How to force A1200 Pal in NTSC at boot

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meduseld

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So, I've got the "bad" news that my miggy is a PAL one; works great on my
TV adapter, connected to my computer, but the quality is bad.

Went ahead and purchased a GBS-8220, and it works great, but there is a problem: the Amiga boots up in PAL, and the card won't sync it.

If I use the early setup (pressing the 2 buttons on the mouse at boot), and set it to NTSC, then the GBS works fine.

From what I understand, there is no way to boot in a specific way, unless you go trough the early setup screen, which is impossible to see if you are hooked up to the GBS, since it boots by default on PAL.

Is there an undocumented option at boot, that allows a 1200 with 3.1 roms, to boot directly in NTSC, and that persist even when you shut it down or reboot?

I've found a way to do it via a simple ASM program (it is 4 instructions, the flag is in the ROM so you just have to do a move on one of the register), but that assume that you launch it before the application starts; which makes impossible for me to use floppy games in this way (unless I modify each floppy, adding the program in every disk).

I never tought that PAL/NTSC would be a big deal, since I am using a converter card that should not care about the signal coming in...but it seems that the GBS has this limitation, so either I find a way to boot the Amiga in NTSC, without have to change it every time that I reboot/restart, or I need a way to set the GBS so it can accept NTSC...so far I see no option to change the input system on the card menu, so I am quite stuck.

Any advice? :picard
 
The A1200 have the very same hack as the A500 era: locate the pin 41 of Alice (the Agnus equivalent) and check if it is grounded or put to +5Vdc.

The resistor is a zero-Ohm and is located on the underside of the main board, near Alice.

If it is grounded, remove the resistor. If it is tied to +5V simply remove the resistor and ground the pin using a small wire.
 
I used my GBS only with PAL amigas. Are there really different versions of that board for PAL/NTSC? Maybe there's a jumper or setting for the board?

You would be better off running the Amiga in PAL since most software is written for PAL.
 
i use mine in pal and ntsc,but its only set to one or the other.and not both.

if its set to something your system isent already outputting it can be a little confusing to setup.

ive set mine up so i can use it in pal and ntsc.(both set on the gbs)
 
I see, so there is a hardware hack to do so; but I imagine it requires a bit of skill...the size of these pin is ridiculously small :) I will check the diagrams and see if it is feasible for me to do it...otherwise gotta find a skilled person that may do it :)

velourfog: no jumpers or settings that I can see on the board; I assume that the ones sold here in USA are different from the EU ones; after all this is aimed at owners of cabinet games, so they are mostly tied to the region in which they run(altho makes no sense to me to make 2 different version of the same product, when you can make one and let the user to choose....example: AC adapter that goes from 110 to 230V).

Is also true that 20 years ago there was not that much interconnection between countries as is now...I remember that just to buy an imported console you would have probably done it quicker and cheaper, just flying to JP :)
 
no mate,i didnt use a hardware hack. it can be set to both with the scan function.
 
no mate,i didnt use a hardware hack. it can be set to both with the scan function.

guess we have different software on the GBS then; when I try to do the scan on the pal signal I get nothing usable :) Spent 10 minutes going back and forth trying to change all the values that I can set, and using the auto scan more than once, but it won't hook on any signal other than the NTSC :(
 
thats really odd,maybe its something really obvios.i dont know.
 
thats really odd,maybe its something really obvios.i dont know.

Agree; that's why I decided that maybe was easier to just boot all the time the miggy in NTSC mode, but it seems that there is no way to do so (I wish there was a key that you press at boot to boot in either NTSC or PAL, kinda like you do on a mac :P)
 
is it the 1200 thats in your signature?

you know you can set it to a different screenmode in workbench from harddrive.so it boots to the screenmode you set it to.
 
I thought if you hold a key in early setup screen that it changes between pal and ntsc (for changing without seeing the screen)
 
I thought if you hold a key in early setup screen that it changes between pal and ntsc (for changing without seeing the screen)


it does,you tap any key once and once again to change it back(it cycles)
 
In case you cannot find the "any" key, tapping the space bar helps.

press-any-key-10817013.jpg
 
is it the 1200 thats in your signature?

you know you can set it to a different screenmode in workbench from harddrive.so it boots to the screenmode you set it to.

Yup, that's the one.

Indeed I can change the resolution in WB, but when I launch a game or a demo, it switch to default, so the card goes out of sync. Basically it is usable only on WB

---------- Post added at 02:04 ---------- Previous post was at 02:01 ----------

I thought if you hold a key in early setup screen that it changes between pal and ntsc (for changing without seeing the screen)


it does,you tap any key once and once again to change it back(it cycles)

So i press the 2 button at boot, then I press any key and it will switch between NTSC and PAL? It does not require you to use the mouse and select the option?

That may be annoying but could temporarily resolve the issue! IF only I could find a way to stick the assembly code in the ROM, so I could boot in the other way by default....
 
NTSC mobos @ Vesalia? Not stirring just a suggestion that u may / may not have considered yet mate :)

.aZtOcKdOg | .Key-J FReeLY
 
I came across a key combination a few months back when I was in the early startup menu on my A1200. Can't remember what it was now (sorry :oops:) but I was switching back and fore between PAL and NTSC, which I could then continue booting from.

I think it's either a CTRL or an Amiga key, plus another normal key, possibly even parenthesis or TAB key. My Amigas are all stowed at the moment. I'll try and make some time to dig one out and have a play.
 
are you using whdload for the demos?

yup; don't recall which package is, but was a very nice user that posted 3 archives: one for demos, one for aga games and one for ecs games; all of them for whdload

aZtOcKdOg: That may work if I could swap the mobo :) but they are in EU, and shipping costs are killing me lately :(

ed.D: Thanks! BTW once that you use the key combination in the early startup screen, how do you restart the machine? I don't remember if it swap to NTSC while still in the early setup, so I could not see the screen until it boots up
 
are you using whdload for the demos?

yup; don't recall which package is, but was a very nice user that posted 3 archives: one for demos, one for aga games and one for ecs games; all of them for whdload

aZtOcKdOg: That may work if I could swap the mobo :) but they are in EU, and shipping costs are killing me lately :(

ed.D: Thanks! BTW once that you use the key combination in the early startup screen, how do you restart the machine? I don't remember if it swap to NTSC while still in the early setup, so I could not see the screen until it boots up




you can put ntsc in the tooltypes of the icon,then save it and simply run it by clicking the icon it should open in ntsc:)
 
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