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The ceramic resonator described in this post has been a source of much consternation with the tool-assisted speedrun community. One of the goals of that communi

The ceramic resonator described in this post has been a source of much consternation with the tool-assisted speedrun community. One of the goals of that community has been console-verification of TAS movies, to validate that the runs aren't taking advantage of emulator quirks. If you've ever seen TASbot perform at a GamesDoneQuick event, that's exactly what console verification is doing. The ceramic resonators degrade in accuracy over time (as cited in the article), which leads to non-deterministic performance of the APU, and since the entire console's timings are all linked together, this leads to non-deterministic execution of game code. As a tool-assisted speedrun is essentially a timeline of inputs, there's no logic to account for system execution, and as such, hardware determinism is a requirement. Since an accurate emulator, barring hiccups in the underlying runtime environment, gives us a deterministic runtime environment, this works great. However, it's lead to some weird and awkward behavior when trying to console verify TAS movies on these >30 year old SNES consoles. Replacing these ceramic resonators to repair these consoles has had mixed success, but there are folks that are successfully doing it, thus keeping these legendary consoles alive, and bringing their timings back into spec.

NobodyNada 3y ago
> it's lead to some weird and awkward behavior when trying to console verify TAS movies on these >30 year old SNES consoles. For an example of this, look at this Super Metroid run from SGDQ 2018: https://youtu.be/T_oDcRKzoHI?t=3m17s https://youtu.be/T_oDcRKzoHI?t=3m17s This particular game pauses and waits for the sound engine to “catch up” during door transitions, and the amount of time this takes is nondeterministic due to ceramic oscillators. But the game’s pseudo-RNG continues to cycle in the background during this waiting period, so the nondeterminism impacts gameplay elements such as the steam jets in the timestamped room. That meant that to play back the TAS on a real console, the authors (sniq and total) had to come up with a “polyglot” sequence of inputs that could make it through the room with any possible steam pattern.

NobodyNada 3y ago

> it's lead to some weird and awkward behavior when trying to console verify TAS movies on these >30 year old SNES consoles. For an example of this, look at this Super Metroid run from SGDQ 2018: https://youtu.be/T_oDcRKzoHI?t=3m17s https://youtu.be/T_oDcRKzoHI?t=3m17s This particular game pauses and waits for the sound engine to “catch up” during door transitions, and the amount of time this takes is nondeterministic due to ceramic oscillators. But the game’s pseudo-RNG continues to cycle in the background during this waiting period, so the nondeterminism impacts gameplay elements such as the steam jets in the timestamped room. That meant that to play back the TAS on a real console, the authors (sniq and total) had to come up with a “polyglot” sequence of inputs that could make it through the room with any possible steam pattern.