Linchpin

This repo contains a mixed C# and C codebase for working with the Cornerstone virtual machine. It includes:

• C# tools for assembling, inspecting, running, disassembling, and repackaging Cornerstone images.
• Native runtimes for Commodore 128, Atari ST, Amiga, and POSIX hosts.
• Bundled sample data.

Repository layout

• Cornerstone/ - install Cornerstone here before running the test suite.
• data/ - shared instruction grammar used by the assembler and C# interpreter.
• DB/ - database files used for testing.
• src/Chisel/ - C# assembler that turns .cas source into .obj and .mme images.
• src/Linchpin/ - C# interpreter and disassembler for Cornerstone images.
• src/LP128Pack/ - C# bundler that packages .mme + .obj into a .csb bundle for the C128 runtime.
• src/Linchpin128/ - C runtime for POSIX and Commodore 128 targets.
• src/LinchpinST/ - C runtime for POSIX, Atari ST, and Amiga targets.
• test/Linchpin.ToolTests/ - MSTest suite for the C# tools.
• test/Linchpin.TestCaseTool/ - helper for creating interpreter-based test cases.

Projects

C# projects

src/Chisel

Assembler for the Cornerstone VM. It reads .cas source and produces .obj and .mme output files.

Example source files are under src/Chisel/examples/.

src/Linchpin

Interpreter and disassembler for Cornerstone images. Main commands:

• run - execute the VM.
• inspect - print image metadata and an entrypoint preview.
• disassemble - emit reconstructed assembler source.

src/LP128Pack

Packs a Cornerstone .mme and .obj pair into a .csb bundle for the Linchpin128 runtime.

Native C projects

src/Linchpin128

Native runtime for the Cornerstone VM.

• make posix builds a POSIX-hosted executable.
• make c128 builds a Commodore 128 program with llvm-mos.
• make c128-d64, make c128-d71, and make c128-d81 also create disk images.

The C128 disk-image targets use VICE c1541.exe from WSL and can optionally embed a .csb bundle.

src/LinchpinST

Native runtime for multiple classic targets.

• make posix builds a POSIX-hosted executable.
• make atari / make atari-tos build Atari binaries.
• make atari-disk builds an Atari ST disk image.
• make amiga, make amiga-adf, and make amiga-hdf build Amiga binaries and disk images.
• make amiga-fpu and related targets build the 68040/FPU Amiga variant.

src/LinchpinST/LinchpinST.proj is an MSBuild wrapper that calls wsl make, but the actual native compilation still happens inside WSL.

Prerequisites

Windows host

• Visual Studio or Build Tools with MSBuild support.
• .NET SDK 10.0 for the C# projects.
• WSL for all native C builds.

WSL tools

At minimum:

• make
• gcc for POSIX builds
• python3 for the Commodore 128 launcher generator

Additional target-specific tools:

• llvm-mos for src/Linchpin128 Commodore 128 builds
• VICE c1541.exe reachable from WSL for Commodore disk-image targets
• m68k-atari-mintelf-gcc or m68k-atari-mint-gcc for Atari builds
• dosfstools and mtools for Atari disk-image generation
• m68k-amigaos-gcc for Amiga builds
• amitools (xdftool) for Amiga ADF/HDF image generation

Building

Build the C# projects

Build the solution:

dotnet build linchpin.slnx

Build an individual project:

dotnet build src\Linchpin\Linchpin.csproj
dotnet build src\Chisel\Chisel.csproj
dotnet build src\LP128Pack\LP128Pack.csproj

Build the native C projects

If you are invoking the build from Windows, run these commands inside WSL.

POSIX builds:

cd src/LinchpinST
wsl make clean
wsl make

Target-specific examples:

# Build Linchpin128 as a Commodore 128 disk image
# with a bundled bytecode program
cd src/Linchpin128
make c128-d81 BUNDLE=path/to/bundle.csb

# Build LinchpinST as an Atari ST disk image
cd src/LinchpinST
make atari-disk

# Build LinchpinST as an Amiga disk image
cd src/LinchpinST
make amiga-adf

Running

Linchpin

Inspect an image:

Linchpin inspect --mme path/to/image.mme

Run an image with a database directory, enabling writes:

Linchpin run --mme path/to/image.mme --data YourDB --host-write-files

Disassemble an image to a file:

Linchpin disassemble --mme path/to/image.mme --output path/to/image.cas

Chisel

Assemble an example source file:

Chisel assemble src/Chisel/examples/hello-world.cas --mme hello-world.mme

LP128Pack

Package an assembled image into a bundle for use with the Linchpin128 build:

LP128Pack --mme hello-world.mme --obj hello-world.obj --output hello-world.csb

Testing

Run the test suite with:

dotnet test