> NPK Package Management, and you can directly create nuclei-sdk project in Nuclei Studio IDE Menu File -> New Nuclei RISC-V C/C++ Project.

You can download Nuclei Studio IDE from Nuclei Download Center, and follow Nuclei_Studio_User_Guide.pdf to learn how to use it.

But if you want to use latest source code of Nuclei SDK, please follow the rest part of this guide to build and run using Nuclei SDK Build System in Makefile.

Setup Tools and Environment

To start to use Nuclei SDK, you need to install the following tools:

From 2020.10 release version of Nuclei Studio, you can directly use the prebuilt tools provided in Nuclei Studio(strongly suggested), please following Use Prebuilt Tools in Nuclei Studio.

Use Prebuilt Tools in Nuclei Studio

Since 2020.10 release version of Nuclei Studio, you just need to download the Nuclei Studio IDE from Nuclei Download Center for your development OS, and no need to do the following steps below, the prebuilt tools are already included.

For example:

In Windows, if you have extracted the Nuclei Studio IDE to D:\Software\NucleiStudio_IDE_202406, then you can find the prebuilt tools in D:\Software\NucleiStudio_IDE_202406\NucleiStudio\toolchain.
In Linux, if you have extracted the Nuclei Studio IDE to /home/labdev/NucleiStudio_IDE_202406, then you can find the prebuilt tools in /home/labdev/NucleiStudio_IDE_202406/NucleiStudio/toolchain.

You can also update tools located in the Nuclei Studio prebuilt tools toolchain by downloading newer version from Nuclei Tools and replace it.

Get and Setup Nuclei SDK

The source code of Nuclei SDK is maintained in Github and Gitee.

We mainly maintained github version, and gitee version is mirrored, just for fast access in China.
Check source code in Nuclei SDK in Github or Nuclei SDK in Gitee according to your network status.
Stable version of Nuclei SDK is maintained in master version, if you want release version of Nuclei SDK, please check in Nuclei SDK Release in Github.

Here are the steps to clone the latest source code from Github:

Make sure you have installed Git tool, see https://git-scm.com/download/
Then open your terminal, and make sure git command can be accessed
Run git clone https://github.com/Nuclei-Software/nuclei-sdk nuclei-sdk to clone source code into nuclei-sdk folder
Note
- If you have no access to github.com, you can also use command git clone https://gitee.com/Nuclei-Software/nuclei-sdk nuclei-sdk to clone from gitee.
- If you have no internet access, you can also use pre-downloaded nuclei-sdk code, and use it.
- If the backup repo is not up to date, you can import github repo in gitee by yourself, see https://gitee.com/projects/import/url
Create tool environment config file for Nuclei SDK
Note

If you want to use Terapines ZCC toolchain, you can download it from https://www.terapines.com/, or use Nuclei Studio >= 2024.06, a Terapines ZCC Lite version is integrated in <NucleiStudio>/toolchain/zcc folder, and you also need to add extra PATH into your environment, like this:
- Windows: execute set PATH=\path\to\zcc\bin;%PATH% in windows cmd terminal before run Nuclei SDK
- Linux: execute set PATH=/path/to/zcc/bin:$PATH in linux shell terminal before build Nuclei SDK
- Windows
  If you want to use Nuclei SDK in Windows Command Prompt terminal, you need to create setup_config.bat in nuclei-sdk folder, and open this file your editor, and paste the following content, assuming you followed Setup Tools and Environment, and prebuilt tools located in D:\Software\NucleiStudio_IDE_202406\NucleiStudio\toolchain, otherwise please use your correct tool root path.
  set NUCLEI_TOOL_ROOT=D:\Software\NucleiStudio_IDE_202406\NucleiStudio\toolchain
  If you want to use Nuclei SDK in Windows PowerShell terminal, you need to create a setup_config.ps1 in nuclei-sdk folder, and edit this file with content below if your prebuilt tools are located in D:\Software\NucleiStudio_IDE_202406\NucleiStudio\toolchain:
  $NUCLEI_TOOL_ROOT="D:\Software\NucleiStudio_IDE_202406\NucleiStudio\toolchain"
- Linux
  Create setup_config.sh in nuclei-sdk folder, and open this file your editor, and paste the following content, assuming you followed Setup Tools and Environment and prebuilt tools located in /home/labdev/NucleiStudio_IDE_202406/NucleiStudio/toolchain, otherwise please use your correct tool root path.
  NUCLEI_TOOL_ROOT=/home/labdev/NucleiStudio_IDE_202406/NucleiStudio/toolchain

