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A real 68000-class computer you solder yourself.

Open-hardware kits shipped worldwide. Solder the board, boot it over serial, and program it right down to the metal. Then grow it one expansion card at a time.

  • MC68010 @ 10 MHz
  • 1 MB RAM
  • UART console
  • Boots from SD card
rosco_m68k board assembled by Solder Demon

Pick your starting point

Every rosco_m68k system begins with the main board kit. The busboard and the RAM expansion are the first two cards you add to it.

  1. ROSCO M68K — DIY Retro Computer Kit01 · Start here
    In Stock
    Build video · 4:43

    ROSCO M68K — DIY Retro Computer Kit

    ROSCO M68K is a DIY kit for building an educational retro computer based on the Motorola 68010 CPU. All components use through-hole technology, making the kit accessible even for those who are new to soldering. It is a solid platform for understanding core computer concepts such as memory, buses, clocking, firmware, bootloaders, and low-level programming.

    View
  2. rosco_m68k Bus Board02 · Then add
    In Stock
    Build video · 2:41

    rosco_m68k Bus Board

    Expansion board for rosco_m68k — connects the main board to peripheral modules via a standard bus. Allows you to attach additional expansion cards: memory, video, sound, and other modules compatible with the rosco_m68k ecosystem.

    View
  3. rosco_m68k RAM Expansion Board03 · Then add
    In Stock
    Build video · 5:33

    rosco_m68k RAM Expansion Board

    4MB SRAM expansion board for the rosco_m68k retro computer. Expands your system memory with eight AS6C4008 512K×8 SRAM chips, providing the full 4 megabytes of fast static RAM addressable over the expansion bus. Perfect for running larger programs, heavier workloads, and memory-hungry applications on your 68k machine.

    View

kit + busboard + RAMtogether make the full base system: CPU, backplane, and 4 MB of extra memory.

All products
Also in the storeLilka — DIY Assembly Ki

rosco_m68k in action

A terminal recording of life and adventure games running on a real board, the full build on video, plus live boot logs and on-board memory tests.

rosco_m68k terminal recording with life and adventure games
0:00 / 0:00

Assembly in under five minutes

The full build of the rosco_m68k kit, from the first resistor to the first boot.

Terminal window showing UART output from the board

UART output

Boot and diagnostic messages streaming over the serial port.

Screenshot of the memory test program

ROM / RAM test

Checks ROM and RAM integrity on a live board.

A busboard at the core, cards around it

The busboard is the backplane: the main CPU board sits on it, and every expansion card plugs into the same bus. Grow the system one card at a time.

rosco_m68k and rosco_6502 were not designed by us. They are open projects we forked to build new cards, write software, and keep them evolving.

Original rosco_m68kOriginal rosco_6502

Main board

68010 or 6502

RAM Expansion

GPIO

Audio

Video

Busboard · shared system bus
Busboard

Busboard

The backplane the main board plugs into, with slots for every expansion card.

  • rosco_m68kDone
  • rosco_6502Planned
RAM Expansion

RAM Expansion

Extra memory on the bus for bigger programs and operating systems.

  • rosco_m68kDone
  • rosco_6502Planned
GPIO

GPIO

General-purpose inputs and outputs for talking to the outside world.

then: keyboard and mouse

  • rosco_m68kIn progress
  • rosco_6502Planned

Get one email when this card ships

Audio

Audio

A sound card so the machine can finally make some noise.

  • rosco_m68kIn progress
  • rosco_6502Planned

Get one email when this card ships

Photo coming soon

Video

Video output that turns the serial-console computer into a full workstation.

  • rosco_m68kPlanned
  • rosco_6502Planned

Get one email when this card ships

Computers you can understand completely

Modern systems hide everything behind layers of abstraction. On rosco there are few layers, and every one of them is open.

Typical PC

  1. Your code
  2. Framework
  3. Runtime
  4. Operating system
  5. Drivers
  6. UEFI firmware
  7. SoC — a black box

rosco

  1. Your code
  2. rosco firmware (open)
  3. 68010 / 65C02
  4. Bus: RAM · ROM · UART

Between your code and the silicon there are only a couple of steps, and you can read the source of each one.

Motorola 68010MOS 6502

Real CPUs

Genuine 68010 and 6502-family chips. No emulation layer in between.

Every signal is visible

Address, data, and strobes are on the bus. Hook up a logic analyzer and watch the CPU work.

    lea     buf, a0    moveq   #15, d0.fill:    move.b  #$AA, (a0)+    dbra    d0, .fill

Code talks to hardware

A few lines of assembly and you are filling memory directly, with no OS in the way.

Repairable by design

DIP chips and modular boards. Pull a part, check it, replace it.

Made forHardware-curious makersDevelopers and engineersStudents and self-learners
~/hello

  1. # create a project for your board

    $ rosco init hello --board rosco_m68k

  2. # compile with the right toolchain

    $ rosco build

  3. # upload over UART and watch the output

    $ rosco run --hardware

rosco CLI

One workflow for rosco_m68k and rosco_6502: create a project, build it, upload it over UART, and see the output. Works with the real board or the emulator.

  • Same commands for 68k and 65C02 projects
  • Runs in the emulator when the board is not at hand
  • Programs and your own firmware
  • Linux and Windows, x64 and ARM64
rosco-cli on GitHub

Where Solder Demon is heading

What is shipped, what is on the bench, and what comes after.

  1. 01 · Done

    Shipped

    • rosco_m68k main board

      The 68010 CPU board from the original rosco project. Ready units and DIY kits in the store.

    • rosco_m68k Busboard

      Backplane with slots for the main board and expansion cards.

    • rosco_m68k RAM Expansion

      Extra memory on the bus.

  2. 02 · In progress

    On the bench

    • rosco_m68k Audio

      Sound card for rosco_m68k.

    • rosco_m68k GPIO

      General-purpose I/O card.

  3. 03 · Next

    Up next

    • Keyboard and mouse

      Input devices connected through the GPIO card.

    • rosco_m68k Video

      Video card that completes the base set for rosco_m68k.

  4. 04 · Planned

    Later

    • rosco_6502 base set

      Busboard, RAM, GPIO, audio, and video for rosco_6502.

    • Documentation and guides

      Assembly instructions, videos, and practical examples for every card.

Get one email when the next card ships

Audio and GPIO are on the bench, video comes next. Leave your email and we will tell you the day they land in the store. Nothing else.

One email when it ships. No newsletter, and we never share the address.

Prefer chat? Progress lands first in Telegram and Discord. All channels