WaveformQA VCD Traces

The 13 VCD traces used by WaveformQA, a benchmark for evaluating LLM temporal reasoning over digital signal traces (IEEE ICLAD 2026). The traces were produced by RTL simulation of five open-source RISC-V cores running firmware workloads (~3.3 GB total).

The questions, ground-truth answers, evaluation harness, and per-core generation instructions live in the GitHub repository; this dataset only holds the traces.

Files

A single archive, waveformqa_vcds.zip (~364 MB; ~3.3 GB extracted), containing a LICENSE file (the CC-BY-4.0 terms and third-party attributions below) and one IEEE 1364 VCD file per trace:

Core	Upstream license	Traces	Signal range
DarkRISCV	BSD-3-Clause	darkriscv_coremark.vcd, darkriscv_dhrystone.vcd, darkriscv_mandelbrot.vcd	~394
PicoRV32	ISC	picorv32_custom.vcd, picorv32_dhrystone.vcd	~338
biRISCV	Apache-2.0	biriscv_custom.vcd, biriscv_tcm_soc.vcd, biriscv_tcm_soc_custom.vcd, biriscv_testbench.vcd	1,642-2,295
Ibex	Apache-2.0	ibex_custom.vcd, ibex_dhrystone.vcd	~4,185
SERV	ISC	serv_custom.vcd, serv_hello_world.vcd	~957

Usage

Download the archive, extract it into vcds/ in a clone of the repository, and point the benchmark runner at it:

hf download dcummingsTT/waveformqa waveformqa_vcds.zip --repo-type dataset --local-dir vcds
unzip -o vcds/waveformqa_vcds.zip -d vcds
rm vcds/waveformqa_vcds.zip   # optional: delete the archive once extracted
uv run python scripts/run_benchmark.py benchmark/t5000 --vcd-dir vcds --eval-only \
    -o output/t5000/evaluation_results.json

See the repository README (Getting Started) for the full set of runner flags.

License

Copyright 2026 Tenstorrent USA, Inc.

The VCD traces are generated by simulating the third-party RISC-V cores listed above and are licensed under CC-BY-4.0. Signal names and design hierarchy in the traces derive from those cores, which remain under their own licenses.

The ibex_custom and ibex_dhrystone traces derive from the Ibex core. Its upstream NOTICE file reads:

The Ibex Project
Copyright 2024 lowRISC contributors.

This product includes hardware and/or software developed as part of the
Ibex(R) (https://github.com/lowRISC/ibex) and OpenTitan(R) projects.

Ibex was originally developed by the PULP team at ETH Zurich and University of
Bologna under the name zero-riscy. Ibex verification, performance enhancement
and security hardening have been supported by the OpenTitan project
(https://www.opentitan.org).

The serv_hello_world trace was produced by running the Zephyr RTOS hello-world image shipped with SERV (Zephyr is Apache-2.0). See NOTICE in the repository for full third-party attributions.

Citation

@misc{liu2026waveformqabenchmarkingllmtemporal,
      title={WaveformQA: Benchmarking LLM Temporal Reasoning on Digital Waveforms},
      author={Yichuan Liu and Daniel Cummings and Nick Vadlamudi},
      year={2026},
      eprint={2607.20638},
      archivePrefix={arXiv},
      primaryClass={cs.AI},
      url={https://arxiv.org/abs/2607.20638},
}