Working on a french guide - Questions

Hi to everyone.

Some years ago I wrote several PDF guides for DOSBox french users.
I made three versions, for different users' levels, the most advanced one varied from fifty to fourty pages, including screenshots and drawings.
Since these years, I kept in mind the project of writing similar guides to WinUAE french users.
But as for DOSBox in the past, I'm not sure to understand some options.
So I would like to know if Toni or anybody else could help me ?

My english is not as good as it was when I was student, that's why I only wrote french guides since now.
On the DOSBox forums, some people proposed themselves to translate my guides, but they gave up when they saw the amount of work.
If my english was better, I would translate my work myself.
I can't promise anything but I'll try it. It will need many corrections I'm pretty sure of that.
The goal is to share it with the more people I can and allow emulators autors to correct or to complete me if necessary.
If anyone speaks french, I join the advanced guide of DOSBox to get an idea of what the WinUAE guide would be.

So, there are my questions.

When I set "CPU Emulation Speed" to "Fastest Possible", from what I understand, the emulation of the 680x0 processor will be as fast as my real processor allows it.
The frequency obtained will depend on the power of my real processor. On a less powerful real processor, the frequency will be lower.
Customs chipset will always be emulated at their normal speed.
When I lower the slider, I can lower the frequency allowed by my real processor from 0 to -90 %. And so I lower the CPU load.

About the Interlaced line mode. I'm not sure to correctly understand how the options work.
Double, frames : each frame is separated into two frames, in the first one odd fields are doubled, in the second one even fields are doubled,
Double, fields : each frame gives one frame, odd fields are doubled, even fields are ignored,
Double, fields + : each frame is separated into two frames, in the first one odd fields are displayed, in the second one even fields are displayed, fields are separated by blank lines.

Thank you in advance for your help.

Anyway, I would like to thank Toni for his wonderful work on WinUAE.
Programs like DOSBox, ScummVM, WinUAE, Doomsday Engine, EDuke32 and other emulators / ports are such a blessing for retro-gamers.

When I lower the slider, I can lower the frequency allowed by my real processor from 0 to -90 %. And so I lower the CPU load.

In fact, if I'm correct, when I lower the slider, I limit the real CPU usage to 90 % with -10 % setting, 80 % with -20 % setting... And so I lower the frequency of the emulated CPU.

[Toni Wilen]

Customs chipset will always be emulated at their normal speed.

Yes, chipset speed does not change (at least bitplane and copper). Blitter and disk/audio depends on CPU mode. Audio playback timing is of course always accurate but audio state internal timings are only emulated in cycle exact modes.

In fact, if I'm correct, when I lower the slider, I limit the real CPU usage to 90 % with -10 % setting, 80 % with -20 % setting... And so I lower the frequency of the emulated CPU.

Technically yes but because real CPU timing depends on memory bus speed, caches etc.. which fastest possible mode does not emulate, speed change can't be "converted" to CPU frequency.

About the Interlaced line mode. I'm not sure to correctly understand how the options work.
Double, frames : each frame is separated into two frames, in the first one odd fields are doubled, in the second one even fields are doubled,

No. Odd and even field pairs are combined to single frame, display update rate becomes effectively halved (50Hz -> 25Hz)

Double, fields : each frame gives one frame, odd fields are doubled, even fields are ignored,

No. Odd and even fields are shown alternately. When odd field is shown, previous even field is not changed or erased and vice versa.

Double, fields + : each frame is separated into two frames, in the first one odd fields are displayed, in the second one even fields are displayed, fields are separated by blank lines.

No, again

Same as above but instead of not changing previous field, previous field is blanked. Sort of emulates really really short persistence CRT display.

OK, thank you very much for these precisions Toni.