[ DSP LLE choppy - newly ]

[daaceking]

ive been on that, i don't know what it's for or how to use it. i was hoping for an explanation really,

[Zee530]

Thats the only documentations the devs ever left behind, unless you look at the code, thats as good as it gets

[daaceking]

it's too complicated for me but thanks,

[Shonumi]

Get on the Dolphin IRC channel and ask around. There's usually a dev there. If you have specific questions like "what's the format of GC/Wii textures?" or "what does the memory map for the GC/Wii look like" you can try asking around here (in Development Discussion, preferably) though most of the devs aren't as active here as they are on IRC (I guess).

[NaturalViolence]

Quote:I thought we already established that no one knows XD, just like vbeam

Skid knows, he wrote it.

It emulates vertical display refresh in the VID.

Quote:What is the difference between hle/lle?

i understand it as high/low level emulation.

Why can't you just hle everything? is it a lot of work? impossible?

i mean it would drop requirements. Does it not work like n64/midi?

In the case of dolphins DSP emulator I will provide three different explanations that all mean the same thing:

1.
-HLE emulates the function calls to the DSP API
-LLE emulates the microcode of the DSP

2.
-HLE emulates the DSP at the software level
-LLE emulates the DSP at the hardware level

3.
-HLE emulates the behavior of the game (what the game is trying to accomplish with the DSP)
-LLE emulates the behavior of the DSP itself

Those are three different ways of "looking at it", they all mean the same thing though. I think the last one is the most concise.

Now in general LLE refers to emulating something at the hardware level (mimicking the behavior of the hardware) while HLE refers to emulating something at the software level (mimicking the behavior of the software). There is also a gray area inbetween them as well as hybrid methods that use both.

CPU emulation is always LLE. It has to be since it's not a specialized chip and it runs a wide variety of different code/tasks/jobs.

As for the performance difference between them and how difficult they are to implement that depends on a lot of factors. The amount of documentation available about how the hardware and software work is a major factor in implementation. What the software is doing with the hardware is another major factor. Performance is generally better with HLE methods but HLE methods are generally a lot less flexible and can't achieve the same level of accuracy that LLE methods can. In many circumstances it can be impossible to implement an HLE method or to get it up to acceptable levels of accuracy. In other circumstances it's stupid, pointless, or difficult to implement LLE methods.

Quote:There are some sketchy write ups on googlecode, maybe someone can get you a link? i'm too lazy.

Sketchy? They're written by the same people who wrote the code!

Quote:ive been on that, i don't know what it's for or how to use it. i was hoping for an explanation really,

He gave you one! That entire page is full of explanations. Just click the link at the bottom of the page that says "LLEInformationAndIdead" and it will bring you to this page: http://code.google.com/p/dolphin-emu/wiki/LLEInformationAndIdeas

Which is a perfect guide to everything that you're looking for and fairly straight forward to read/understand.

Here:

Quote:LLE - Low Level Emulation - emulate the hardware behaviour as closely as possible. In case of the DSP, that means running every single instruction just like on the hardware. This contrasts with HLE:
HLE - High Level Emulation. If the large scale behaviour of code running on a device like the DSP is known, we can simply write equivalent C++ code and run that instead of actually trying to run instructions on an emulated DSP. This is how audio has been done in Dolphin thus far, but the limitation is that it can only simulate the "AX" ucode. Advantage is speed, the main drawback is that accuracy is generally not very good and it's easy to miss feature when reimplementing something you don't really know how it works.

It says what you're looking for right there.