Build, Run and Debug Sample Application

Assume you have followed steps in Get and Setup Nuclei SDK to clone source code and create files below:

setup_config.bat for run in Windows Command Prompt terminal
setup_config.ps1 for run in Windows PowerShell terminal
setup_config.sh for run in Linux Bash terminal

To build, run and debug application, you need to open command terminal in nuclei-sdk folder.

For Windows users, you can open Windows Command Prompt terminal and cd to nuclei-sdk folder, then run the following commands to setup build environment for Nuclei SDK, the output will be similar as this screenshot Setup Build Environment for Nuclei SDK in Windows Command Prompt:
```
1setup.bat
2echo %PATH%
3where riscv64-unknown-elf-gcc openocd make rm
4make help
```
Setup Build Environment for Nuclei SDK in Windows Command Prompt
For Linux users, you can open Linux Bash terminal and cd to nuclei-sdk folder, then run the following commands to setup build environment for Nuclei SDK, the output will be similar as this screenshot Setup Build Environment for Nuclei SDK in Linux Bash:
```
1source setup.sh
2echo $PATH
3which riscv64-unknown-elf-gcc openocd make rm
4make help
```
Setup Build Environment for Nuclei SDK in Linux Bash

Note

Only first line setup.bat or source setup.sh are required before build, run or debug application. The setup.bat and setup.sh are just used to append Nuclei RISC-V GCC Toolchain, OpenOCD and Build-Tools binary paths into environment variable PATH
line 2-4 are just used to check whether build environment is setup correctly, especially the PATH of Nuclei Tools are setup correctly, so we can use the riscv64-unknown-elf-xxx, openocd, make and rm tools
If you know how to append Nuclei RISC-V GCC Toolchain, OpenOCD and Build-Tools binary paths to PATH variable in your OS environment, you can also put the downloaded Nuclei Tools as you like, and no need to run setup.bat or source setup.sh
If you want to run in Windows PowerShell, please run . .\setup.ps1 instead of setup.bat, and setup_config.ps1 must be created as described in Get and Setup Nuclei SDK.

Here for a quick startup, this guide will take board GD32VF103V RV-STAR Kit for example to demostrate how to setup hardware, build run and debug application in Windows.

The demo application, we will take application/baremetal/helloworld for example.

First of all, please reuse previously build environment command terminal.

Run cd application/baremetal/helloworld to cd the helloworld example folder.

Hardware Preparation

Please check Board and find your board’s page, and follow Setup section to setup your hardware, mainly JTAG debugger driver setup and on-board connection setup.

Power on the GD32VF103V RV-STAR Kit board, and use USB Type-C data cable to connect the board and your PC, make sure you have setup the JTAG driver correctly, and you can see JTAG port and serial port.
Open a UART terminal tool such as TeraTerm in Windows or Minicom in Linux, and minitor the serial port of the Board, the UART baudrate is 115200 bps
If you are building example for your own SoC and Board, please pass correct SOC and BOARD make variable. eg. If you SoC is evalsoc and Board is nuclei_fpga_eval, just pass SOC=evalsoc BOARD=nuclei_fpga_eval to make instead of the one mentioned below. If your default board for this evalsoc is nuclei_fpga_eval, then you don’t need to pass BOARD=nuclei_fpga_eval.
If you don’t pass any SOC or BOARD via make, evalsoc and nuclei_fpga_eval are default SoC and Board.

