A New Six Dollar Linux Computer?

Alasdair Allan
3 min readNov 12, 2018

The arrival of the Espressif ESP8266 changed everything, and a sign that we’ve entered an age where computing is practically cheap enough to throw away. Yet over the last year or two we’ve seen the the price of boards drop even further, cumulating just last month with the arrival of the Air602 module from Seeed Studio — a Wi-Fi-enabled microcontroller which can be picked up Taobao for just a single dollar.

But none of these “practically free” boards run Linux. Despite attempts at revival, with the demise of NextThing Co, the cheapest way to run Linux is still the Raspberry Pi Zero, or the Zero W if you want a board with Wi-Fi.

It’d be nice if there was some competition? Which is perhaps where this new C-SKY board might come in, although you’ll have to make some compromises.

The new C-SKY board. (📷: C-SKY Linux)

This board is built around a chip you’ve probably never heard of before. It’s not an Arm, or MIPS, and while the company behind is is a member of the RISC-V consortium, this isn’t a RISC-V chip either. Instead the board is based on a NationalChip GX6605S using the C-SKY architecture intended for DVB set-top boxes, and despite the way it’s advertised on Taobao and AliExpress, this board also has nothing to do with either OrangePi or the Raspberry Pi Foundation.

Introduction to the GX6605S-based C-SKY development board. (📷: 郭任)

There is no network connectivity, no wired Ethernet or Wi-Fi is available, nor does it have storage on board. However, the 32-bit GX6605S processor runs at 574 MHz and has 64MB DDR2 RAM, and there is 4MB of SPI flash on board.

Hereditary shows through with the built-in DVB-S2/S demodulator, and support for video output via the on board HDMI connector at 1080p. Although the frame buffer is just 1280×720, so presumably there’s some upscaling going on there? The board also has 2×USB2.0 host, UART, JTAG, and GPIO ports, along with five on board “user” buttons.

Lay out of the C-SKY development board. (📷: C-SKY Linux)

Until recently, the Linux kernel has been supported by the manufacturer, however the C-SKY architecture has been approved for the mainline Linux kernel, so ongoing support for the architecture is now more assured.

“I think this may well be the last new CPU architecture we ever add to the kernel. Both NDS32 and C-SKY are made by companies that also work on RISC-V, and generally speaking RISC-V seems to be killing off any of the minor licensable instruction set projects, just like Arm has mostly killed off the custom vendor-specific instruction sets already.”Arnd Bergmann, Linux Kernel Developer

This is an odd board, and much like the Air602 I talked about last month, most of the documentation is still in Chinese. A month after release that’s starting to change for the Air602 at least, as there isn’t much English documentation available for this C-SKY-based board.

Despite the overall oddness, what makes it worthwhile is the price. Because this new development board is available for ¥ 39.00 (that’s under $6) on Taobao. Although if you’re not proficient in sourcing parts on Taobao, it gets rather more expensive as it’s marked up at a somewhat inflated $19.50 with free shipping on AliExpress. Which is somewhat less attractive, but if the history of the ESP8266 and other low-cost boards is anything to go by, that price point is likely to drop pretty quickly towards the Taobao price if the board proves popular.

Nonetheless, if you’re interested in poking around with odd hardware, and have access to Taobao, you might want to invest six dollars to play around with some new hardware. I’ll probably pick up a few myself.