Project Oberon System Ported to RISC-V Architecture for Modern Hardware

A modified iteration of the Project Oberon System has been successfully migrated from its original RISC-5 architecture to the RISC-V (RV32) standard. Hosted on GitHub by user rochus-keller, the project converts source code from Oberon-07 to Oberon 90 and employs the OP2 compiler with a RISC-V backend. This effort aims to preserve the minimalist design principles established by Niklaus Wirth at ETH Zürich while enabling deployment on contemporary, widely available hardware.

The original Project Oberon, developed between 1986 and 1989, was designed to run on the NS32032 processor before Wirth created the proprietary RISC-5 architecture to maintain system simplicity. The new port utilises a virtual machine emulation based on rv32emu, which replicates Wirth’s original hardware design with a one-to-one memory map. This allows core modules such as Kernel.Mod and Display.Mod to remain unchanged, ensuring the system runs natively on the emulated machine across Debian Bookworm Linux, macOS, and Windows.

Rather than extending Wirth’s original OR compiler, the migration reuses the OP2 compiler, which already features an ARMv7 backend. This decision consolidates the toolchain, allowing a single compiler to manage both the migrated Oberon 90 system and the earlier Oberon System 3. The source code, originally downloaded from projectoberon.net in April 2026 with a latest modification date of November 2018, has been adapted to compile with the ActiveOberon project o2c compiler and OP2.

The project targets low-cost microcontrollers, specifically the ESP32-P4 development boards manufactured by Olimex. Because the Oberon system does not require a Memory Management Unit (MMU), it is well-suited for these inexpensive chips. The migration represents a pragmatic approach to bringing the system to modern hardware without compromising the rigorous documentation and simplicity that define the Oberon philosophy.

Future iterations of the project plan to deploy the operating system directly onto the ESP32-P4 hardware. The current repository includes build scripts for Linux, macOS, and Windows, with the virtual machine executable being the only platform-dependent component. This development underscores the enduring relevance of Wirth’s work, bridging the gap between 1990s academic design and current open-source hardware ecosystems.