If you just want to try on Nuclei Evaluation SoC, no need to pass SOC or BOARD, the default value is that, you just need to pass correct CORE, ARCH_EXT and DOWNLOAD

Build Application

We need to build application for this board GD32VF103V RV-STAR Kit using this command line:

Note

If you want to run on Nuclei Evaluation SoC, see Nuclei Eval SoC, recommend to run cpuinfo
Since below steps are taking gd32vf103 SoC based board gd32vf103v_rvstar to do demostration, and when you pass SOC=gd32vf103, the default BOARD will be gd32vf103v_rvstar, so do you don’t need to pass BOARD=gd32vf103v_rvstar
You can check default SOC/BOARD/CORE information passed by using make target info, eg. make SOC=gd32vf103 info, for more information, please check Makefile targets of make command.

# clean application if build in other application before or build for other board
make SOC=gd32vf103 BOARD=gd32vf103v_rvstar clean
# first build choice: using full command line
make SOC=gd32vf103 BOARD=gd32vf103v_rvstar all
# second build choice: using simple command line, since when SOC=gd32vf103, default BOARD is gd32vf103v_rvstar
make SOC=gd32vf103 all

Here is the sample output of this command:

# NOTICE: You can check this configuration whether it matched your desired configuration
Current Configuration: RISCV_ARCH=rv32imac RISCV_ABI=ilp32 SOC=gd32vf103 BOARD=gd32vf103v_rvstar CORE=n205 DOWNLOAD=flashxip
"Assembling : " ../../../SoC/gd32vf103/Common/Source/GCC/intexc_gd32vf103.S
"Assembling : " ../../../SoC/gd32vf103/Common/Source/GCC/startup_gd32vf103.S
"Compiling  : " ../../../SoC/gd32vf103/Board/gd32vf103v_rvstar/Source/gd32vf103v_rvstar.c
"Compiling  : " ../../../SoC/gd32vf103/Common/Source/Drivers/gd32vf103_adc.c
"Compiling  : " ../../../SoC/gd32vf103/Common/Source/Drivers/gd32vf103_bkp.c
"Compiling  : " ../../../SoC/gd32vf103/Common/Source/Drivers/gd32vf103_can.c
"Compiling  : " ../../../SoC/gd32vf103/Common/Source/Drivers/gd32vf103_crc.c
"Compiling  : " ../../../SoC/gd32vf103/Common/Source/Drivers/gd32vf103_dac.c
"Compiling  : " ../../../SoC/gd32vf103/Common/Source/Drivers/gd32vf103_dbg.c
"Compiling  : " ../../../SoC/gd32vf103/Common/Source/Drivers/gd32vf103_dma.c
"Compiling  : " ../../../SoC/gd32vf103/Common/Source/Drivers/gd32vf103_exmc.c
"Compiling  : " ../../../SoC/gd32vf103/Common/Source/Drivers/gd32vf103_exti.c
"Compiling  : " ../../../SoC/gd32vf103/Common/Source/Drivers/gd32vf103_fmc.c
"Compiling  : " ../../../SoC/gd32vf103/Common/Source/Drivers/gd32vf103_fwdgt.c
"Compiling  : " ../../../SoC/gd32vf103/Common/Source/Drivers/gd32vf103_gpio.c
"Compiling  : " ../../../SoC/gd32vf103/Common/Source/Drivers/gd32vf103_i2c.c
"Compiling  : " ../../../SoC/gd32vf103/Common/Source/Drivers/gd32vf103_pmu.c
"Compiling  : " ../../../SoC/gd32vf103/Common/Source/Drivers/gd32vf103_rcu.c
"Compiling  : " ../../../SoC/gd32vf103/Common/Source/Drivers/gd32vf103_rtc.c
"Compiling  : " ../../../SoC/gd32vf103/Common/Source/Drivers/gd32vf103_spi.c
"Compiling  : " ../../../SoC/gd32vf103/Common/Source/Drivers/gd32vf103_timer.c
"Compiling  : " ../../../SoC/gd32vf103/Common/Source/Drivers/gd32vf103_usart.c
"Compiling  : " ../../../SoC/gd32vf103/Common/Source/Drivers/gd32vf103_wwdgt.c
"Compiling  : " ../../../SoC/gd32vf103/Common/Source/Stubs/close.c
"Compiling  : " ../../../SoC/gd32vf103/Common/Source/Stubs/fstat.c
"Compiling  : " ../../../SoC/gd32vf103/Common/Source/Stubs/gettimeofday.c
"Compiling  : " ../../../SoC/gd32vf103/Common/Source/Stubs/isatty.c
"Compiling  : " ../../../SoC/gd32vf103/Common/Source/Stubs/lseek.c
"Compiling  : " ../../../SoC/gd32vf103/Common/Source/Stubs/read.c
"Compiling  : " ../../../SoC/gd32vf103/Common/Source/Stubs/sbrk.c
"Compiling  : " ../../../SoC/gd32vf103/Common/Source/Stubs/write.c
"Compiling  : " ../../../SoC/gd32vf103/Common/Source/gd32vf103_soc.c
"Compiling  : " ../../../SoC/gd32vf103/Common/Source/system_gd32vf103.c
"Compiling  : " hello_world.c
"Linking    : " hello_world.elf
text    data     bss     dec     hex filename
13022     112    2290   15424    3c40 hello_world.elf

