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PostPosted: Sun May 10, 2015 4:44 pm 
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Im trying to add pal emulation to my emu. Everything is fine but the thing as we know no PC monitors can't generate 50hz.
Maybe this has been asked before, but im a little lazy :x

So how to deal with it??

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PostPosted: Sun May 10, 2015 5:05 pm 
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Good question. I don't know either, but I suppose you're still able to use 60FPS over a 50FPS PPU refresh.


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PostPosted: Sun May 10, 2015 5:23 pm 
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Yeap, but scrolling is not smooth...

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PostPosted: Sun May 10, 2015 8:17 pm 
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I will be more verbose and what i say can be considarated as questions.
Taking into account what the wiki says about PAL:

I'm:

1 - using: 341 × 312 = 106392 as a counter for the frame.
2 - using a float of 3.2 per CPU cycle for the counter above.
3 - 1662607 MHz / 44100 = 37.70~ approx. im getting the sound samples to output. It seems to sound ok.
4 - adding 50 more scanlines (50+20=70) for PAL VBlank.

I think it's allright it decreses speed but the scroll in SMB1 (E) is horrible.
What am i doing wrong?

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PostPosted: Mon May 11, 2015 7:36 am 
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At 60Hz, it would be something like every 5 frames, repeat a frame. So 5 smooth frames, then one jerky one.
At refresh rates which are multiples of 50Hz (like 100Hz), you can do it perfectly.

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PostPosted: Mon May 11, 2015 8:32 am 
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With FreeSync, you can generate 50 pictures per second and push them to the monitor as they are ready. FreeSync is an optional feature of VESA's DisplayPort 1.2a standard first proposed by AMD.


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PostPosted: Mon May 11, 2015 12:15 pm 
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tepples wrote:
With FreeSync, you can generate 50 pictures per second and push them to the monitor as they are ready. FreeSync is an optional feature of VESA's DisplayPort 1.2a standard first proposed by AMD.


The thing Tepples is that is a newer tech and as i read not all GPUs support it nither all monitors. I know that it was adopted as a VESA standard, but it's still pretty new.

Dwedit wrote:
At 60Hz, it would be something like every 5 frames, repeat a frame. So 5 smooth frames, then one jerky one.
At refresh rates which are multiples of 50Hz (like 100Hz), you can do it perfectly.


Here i have an english understanding problem:
So: I DISPLAY 5 frames and the 6th i DON'T display it??

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PostPosted: Mon May 11, 2015 1:24 pm 
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Anes wrote:
Here i have an english understanding problem:
So: I DISPLAY 5 frames and the 6th i DON'T display it??

You display the 6th after you display the 5th again. PAL frames would map to 60Hz like this:

Code:
PC NTSC PAL
01  01  01
02  02  02
03  03  03
04  04  04
05  05  05
06  06  05 (repeat)
07  07  06
08  08  07
09  09  08
10  10  09
11  11  10
12  12  10 (repeat)
13  13  11
14  14  12
15  15  13
16  16  14
17  17  15
18  18  15 (repeat)
19  19  16
20  20  17
21  21  18
22  22  19
23  23  20
24  24  20 (repeat)
25  25  21
26  26  22
27  27  23
28  28  24
29  29  25
30  30  25 (repeat)
31  31  26
32  32  27
33  33  28
34  34  29
35  35  30
36  36  30 (repeat)
37  37  31
38  38  32
39  39  33
40  40  34
41  41  35
42  42  35 (repeat)
43  43  36
44  44  37
45  45  38
46  46  39
47  47  40
49  49  40 (repeat)
49  49  41
50  50  42
51  51  43
52  52  44
53  53  45
54  54  45 (repeat)
55  55  46
56  56  47
57  57  49
59  59  49
59  59  50
60  60  50 (repeat)


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PostPosted: Mon May 11, 2015 3:04 pm 
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Thank you very much. Now it's working

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