Maix Bit

Tags: experimental arch:risc-v chip:k210 vendor:sipeed

The Maix Bit is a RISC-V AI IoT development board.

Features

K210 RISC-V AI Chip
Dual-core
Independent FPU
64-bit
8MB on-chip SRAM
Double precision FPU with multiplication, division and square root

Warning

There is currently no support for the FPU, or RISC-V User mode. Peripherals such as GPIO, SPI and I2C are also currently unsupported.

Todo

If you are interested in using this board, please consider contributing implementations for the above missing features.

Installation

Download and install toolchain and openocd-k210

$ curl https://static.dev.sifive.com/dev-tools/riscv64-unknown-elf-gcc-8.3.0-2019.08.0-x86_64-linux-ubuntu14.tar.gz
$ export PATH=$PATH:/$TOOL_CHAIN_PATH/bin

Build openocd-k210

$ git clone https://github.com/kendryte/openocd-kendryte
$ cd openocd-kendryte
$ ./bootstrap & ./configure & make

Flashing

Download and run NuttX from SRAM (not SPI-Flash):

$ picocom -b 115200 /dev/ttyUSB0
$ sudo ./src/openocd -s ./tcl -f ./tcl/kendryte.cfg -m 0
$ riscv64-unknown-elf-gdb ./nuttx
(gdb) target extended-remote :3333
(gdb) load nuttx
(gdb) c

Write nuttx.bin to SPI-Flash:

$ pip3 install kflash
$ kflash -p /dev/ttyUSB0 -b 1500000 ./nuttx/nuttx.bin

Note

The kflash_gui is not recommended because it’s unstable.

Configurations

Configurations can be selected using the following configure tool command:

$ ./tools/configure.sh maix-bit:<config>

Where <config> can be replaced by the name of any configuration listed below.

nsh

A simple configuration with NSH running.