As you can see, that when the application is built successfully, the elf will be generated and will also print the size information of the hello_world.elf.

Note

In order to make sure that there is no application build before, you can run make SOC=gd32vf103 BOARD=gd32vf103v_rvstar clean to clean previously built objects and build dependency files.
About the make variable or option(SOC, BOARD) passed to make command, please refer to Build System based on Makefile.

Run Application

If the application is built successfully for this board GD32VF103V RV-STAR Kit, then you can run it using this command line:

make SOC=gd32vf103 BOARD=gd32vf103v_rvstar upload

Here is the sample output of this command:

"Download and run hello_world.elf"
riscv64-unknown-elf-gdb hello_world.elf -ex "set remotetimeout 240" \
        -ex "target remote | openocd -c \"gdb_port pipe; log_output openocd.log\" -f ../../../SoC/gd32vf103/Board/gd32vf103v_rvstar/openocd_gd32vf103.cfg" \
        --batch -ex "monitor halt" -ex "monitor halt" -ex "monitor flash protect 0 0 last off" -ex "load" -ex "monitor resume" -ex "monitor shutdown" -ex "quit"
D:\Software\Nuclei\gcc\bin\riscv64-unknown-elf-gdb.exe: warning: Couldn't determine a path for the index cache directory.
Nuclei OpenOCD, 64-bit Open On-Chip Debugger 0.10.0+dev-00014-g0eae03214 (2019-12-12-07:43)
Licensed under GNU GPL v2
For bug reports, read
        http://openocd.org/doc/doxygen/bugs.html
_start0800 () at ../../../SoC/gd32vf103/Common/Source/GCC/startup_gd32vf103.S:359
359         j 1b
cleared protection for sectors 0 through 127 on flash bank 0

Loading section .init, size 0x266 lma 0x8000000
Loading section .text, size 0x2e9c lma 0x8000280
Loading section .rodata, size 0x1f0 lma 0x8003120
Loading section .data, size 0x70 lma 0x8003310
Start address 0x800015c, load size 13154
Transfer rate: 7 KB/sec, 3288 bytes/write.
shutdown command invoked
A debugging session is active.

        Inferior 1 [Remote target] will be detached.

Quit anyway? (y or n) [answered Y; input not from terminal]
[Inferior 1 (Remote target) detached]

As you can see the application is uploaded successfully using openocd and gdb, then you can check the output in your UART terminal, see Nuclei SDK Hello World Application UART Output.

Nuclei SDK Hello World Application UART Output

Debug Application

If the application is built successfully for this board GD32VF103V RV-STAR Kit, then you can debug it using this command line:

make SOC=gd32vf103 BOARD=gd32vf103v_rvstar debug

The program is not loaded automatically when you enter to debug state, just in case you want to debug the program running on the board.

