TASEmulators / TASEmulators/BizHawk

Neshawk core emulator inaccuracies

Open
#4,440 0 comments 0 reactions 0 assignees View on GitHub

A pull request for this has already been merged.

  • #4309 by @100thCoin — merged
Core: NesHawk Inaccuracy Repro: Affects 2.10.1 dev
Dominant language
C#
Stars
2.8k
Forks
468
PR merge metrics
No merged PRs in 30d

Description

Summary

In a accuracy test ROM released by 100th Coin, Bizhawk got very high scores, but failed 10 out of 125 tests. These could be interesting to look at and fix.

Repro

Go to the repro below and download the test ROM. Run the tests to see which ones fail.

https://github.com/100thCoin/AccuracyCoin

Output

See youtube video for details. Time stamp is Bizhawk's score screen.

https://youtu.be/oYjYmSniQyM?t=784

Image

Looking at the screenshot these are the failed tests:

  • Interrupt flag latency
  • API register activation
  • DMC DMA bus conflicts
  • Implicit DMA abort
  • Frame counter IRQ
  • Delta modulation channel
  • Controller strobing (or is it Controller clocking?)
  • PPU reset flag
  • OAM corruption
  • RMW $2007 extra write
Host env.
  • BizHawk 2.10.1 (dev)

Contributor guide

Open the contributing guide

First steps

  1. Read the whole issue, then the project's contributing guide.
  2. Comment on the issue to say you are picking it up — it saves two people doing the same work.
  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

Research direction

Start by downloading the AccuracyCoin test ROM from the linked repository and running its 125 accuracy tests against Neshawk. Use the listed failures to identify which emulator behaviors need investigation, then confirm that the affected tests pass without regressing the others. The issue has no source files or test entry points named, and a linked pull request has already been merged.

Written by the indexing model from the issue text.

Assessment

Tech stack
csharp
Domain
game-dev, testing-qa
Issue type
Bug
Difficulty
4/5
Estimated time
3-5 days
Activity status
Stale
Clarity
Mostly clear
Newbie friendliness
25/100

Get new issues in your inbox

A short digest of beginner-friendly GitHub issues.