Yamaha YMF7xx emulation

[klerg]

Hello

I'm wondering if it will be possible in a future version to emulate the Yamaha YMF7xx series sound card. Here is some more information about the sound chip:

https://en.wikipedia.org/wiki/Yamaha_YMF7xx

If anything more is needed I can provide some more links. I do not own any Yamaha YMF7xx sound cards, but I''m sure others do. I hope Yamaha will not get in the way of this. Some help would be great.

Thanks a lot

[leilei]

viewtopic.php?f=2&t=3604

[klerg]

Great that Yamaha YMF7xx is being considered but looks to be a long way from anything real. Wish I could help but this is beyond my skills not even sure what 'HLE' means for starters.

[Cheez]

High Level Emulation. I don't really know quite how to put it into layman's terms but consider it like the difference between knowing an engine drives the car, and knowing the internal components of the engine that drive the car. In high level emulation you're trying to reproduce the surface level behavior, but in low level emulation you're trying to reproduce the mechanism behind it in order to catch edge cases. The "higher" you go, the faster things will run, but the more unexpected results can occur, especially from a non-standard usage of the thing in question. The "lower" you go, the more accurate the emulation can be, but at the cost of speed as there's a simulation of more and more "parts" or the specific quirks and interactions of them.

[klerg]

I knew HLE was short for something. And not surprised it is High Level Emulation. This sounds a bit too complicated for me. So is knowing an engine drives a car the high level emulation, and the internal components of the engine going to be low level emulation? So for sound card emulation is high level or low level emulation preferred or better? What is meant by edge cases and is that needed to emulate the Yamaha YMF7xx? I assume for a sound card accuracy is more important than speed, but I could be way off here. To me it looks like high level emulation is easier to pull off than low level. Can you give an example of something that is emulated on low level vs. a high level emulation?

[Cheez]

I don't have any readily available examples, but I know that Nintendo 64 emulation is notorious for being difficult to emulate, and low level emulation was a sort of holy grail to get a lot of games that used peculiar hardware tricks to run properly. But, yeah. As far as I know, High level emulation is "It works, but probably not the in the way it was designed" and low level emulation is "we've got many or all of the finer details of how this thing works and we're doing it that way". It can be harder to do if you have to reverse-engineer something instead of having the design on hand. Sorry if I'm making this hard to understand but I'm pretty bad at explaining things decently.

[JosepMa]

In the context of emulators, high level emulation would be:
- Programs were told they have these instructions that they can use to obtain these results and we will implement something that generates those results
and low level emulation would be:
- We have the knowledge of this specific hardware implementation that implements those instructions to generate the results that programs expect and we will emulate the way it does so.

When the implementation is not fully known (or not at all), having the actual hardware to test corner cases is helpful.

[klerg]

Sure that is fine will try to find some myself. Also it is very hard to emulate the XBox and that is just the original one. I think low level programming and high level programming differ in a similar way to low level emulation and high level emulation. Both low level programming and emulation deal with the hardware and software intimately, but LLE interacts with them with less detail. For high level programming and emulation both communicate with hardware on an occasional basis, and HLE has the added quirk that it does not work the same as whatever it is emulating. It's ok HLE and LLE are not easy to explain at all.

Yes that is in a nutshell what I could take out of high level emulation that it tries to emulate something by not actually working in the same manner as the original source. And low level emulation is the exact opposite in that it is a carbon copy of whatever it is emulating and as such is more accurate than HLE. But high level emulation has the bonus of being faster. Not sure when one uses HLE or LLE. I know the Gravis Ultrasound is emulated by PCem, is that using HLE or LLE? I hope the Yamaha YMF7xx can be done just like the GUS, but I really have no clue.

This is why i'm looking to get any YMF7xx but many have it. To make electronic or game music it is a must have sound card.