"Download and debug hello_world.elf"
riscv64-unknown-elf-gdb hello_world.elf -ex "set remotetimeout 240" \
        -ex "target remote | openocd -c \"gdb_port pipe; log_output openocd.log\" -f ../../../SoC/gd32vf103/Board/gd32vf103v_rvstar/openocd_gd32vf103.cfg"
D:\Software\Nuclei\gcc\bin\riscv64-unknown-elf-gdb.exe: warning: Couldn't determine a path for the index cache directory.
GNU gdb (GDB) 8.3.0.20190516-git
Copyright (C) 2019 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.
Type "show copying" and "show warranty" for details.
This GDB was configured as "--host=i686-w64-mingw32 --target=riscv64-unknown-elf".
Type "show configuration" for configuration details.
For bug reporting instructions, please see:
<http://www.gnu.org/software/gdb/bugs/>.
Find the GDB manual and other documentation resources online at:
    <http://www.gnu.org/software/gdb/documentation/>.
--Type <RET> for more, q to quit, c to continue without paging--

For help, type "help".
Type "apropos word" to search for commands related to "word"...
Reading symbols from hello_world.elf...
Remote debugging using | openocd -c \"gdb_port pipe; log_output openocd.log\" -f ../../../SoC/gd32vf103/Board/gd32vf103v_rvstar/openocd_gd32vf103.cfg
Nuclei OpenOCD, 64-bit Open On-Chip Debugger 0.10.0+dev-00014-g0eae03214 (2019-12-12-07:43)
Licensed under GNU GPL v2
For bug reports, read
        http://openocd.org/doc/doxygen/bugs.html
_start0800 () at ../../../SoC/gd32vf103/Common/Source/GCC/startup_gd32vf103.S:359
359         j 1b

If you want to load the built application, you can type load to load the application.

(gdb) load
Loading section .init, size 0x266 lma 0x8000000
Loading section .text, size 0x2e9c lma 0x8000280
Loading section .rodata, size 0x1f0 lma 0x8003120
Loading section .data, size 0x70 lma 0x8003310
Start address 0x800015c, load size 13154
Transfer rate: 7 KB/sec, 3288 bytes/write.

If you want to set a breakpoint at main, then you can type b main to set a breakpoint.
```
(gdb) b main
Breakpoint 1 at 0x8001b04: file hello_world.c, line 85.
```
If you want to set more breakpoints, you can do as you like.

Then you can type c, then the program will stop at main

(gdb) c
Continuing.
Note: automatically using hardware breakpoints for read-only addresses.

Breakpoint 1, main () at hello_world.c:85
85          srand(__get_rv_cycle()  | __get_rv_instret() | __RV_CSR_READ(CSR_MCYCLE));

Then you can step it using n (short of next) or s (short of step)

(gdb) n
86          uint32_t rval = rand();
(gdb) n
87          rv_csr_t misa = __RV_CSR_READ(CSR_MISA);
(gdb) s
89          printf("MISA: 0x%lx\r\n", misa);
(gdb) n
90          print_misa();
(gdb) n
92          printf("Hello World!\r\n");
(gdb) n
93          printf("Hello World!\r\n");

If you want to quit debugging, then you can press CTRL - c, and type q to quit debugging.

(gdb) Quit
(gdb) q
A debugging session is active.

        Inferior 1 [Remote target] will be detached.

Quit anyway? (y or n) y
Detaching from program: D:\workspace\Sourcecode\nuclei-sdk\application\baremetal\helloworld\hello_world.elf, Remote target
Ending remote debugging.
[Inferior 1 (Remote target) detached]

Note

More about how to debug using gdb, you can refer to the GDB User Manual.
If you want to debug using Nuclei Studio, you can open Nuclei Studio, and create a debug configuration, and choose the application elf, and download and debug in IDE.

Create helloworld Application

If you want to create your own helloworld application, it is also very easy.

