The DECStation 2040 Puts What Was Once the Fastest UNIX System in the World in Your Wallet
What was once a powerful workstation on your desk can now be a curiosity in your pocket — thanks to the Raspberry Pi RP2040.
Pseudonymous engineer "rscott2049," hereafter simply "Scott," wants to put a Digital DECstation MIPS-based workstation in your wallet — thanks to a Raspberry Pi RP2040-powered emulator the size of a business card.
"This is a custom RP2040 based business card that runs Ultrix/DECwindows," Scott explains of the device, dubbed the DECstation 2040. Inspired by the DECstation line-up of the late 1980s, launched by Digital with the claim of being the world's fastest UNIX workstation, the DECstation 2040 swaps out the original device's MIPS processor for an Arm-based Raspberry Pi RP2040 — a microcontroller, but one delivering enough of a boost in performance to emulate its ancestor perfectly.
Building atop Dmitry Grinberg's earlier LinuxCard project, which emulated a MIPS-architecture system on a Microchip ATSAMD21 microcontroller, the DECstation 2040 runs its RP2040 chip heavily overclocked to 300MHz and adds 8MB of SPI-connected flash memory and 32MB of pseudo-static RAM (PSRAM) to work around the chip's somewhat-limited 264kB of internal SRAM. This is driven from the RP2040's programmable input/output (PIO) blocks, delivering 42 and 32MB/s of write and read bandwidth respectively.
Despite its small size, fitting into the footprint of a business card, the device also includes a microSD Card socket for storage expansion, a VGA video output delivering a surprisingly high 1024×864 resolution, Ethernet connectivity, and a USB interface for a keyboard and mouse. This latter feature includes conversion to the DECWindows standard — allowing modern peripherals to control the system, which is designed to run Digital's Ultrix UNIX distribution and, optionally, the DECWindows desktop environment on top.
"This project has been a voyage of discovery," Scott concludes. "The first doc/build_log.txt entry was on 23-Mar-2023, but I'd been thinking of building a business card ever since I'd read Dmitry's LinuxCard web page. I've learned how to use the RP2040 PIO engines and the DMA subsystem to push pixels. I'm amazed at how flexible and capable the RP2040 has turned out to be. Hats off to the RP2040 designers!"
The project is documented in full on Scott's GitHub repository, with hardware design files and firmware sources released under the permissive BSD 3-Clause license; more information is available on Hackaday.io.