bsp/nuclei: Add more information in hbird_eval doc

Signed-off-by: Huaqi Fang <578567190@qq.com>

bsp/nuclei/hbird_eval/README.md

@@ -70,7 +70,12 @@ export PATH=~/Software/Nuclei/gcc/bin:~/Software/Nuclei/openocd/bin:$PATH
 1. 运行 ``pkgs --update``来下载最新的依赖的**Nuclei SDK**开发包
 2. **可选**: 运行 ``menuconfig``来进行内核配置
 3. 运行 ``scons -c``清理之前的编译结果
-4. 运行 ``scons``来进行代码的编译
+4. 根据你当前评估的Nuclei RISC-V内核情况，修改 ``rtconfig.py``中的``NUCLEI_SDK_CORE``和``NUCLEI_SDK_DOWNLOAD``参数。
+   - ``NUCLEI_SDK_CORE``可选的参数为[Supported Nuclei Cores](https://doc.nucleisys.com/nuclei_sdk/develop/buildsystem.html#core)
+   - ``NUCLEI_SDK_DOWNLOAD``可选的参数为``ilm``,``flash``或者``flashxip``, 关于该选项的说明参见[Supported Download Modes](https://doc.nucleisys.com/nuclei_sdk/develop/buildsystem.html#download)
+   - 假设你手头拿到的Nuclei评估处理器内核为N307(rv32imafc), 想程序运行模式为``flash``,
+     则修改``NUCLEI_SDK_CORE``为``n307``, ``NUCLEI_SDK_DOWNLOAD``为``flash``.
+5. 修改完对应的``rtconfig.py``参数配置并保存后，运行 ``scons``来进行代码的编译
 
 ### 下载程序
 

bsp/nuclei/hbird_eval/rtconfig.py

@@ -22,7 +22,9 @@ BUILD = 'debug'
 NUCLEI_SDK_SOC = "hbird"
 NUCLEI_SDK_BOARD = "hbird_eval"
 # Configurable options below
+# DOWNLOAD: https://doc.nucleisys.com/nuclei_sdk/develop/buildsystem.html#download
 NUCLEI_SDK_DOWNLOAD = "ilm"
+# CORE: See https://doc.nucleisys.com/nuclei_sdk/develop/buildsystem.html#core
 NUCLEI_SDK_CORE = "nx600"
 
 if PLATFORM == 'gcc':