DevTerm R-01
The first portable, retail, affordable RISC-V computer
So, for those who are not aware, ClockworkPi has been making a retro-styled mobile computer. It will remind older readers of the TRS-80 100 and other similar machines. It even has an expansion port to which a small thermal printer attaches. The DevTerm has now gotten a RISC-V treatment (using the Allwinner D1).
All of the DevTerm machines come in the same stylish housing, and have roughly the same features. The place the models differ is in the compute module. For anyone familiar with the Raspberry Pi line of computers, the modules are similar to the RaspberryPi CM3. Indeed, you can purchase a DevTerm that utilizes the Rpi CM3. The R-01 compute module is what makes this most recent DevTerm so different.
It's a 64bit, single core, 1ghz CPU. There's no GPU, so the graphics are software rendered. The R01 computer module packs 1GB of RAM. This may seem... low spec, because it is. The thing to remember is that there's not much screen to render, and on a screen so small (1280x480, or two VGA displays next to one another, 6.8 inches, IPS), it is highly unlikely that anyone is going to be doing production work. Writing? Sure. Light programming? Sure. Some retro gaming? Absolutely. The DevTerm features a built in game controller just for that. It's important to remember that the compute module can be changed out as well. If you wanted more power, it is available with, for example, the A06. There is also a micro-hdmi port and three USB-A ports (2.0). As such, it is also possible to use an external display, and external keyboard/mouse if truly desired. Power is provided via two 18650 lithium batteries (user supplied) or via USB-C (which is also for charging). Storage is on TF card, for which there's a slot on the front of the machine next to the power switch. The keyboard is a bit cramped, it will remind people of the Asus eeepc keyboards and other similar netbooks, but this one has a mini-track ball on it too!
For the most part, the DevTerm is an underpowered computer in a small and completely non-ergonomic form factor. Yet, it ships as a kit, is completely repairable, upgradeable, and hackable. This is also a machine that you can purchase right now and has a RISC-V CPU in it. If you find that the RISC-V isn't up to snuff, you can always get a different compute module. If you made it this far in this article, however, I am thinking that the RISC-V is one of the selling points.
For my part, no matter what the machine may lack, I totally ordered one as soon as I found out about it. The main addition that I would make is to add an external serial port, and possible an ethernet port... but having USB, I suppose I can overcome those limitations. Perhaps the biggest issue is that the machine is expected to take 60 days to get here...
The datasheet on the Allwinner D1 that powers the devterm R-01 says that there are all these features:
Allwinner D1 SOC facts in brief:
CPU Alibaba XuanTie C906 64bit RISC-V core with 32 KB I-cache + 32 KB D-cache
DSP HiFi4 DSP 600MH with 32 KB I-cache + 32 KB D-cache, 64 KB I-ram + 64 KB D-ram
Memory I/F Up to 2GB DDR2/DDR3
Storage I/F SD3.0, eMMC 5.0, SPI Nor/Nand Flash
Decode H.265 up to 1080p@60fps, or 4K@30fps
Decode H.264 up to 1080p@60fps, or 4K@24fps
Decode MPEG-1/2/4, JPEG, VC1 up to 1080p@60fps
Encode JPEG/MJPEG up to 1080p@60fps
Supports input picture scaler up/down
RGB LCD video output interface up to 1920 x 1080@60fps
Dual link LVDS output interface up to 1920 x 1080@60fps
4-lane MIPI DSI output interface up to 1920 x 1080@60fps
HDMI V1.4 output interface up to 4K@30fps
CVBS OUT interface, supporting NTSC and PAL format
8-bit parallel CSI input interface
CVBS IN interface supporting NTSC and PAL format
Audio 2x DAC’s and 3x ADC’s
Analog audio interfaces MICIN1P/N, MICIN2P/N, MICIN3P/N, FMINL/R, LINEINL/R, LINEOUTLP/N, LINEOUTRP/N, HPOUTL/R
Digital audio interfaces I2S/PCM, DMIC, OWA IN/OUT
Networking 10/100/1000M EMAC with RMII and RGMII interfaces
USB USB2.0 OTG, USB2.0 Host
SDIO 3.0, SPI x 2, UART x 6, TWI x 4
PWM (8-ch), GPADC (2-ch), LRADC (1-ch), TPADC (4-ch), IR TX&RX
Package LFBGA BGA13 13/0.35/0.65mm 337 PINS
Manufacturing process 22nm