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There’s been some exciting news about RISC-V microcontrollers recently with Gigadevice announcing GD32V, one of the first RISC-V general-purpose microcontrollers, which outperforms its Arm Cortex-M3 equivalent in terms of performance and power consumption.

The company also announced some development boards, but they are not quite that easy to purchase being listed on Tmall website in China. The good news is that Sipeed has introduced Longan Nano development board powered by GD32VF103CBT6 microcontroller, and it’s up for sale on Seeed Studio for $4.9.

Longan Nano, which Sipeed also calls “Red Bill” in reference to STM32 Bluepill board, can run RT-Thread & LiteOS operating systems, and software development can be performed with tools such as the PlatformIO IDE, the Arduino IDE (soon), GCC and OpenOCD.

There are three ways to load firmware to the board: USB DFU download, UART ISP download, JTAG download. The first method just requires a USB-C cable, and the others a USB-UART debug board and a JTAG-enabled debugger (e.g. J-Link) respectively.You can find GD32V development platform for PlatformIO on Github, download software & hardware documentation and tools from an HTTP folder, and get support via Telegram. There’s also a documentation website, but at the time of writing, it’s pretty much empty.

Jean-Luc started CNX Software in 2010 as a part-time endeavor, before quitting his job as a software engineering manager, and starting to write daily news, and reviews full time later in 2011.

Wow! USB-C! Does it work at full USB3.x speed though? That would be super-cool! Somebody, please make Arduino bootloader and libs! (the article promises it “soon”, but how soon is that?) As relationships between US and China are getting more complicated, we (hobbyists) might soon have to replace ARM with RISK-V in our toolbox. Let’s get prepared.

Of course he does not. The GD32VF103s (in the $ 1 range) are microcontrollers. The provided USB2.0 – FS is more than enough to download programs.

Taking Jerry’s defence for once, he mentioned megabytes and the number in his joke was correct in that USB3 superspeed is indeed 5 Gbps. However here it’s clear that we must not expect more than 12 Mbps.

FYI USB is usually implemented with a DMA engine i.e. the CPU doesn’t actually need to be able to write data at the same rate as it gets transmitted.

4 bytes/cycle maybe if the DMA engine is really good on a little 32 bit micro, but 5.8 bytes/cycle?