PAL vs. NTSC

[llcameron]

I'm sure someone around here can finally explain this to me.

Was there such as thing as a PAL version and an NTSC version of the same game? What would a game written in the US look like if played on a PAL VC20 in Germany? Would it look correct? Would something be overscanned or underscanned? Why do screen sizes seem to vary between games (some games have tiny play fields and other it seems like there is no border at all, the full screen is used).

Please, 30 years later, someone explain this and give me peace so that I may finally sleep

[e5frog]

Yes there are games released in different versions and you see it by the screen being offset and not seldom part of the playfield is outside the visible area.

In some games you can move the screen to a correct position (for your VC20) by using cursor- or F-keys, that may differ between programs.

Take Omega Race as an example, the screen can be repositioned with the cursor keys:


IIRC NTSC-games on PAL machines usually have the screen positioned in the upper left corner.


I bought Paratrooper on tape from USA once, that particular game did not have the screen moving function (as far as I could figure out) so I ended up buying the European release as well eventually.

Some games can be patched by setting the right screen coordinates using a hexeditor or similar and save this modified version, this have been done with all the games in the Multi-Cart "Mega-Cart" as far as I know (or perhaps they are patched on the fly so to speak? ).

I patched a few games myself when I hacked a plain VIC-cart to add my favorite BASIC and cart games in a larger ROM, made a small meny and an automatic address slot changer.

[Boray]

In short:

PAL Vic-20: Higher resolution (mostly in height), more flickering, faster computer.

NTSC Vic-20: Lower resolution, more stable picture, slower computer, also capable of interlace mode (which PAL isn't)

And the position of the screen is different.

[folkoh]

In some games you can move the screen to a correct position (for your VC20) by using cursor- or F-keys, that may differ between programs.

Might I add: All Commodore Carts are capable to use the firmware routine of adjusting the screen position with the cursor keys. So no trouble with these NTSC carts running on a PAL VC 20.

Some software companies like Creative also took care of the repositioning with keys. Other carts, e.g. Buck Rogers, don't. Still, if playing on a monitor which allows to center the screen horizontally, this problem can be adjusted. The real problem carts are those NTSC carts using "special effects" that can't be displayed correctly on a PAL VIC, e.g. Demon Attack or Capture the Flag.

Well, as always, the Megacart is the solution to play all carts games on any VIC.

Greetings,

Folko

[Mike]

In the thread 'Would this work? PAL to NTSC converter' I wrote a longer posting about some of the differences between the two TV systems.

I'd like to point out, that it is perfectly possible to correctly re-center the display area, regardless whether the program runs on a PAL or NTSC VIC-20, without requiring user intervention. In the kernal ROM, there exists a table of default values for the VIC chip registers, at $EDE4, which indeed *are* different for PAL and NTSC, but which also allow to calculate the correct values for the horizontal and vertical positioning by adding, or subtracting a constant offset.

For an example, this method is used by MINIGRAFIK, and MINIPAINT, which provide a bitmapped screen of 160x192 pixels - a slightly different geometry from the 22x23 character layout of the text screen. Nethertheless, you can run both programs, and all programs/games written with them, on both PAL, and NTSC VIC-20's, and you will always get a centered display.

[Jeff-20]

...and Robotic Liberation won't run on NTSC.

[eslapion]

... In the kernal ROM, there exists a table of default values for the VIC chip registers, at $EDE4, which indeed *are* different for PAL and NTSC, but which also allow to calculate the correct values for the horizontal and vertical positioning by adding, or subtracting a constant offset.

Which is exactly what I did for the menu program of the Behr Bonz cart so the same code works on both types of VIC-20.

[arkanoid_376970]

...and Robotic Liberation won't run on NTSC.

that sucks... i have the music from RL on my mp3 player. thanks VIZNUT for bringing joy to the C= community! man... i haven't even got a VIC 20 yet

[e5frog]

...and Robotic Liberation won't run on NTSC.

You should get a PAL VIC as well then.

If your TV can take it you can use the same equipment for it anyway.