Longan Nano: $5 RISC-V Micro controller board
The list of RISC-V ISA based boards has been growing rapidly and is now joined by the low cost Longan Nano from Sipeed. This board is good for hobbyists and students who want to use a low cost RISC-V based microcontroller (MCU)for their projects.
Longan Nano MCU
The Longan Nano board uses a GD32VF103CBT6 MCU from Gigadevice. The MCU uses a 32-bit RISC-V based Bumblebee Core from Nuclei System Technology. According to Gigadevice the GDV32 MCU performance is comparable to a Gigadevice Cortex-M3 MCU while consuming 50% less power. The key specifications for the MCU used on the board are:
- Processor core frequency — 108 MHz
- On-chip Flash memory — 128 KB
- On-chip SRAM — 32 KB
- Peripherals — 12-bit ADC, 12-bit DAC, 16-bit timers etc
- Interfaces — SPI, I2C etc
- Supply — 2.6V — 3.6V
For detailed specs refer to the GD32VF103 datasheet.
Longan Nano Board
In my opinion the best part about the Longan Nano board is that for less than $5 you get a board with a 0.96inch 160x80 IPS RGB LCD which will allow people to make some cool demos. Other than the LCD you also get a transparent acrylic case. The board also comes with a Type-C USB interface for programming and power. It also supports the standard JTAG interface, which can be debugged using any JTAG-enabled debugger such as J-Link.
Getting Started
To program the board Sipeed had adapted the PlatformIO Integrated development environment (IDE) to work with the GDV32 MCU. The IDE works on windows, mac and linux based platforms. The IDE can be configured to work with this board by following the instruction provided on Sipeed github page. Sipeed has also provided an example on how to blink an LED using the IDE. You can also use RTOS like the Huawei LiteOS or RT-thread. By the time board ships hopefully the document ion will be better and there will be more examples.
This board is a good option for anyone looking to get started with RISC-V microcontrollers as other RISC-V boards cost much more. The board is available for pre-order from Seeed Studio.
https://www.seeedstudio.com/Grove-AI-HAT-for-Edge-Computing-p-4026.html
