1. Download and install toolchain

$ curl https://static.dev.sifive.com/dev-tools/riscv64-unknown-elf-gcc-8.3.0-2019.08.0-x86\_64-linux-ubuntu14.tar.gz

2. Download and install J-Link Software Documentation Pack

https://www.segger.com/downloads/jlink/

$ sudo apt install JLink_Linux_V656b_x86_64.deb

3. Configure and build NuttX

$ mkdir ./nuttx; cd ./nuttx $ git clone https://github.com/apache/nuttx.git nuttx $ git clone https://github.com/apache/nuttx-apps.git apps $ cd nuttx $ make distclean $ ./tools/configure.sh hifive1-revb:nsh $ make V=1

4. Flash the nuttx with J-Link and run

$ picocom -b 115200 /dev/ttyACM0

$ /opt/SEGGER/JLink_V656b/JLinkGDBServer -device FE310

$ riscv64-unknown-elf-gdb ./nuttx (gdb) target extended-remote:2331 (gdb) load nuttx (gdb) c

5. TODO

Support GPIO/SPI/I2C/RTC/WDT/PWM Support RISC-V User mode