CPUlla

CPUlla is a fictional family of 64-bit microprocessors designed to illustrate modern CPU design in educational and research contexts. It was introduced in 2023 by the fictional NovaTech Labs as a reference platform for teaching pipelines, memory hierarchies, and energy efficiency in embedded and edge computing.

Architecture centers on a 64-bit ISA closely aligned with RV64I, augmented by a proprietary low-latency memory extension called XLS. The core uses an 8-stage in-order pipeline, a compact register file, and a straightforward functional unit. The memory system includes 32 KB split instruction and data L1 caches, a 256 KB L2 cache, and optional L3. A coherence-enabled interconnect scales to up to eight cores on a die, enabling simple multi-core experimentation. The design also provides an MMU, a single-precision FPU, and basic virtualization support in demonstration code.

Software and ecosystem: NovaTech released a reference LLVM-based toolchain, a QEMU-based emulator, and a minimal Linux port for CPUlla. The project is intended as an educational tool, with open design documents and reference designs for academic use.

Applications and reception: In teaching labs and simulations, CPUlla is used to illustrate trade-offs between pipeline depth, cache sizes, and energy efficiency. Critics note that, as a fictional platform, it lacks real-world software maturity and hardware availability, limiting practical evaluation, but it remains valued as a clear, coherent example of contemporary architectural concepts.

Variants and future directions: Aimed at different domains, CPUlla-E emphasizes energy efficiency with a smaller die area, while CPUlla-H targets higher throughput through wider issue or vector extensions in later revisions.