[A83] Re: Grey scale(and enterlacing,is that the right word for it?)


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[A83] Re: Grey scale(and enterlacing,is that the right word for it?)




I don't think VTI uses fade out, I think, like I said earlier, it works like
this. For example, the LCD update freq. of the VTI is 30 Hz and it 'reads'
from the video ram every 1/120th of a sec (u have to set fixed font to see
this gooed)
Seconds
0....|....|...0.1...|....|...0.2...|....|....|...0.3...|
VTI update               |    |    |    |    |    |    |    |    |    |    |
|
Pixel in video RAM
|0000|1111|0101|1010|0001|1000|1010|1111|0000|1011|0111|   etc....
Color in % black         | 0% |100%|50% |50% |25% |25% |50% |100%| 0% |75%
|75% |

The fact that you see the cursor fading out a bit sometimes, is because of
this:

VTI update               |    |    |    |    |    |    |    |    |    |    |
|
Cursor on/off
|1111|1111|1111|1111|1111|1111|1111|1110|0000|0000|0000|   etc....
Color in % black         |100%|100%|100%|100%|100%|100%|100%|75% | 0% |0%
|0%  |
                                                              ^
                                                              |- grey

So, when u see grayscale flickering on VTI, it means that the pixel switch
frequency is not working good with the LCD frequency eg the pix freq = 45 Hz
and the LCD 30 Hz.

Bye
Cheiz


> The way you descibed (fade out) is/was already implemented in VTI 2.5 beta
> 4 & 5. What did you mean with "VTI does grayscale by cheating.  It does
not
> support grayscale on the 82 line of calcs.  It watches for the video ram
> port being switched, and if it's in a grayscale pattern, it displays
> grayscale."
>
> I guess you meant to say that VTI does this "video ram port"-trick with
the
> 'higher' Ti calcs? btw, shouldn't it do the fade out too then? Else it
> would cause tremendous flicker on your monitor...

> Henk Poley <><
>
>
>