There are several ways to achieve it, see as below:

Method 1: You can find a most similar sample application folder and copy it, such as application/baremetal/helloworld, you can copy and rename it as application/baremetal/hello
- Open the Makefile in application/baremetal/hello
  1. Change TARGET = hello_world to TARGET = hello
- Open the hello_world.c in application/baremetal/hello, and replace the content using code below:
  1// See LICENSE for license details. 2#include <stdio.h> 3#include <time.h> 4#include <stdlib.h> 5#include "nuclei_sdk_soc.h" 6 7int main(void) 8{ 9 printf("Hello World from Nuclei RISC-V Processor!\r\n"); 10 return 0; 11}
- Save all the changes, and then you can follow the steps described in Build, Run and Debug Sample Application to run or debug this new application.

Method 2: You can also do it from scratch, with just create simple Makefile and main.c

Create new folder named hello in application/baremetal
Create two files named Makefile and main.c

Open Makefile and edit the content as below:

TARGET = hello

NUCLEI_SDK_ROOT = ../../..

SRCDIRS = .

INCDIRS = .

include $(NUCLEI_SDK_ROOT)/Build/Makefile.base

Open main.c and edit the content as below:

// See LICENSE for license details.
#include <stdio.h>
#include <time.h>
#include <stdlib.h>
#include "nuclei_sdk_soc.h"

int main(void)
{
    printf("Hello World from Nuclei RISC-V Processor!\r\n");
    return 0;
}

Save all the changes, and then you can follow the steps described in Build, Run and Debug Sample Application to run or debug this new application.

Note

If your are looking for how to run for other boards, please ref to Board.
Please refer to Application Development and Build System based on Makefile for more information.
If you want to access SoC related APIs, please use nuclei_sdk_soc.h header file.
If you want to access SoC and board related APIs, please use nuclei_sdk_hal.h header file.
For simplified application development, you can use nuclei_sdk_hal.h directly.

Advanced Usage

For more advanced usage, please follow the items as below:

Click Design and Architecture to learn about Nuclei SDK Design and Architecture, Board and SoC support documentation.
Click Developer Guide to learn about Nuclei SDK Build System and Application Development.
Click Application to learn about each application usage and expected output.

Note

If you met some issues in using this guide, please check FAQ, if still not solved, please Submit your issue.
If you are trying to develop Nuclei SDK application in IDE, now you have three choices:
1. Recommended: Since Nuclei Studio 2020.08, Nuclei SDK will be deeply integrated with Nuclei Studio IDE, you can easily create a Nuclei SDK Project in Nuclei Studio through IDE Project Wizard, and easily configure selected Nuclei SDK project using SDK Configuration Tool, for more details, please click Nuclei Tools to download Nuclei Studio IDE, and refer to the Nuclei_Studio_User_Guide.pdf for how to use it.
2. Now Terapines ZCC Lite is deeply integrated in Nuclei Studio >= 2024.06, so you just need to follow Get and Setup Nuclei SDK to setup PATH for Terapines ZCC, and in Nuclei SDK, you can just pass TOOCHAIN=terapines during make to take a try with Terapines ZCC. From 0.7.0 release, you can create project in Nuclei Studio >= 2024.06 using Terapines ZCC.
3. You can take a try using IAR workbench, we provided prebuilt projects directly in Nuclei SDK, just check the ideprojects/iar/README.md to learn about it.
4. You can take a try using Segger embedded studio, we provided prebuilt projects using Nuclei SDK release version, click Segger embedded studio projects for Nuclei SDK to learn about it
5. You can also take a try with the Cross-platform PlatformIO IDE, we provided our Nuclei platform and Nuclei SDK release version in PlatformIO, click Platform Nuclei in PlatformIO to learn more about it, or you can visit Light on onboard LED of RVSTAR board using PlatformIO(Chinese) to play with PlatformIO for Nuclei.
6. You can also use source code in Nuclei SDK as base, and easily integrate with other IDE tools, such as ZStudio IDE, Compiler-IDE and others.