Installing PAL capability onto my NTSC A500

[c0dehunter]

Hello All,
How would I be able to install a PAL module (switch?) onto my NTSC A500 (non ESC, original Chipsea), in order to be able to view most PAL Mega Demos properly?

Please refer to this thread:

http://eab.abime.net/showthread.php?...55#post1102655

How would I do this?

[ReadOnlyCat]

NTSC OCS Amiga models are not well suited to run PAL games, even if you switched your NTSC Agnus for a PAL one, the frequency would still be off and you might have issues with some demos which require cycle precise synchronization.

Ideally you would need to switch both Agnus and your main frequency generating crystal (and possibly Denise but I am not sure of that one) in order to have a real PAL machine. This is possible but might be quite convoluted, do you have any experience with soldering?

[TjLaZer]

Originally Posted by ReadOnlyCat

NTSC OCS Amiga models are not well suited to run PAL games, even if you switched your NTSC Agnus for a PAL one, the frequency would still be off and you might have issues with some demos which require cycle precise synchronization.

Ideally you would need to switch both Agnus and your main frequency generating crystal (and possibly Denise but I am not sure of that one) in order to have a real PAL machine. This is possible but might be quite convoluted, do you have any experience with soldering?

Incorrect information!

I had lots of NTSC Amigas and would swith to PAL mode and ALL PAL games and demos would work 100%, especially if I had a good monitor that would display PAL mode. (With Fatter 1MB Agnus)

I use a boxy Commodore 1084S-P monitor and it does PAL/NTSC flawlessly.

[mark_k]

Originally Posted by c0dehunter

Hello All,
How would I be able to install a PAL module (switch?) onto my NTSC A500 (non ESC, original Chipsea)

Are you certain that your A500 doesn't have an ECS Agnus chip? Many did, even though that wasn't advertised at the time.

[idrougge]

Only revision 8.

[zipper]

And rev 6, too (Fat Agnus 8372A)

[idrougge]

8372A isn't ECS.

[zipper]

It is! Done the 1 MB mod to my rev6 mobo.

[DrBong]

Originally Posted by mark_k

Are you certain that your A500 doesn't have an ECS Agnus chip? Many did, even though that wasn't advertised at the time.

Quite right. In transitioning to the A500+, some latter production A500s had rev. 8 boards with ECS (Agnus 8375) when C= were trying to use the remaining old stock of cases and other parts. Consequently, some of the late A500s had odd configs like KS1.3/512K chipram/ECS (see below).

http://www.bigbookofamigahardware.co..._rev8a1_1_.jpg

Some early A500+ owners got shafted with odd configs, with C= populating rev. 8 motherboards with, say, KS2.x and 512K chipram + OCS (instead of 1MB chip + ECS!)

Always worth popping the hood on an A500 and checking (just coz it's made by C=, of course!)......you never know what trash 'n' treasure you may find inside a seemingly boring old standard A500!

[idrougge]

Originally Posted by zipper

It is! Done the 1 MB mod to my rev6 mobo.

That's not ECS Agnus. If that were the case, you would be able to have 2 MB of chip RAM.

[Toni Wilen]

8372A is ECS Agnus, so is 8375. Size of max supported chip RAM is irrelevant. ECS = has new and extended ECS custom registers.

[zipper]

Yes, I ran my A500, Apollo520, WB2.1 on ECS Productivity 640x480 @ 60 Hz - just 4 colours but nice and flicker free workbench. Then craziness hit me and got Micronik tower and Blizzard 2060 + PicassoII+/CVision64/3D/PicassoIV etc...

[DrBong]

Originally Posted by idrougge

8372A isn't ECS.

Originally Posted by zipper

It is! Done the 1 MB mod to my rev6 mobo.

Originally Posted by idrougge

That's not ECS Agnus. If that were the case, you would be able to have 2 MB of chip RAM.

Originally Posted by Toni Wilen

8372A is ECS Agnus, so is 8375. Size of max supported chip RAM is irrelevant. ECS = has new and extended ECS custom registers.

Quite right. Agnus 8372A/8375 revision limits how much chipram can be addressed, but doesn't relate to ECS capability. There's some good info. about this in the links below:

http://www.amiga.org/forums/showthread.php?t=35082

http://www.bigbookofamigahardware.co...t.aspx?id=1478

@c0dehunter
Here's a link that might be helpful re: running PAL demos on NTSC A500s.......

http://ada.untergrund.net/?p=boardthread&id=321

[idrougge]

I stand corrected. I've only seen 8375 or 8372AB in ECS chipset machines.

[Arnie]

The CDTV uses 8372A and has ECS chipset.

[c0dehunter]

Originally Posted by mark_k

Are you certain that your A500 doesn't have an ECS Agnus chip? Many did, even though that wasn't advertised at the time.

If it did, how would I switch from NTSC to PAL then?

[mark_k]

Use Degrader or the NTSC and PAL programs I mentioned in another thread.

Or run AmigaBASIC and type (I think, I didn't try this):
pokew 14676444,32
and then
pokew 14676444,0

If you see any change to the Amiga display you have the ECS Agnus chip. (Those poke commands change to PAL and NTSC mode respectively.)

[DrBong]

Originally Posted by c0dehunter

If it did, how would I switch from NTSC to PAL then?

Originally Posted by mark_k

Use Degrader or the NTSC and PAL programs I mentioned in another thread.

Aye! TUDE is a good alternative also. Both are available on Aminet (see HERE).

Originally Posted by DrBong

@c0dehunter
Here's a link that might be helpful re: running PAL demos on NTSC A500s.......

http://ada.untergrund.net/?p=boardthread&id=321

Here's a better link to a pretty good Amiga beginner's guide written by Shane Monroe, a North American guy who established Dark Unicorn to code shareware games back in the mid-90s. Specifically, check out the "C. Using PAL and NTSC; How to switch your system!" section. He covers various software to best view PAL demos on NTSC machines. Unsurprisingly, he rated Degrader as top of the heap!

http://obligement.free.fr/documents/ami_beg.txt

Anyway, the upshot is that you need to know whether you have an A500 that is capable of changing to PAL before considering something like installing a PAL switcher. Even if you do, it might be better to go the software degrader route as PAL switchers are not as straightforward to rig up on A500s with revision 5 motherboards or lower.

[TjLaZer]

Originally Posted by c0dehunter

If it did, how would I switch from NTSC to PAL then?

Download the commands "NTSC" and "PAL" here and put them in C: then run them from the CLI

http://www.memphisamigagroup.net/dis...2-02/NTSC-PAL/

BootPAL can be used to reboot into PAL mode for NDOS game or demo discs!

[c0dehunter]

You guys are amazing! No wonder Amiga is still alive, it is due to the effort of guy like you that it has been kept alive!