View Full Version : A500 floppy disks on A1200 and bootblocks

31st May 2008, 06:27
I have just bought an A1200 . already had a A500

When the 1200 is in 1.3 Kick mode, I only have one game disk that runs correctly:(

It's an Emerald Mine disk that states "runs in any Amiga"

Would this be because the bootblock is a universal one, or will it be more extensive changes to the game???

If its the bootblock, can I simply copy it to other games?

Can I get more universal bootblocks on the web?

Or am I on the wrong track


31st May 2008, 09:54
Welcome to the Classic Amiga Forum Noel,

I can give you some pointers but there are people on here that eat, drink and sleep Amiga's!! (no offence guys) :)
What I am saying is I am no expert.

Can I ask you do you have a hard drive?

Do you have a means to transfer files from another machine, EasyADF, Catweasel, etc.
You have to remember the A1200 is a different beast compared to your old 500, you have the AGA chipset that make ordinary games that used to play in a A500 impossible - this may be caused by a root/boot block (help me out here guys) or simply the AGA chipset won't allow old OCS games to play but have you heard of WHDLoad? http://whdload.de/ or the KGWHD collection? Our nice administrator chappy has uploaded the entire collection on the main site.. Amiga/downloads you will need to login in to download them...

With WHDLoad you will find its the standard on the A1200 these days to get our old favourites to run nowadays on a hard drive.

Also on another note, please support WHDLoad and register your copy if you like it - its only 15 pounds via PayPal.

Whether oldies or newbies, experts and Emulator people - we stick together and help each other out and you will find that out and you have come to the right place. :)

Why don't you write an introduction about yourself in 'member introductions'

Once again, Welcome. :)


31st May 2008, 10:12
Hi there Noelozzy,

Welcome to the Classicamiga forum!

Congratulations on purchasing an Amiga 1200. I'm tempted to ask the same question as Castelle; Do you have a harddrive for it and what are the other specs?
If you don't have a harddrive, I would strongly recommend you getting one. The machine is much, much better with it than without it. It's cheap as well, as you can pick up older 2.5" drives almost for free. You can also use a Compact Flash adapter with a suiting card.

I see that you mention the 1200 running in Kickstart 1.3 mode. Are you using ReloKick, or are you using the degrading options in the boot menu? ReloKick is a software kickstart booter, which loads the 1.3 ROM into the machines memory. It makes many titles available for 1200 users.

The boot menu of the 1200 (hold down both mouse buttons during startup to access this menu), you can change chipset to original, turn off CPU caches, which can be of help when it comes to running older software. Here you aren't running the Amiga in 1.3 mode, but with more compatible settings.

If you have a harddrive and are trying to run games from it, there are plenty of degrading tools available on Aminet. I've used programs such as Degrader and KillAGA with some success. But one must mention, as Castelle did, the awesome WHDLoad. :) Using this tool, you can easily run old 500 titles, and you don't even have to change floppies. ;)

Hope this was of some help. :)

31st May 2008, 10:48
Would this be because the bootblock is a universal one, or will it be more extensive changes to the game???

Hi and welcome to the forum.

As the others have said, older games written specifically for the A500 might not always work in the A1200 as standard. This isn't to do with the bootblock on the floppy disks. Those should be able to be read by any Amiga model. The issue is due to the difference in the hardware between the A500 and the A1200.

Many A500 games developers were a bit naughty. To squeeze as much as they could out of the hardware they bypassed the standard programming rules and coded directly to the hardware. This is fine on a real A500 but if you try to run such games on other Amiga models they can fail. This is due to each model having different amounts of chip ram, a different processor or a different custom chipset to the A500.

As an example of what might cause a game to not work in the A1200. If for example the developer coded some of a game's routines so they accessed specific memory addresses on the A500, then this would cause the game to crash on the A1200 because the memory addresses for the 2MB of chip ram and the wider CPU address space of the A1200 would mean the memory addresses the game was looking for are in a different place and it wouldn't be able to find them.

The good news is that most games can be made to work on the A1200. And as PG has already mentioned you can often do this using a disk called ReLoKick 1.3. This loads the Kickstart 1.3 rom from an A500 into the A1200's memory and then reboots the A1200 so it loads up thinking it is a 1.3 A500 (until the next reset). This disk can often get many older games to work properly with the A1200. If you need a copy of this disk PM me for further details.

Also as already mentioned you can hold down both mouse buttons as you switch on the A1200 to access a boot menu. In here by simply disabling the memory cache you can often get many games to work. I would say this simple method got around 80% of all the games working that I had problems running on the A1200.

Finally there are many other degraders that will get games to work. TUDE, KillAGA, Degrader etc...

Except again as already mentioned, you would be better off if you have a harddrive in the A1200 and some fast ram installed in the trapdoor. Then you can install WHDLoad. This is a harddrive games installer and it allows you to install pretty much any Amiga game onto the harddrive, not just ones that are HD installable, but all games. This is possible because the WHDLoad supporters write install scripts for each game.

The advantage of using WHDLoad is that it includes downgrader support for older games, so most games that won't normally run on an A1200 will run when installed using WHDLoad.

I hope some of that info helps.

Please ask if you need more help and advice for WHDLoad and the ReLoKick 1.3 disk.

31st May 2008, 22:50
Thanks for all the replies.

Yes my 1200 has a HD i think its 40M

And yes I use Relokick to load the 1.3 Kickstart.

I understand that WHDLoad will perhaps run my games from the HDD

But I wish to prove or disprove if its the bootblock loader making the difference

When i was into Amiga in the past, everyone had Emerald Mine on the A500, I vaguely recall something about the bootblock loader, its so long I am out of touch, have to learn how to try this bootblock that works on other disks.

Thanks to Harrison, PG and Castelle:yesyes:

1st June 2008, 00:06
The boot block will most likely be a custom one for nearly every commercial game disk you look at because the developers tended to write a specific custom disk format for their games that was aimed at getting the most onto a disk, but at the same time arranging it in an order that optimised the loading of the contents. Therefore most game boot blocks were written to take control of memory and resources to suit itself, effectively disabling AmigaOS and the Amiga GUI.

I think for most Emerald Mines games the disks are generally AmigaDOS based, normally containing standard boot block code to load the 'dos.library' (AmigaDOS) and then exit to it, invoking the GUI.