Questions about PAL/NTSC compatibility in Amiga games

[arkpandora]

Hi,

A discussion with another member has raised in me the following questions about PAL/NTSC differences in Amiga games :

1. Will any PAL game run on an NTSC Amiga and vice versa ?

2. Which kind of issues may arise ?

Perfect Amiga animation is synchronized with the screen's refresh rate, so :

3. Does it mean that PAL and NTSC animations are coded differently, or will the same version simply play at a different frame rate depending on whether it runs on a PAL or NTSC machine ?

4. If they have different code, does it mean that one version may have perfect animation on the video standard it was designed for, and horrible animation on the other, like when you emulate a 50 Hz PAL Amiga on a 60 Hz VGA screen mode ?

Thank you in advance for enlightening the lost me.

[arkpandora]

Hi there,

Many thanks for your reply.

Then how can the same game give perfect animation both on a 50 Hz PAL screen and on a 60 Hz NTSC screen, as such a quality requires synchronization between the frame rate (hence the code) and the screen refresh rate ?  Is the game played at a different speed ?  But this would lead to some - at least sound synchronization - issues I suppose.

[arkpandora]

Thanks -D-.

Then it would be clearer.

In addition, I suppose that games that use the additional lines of PAL cannot be displayed properly in NTSC either.


The good thing with this hour of the night in Europe, is that you only find NTSC users on Amiga.org...

[arkpandora]

You'll lose me easily again.  Why would you have needed extra Chip RAM in order to run PAL software ?

[arkpandora]

OK - thanks for these informations.

[arkpandora]

Does it work accurately ?  Then would it mean that the CDTV is both PAL and NTSC compatible without any hardware change ?

[arkpandora]

I think that CDTV can play both PAL and NTSC games.

Does it mean that a PAL CDTV can also display NTSC, or that the game has both PAL and NTSC code ?  Does your monitor/TV display the game in NTSC ?


@SamuraiCrow

Do you mean that the composite signal on a non-AGA Amiga is bound to only one standard even if the computer can display both ?

[arkpandora]

Maybe your TV can tell you whether the signal is PAL or NTSC.

At least I suppose there are PAL CDTV and NTSC CDTV, as more than the other Amigae (except the CD32) it was intented to be used on the home TV rather than a monitor, and I suppose that most TVs sold in the USA at that time were not PAL-compatible.

[arkpandora]

I don't know - mystery.

Probably because no video game has ever done that, has it ?

[arkpandora]

@Phantom

As said earlier in the thread, it seems only normal for games to be programmed for either PAL or NTSC, or include both versions in the code (if this situation exists), since each standard requires different coding (at least for animation).

The question is : why does your NTSC game work well on your PAL CDTV ?

[arkpandora]

@Phantom

"Region free" is what I meant by "include both versions in the code".  But also a game or demo may be "region free" if by itself it doesn't use any feature that is specific to only one standard, for example when the software is OS-friendly, or when it has only 200 Low Res pixel lines and no continuous sequence of sounds that is tied to animation (because then sound must be designed for only one animation speed in other words for either PAL or NTSC).  Your "Defender of the Crown" may well fall in the latter category : in that case I suppose that it should be slower than the PAL version, like Rkauer says.


@SamuraiCrow

Thanks.  If I understand, instead of "No" you might have begun by "Yes but", since in my question only the "non-AGA" was wrong - and I had to add "through RGB" at the end.


@rkauer

Thanks for confirming.

[arkpandora]

Darkcoder,

Your comment is very informative and everything is clearer for me now - thank you.