Making an OCS A2000 (Rev 4.6) to an ECS A2000

Drake008@ · 27 February 2007, 19:52

Is that possible?

Jope · 27 February 2007, 19:57

It is, if it has the PLCC Agnus.

The board will take a 1MB Agnus natively + the super Denise is pin-compatible with the old one. If you want 2MB CHIP, you need a Mini Megi board or similar.

[edit: Denise not Senise :-)]

Drake008@ · 27 February 2007, 20:02

Quote:

Originally Posted by Jope

It is, if it has the PLCC Agnus.

The board will take a 1MB Agnus natively + the super Senise is pin-compatible with the old one. If you want 2MB CHIP, you need a Mini Megi board or similar.

And that's the thing I'm searching for. Do you know where to get this Chip?

After that one is put in the old Agnus Slot and this little wire is put on a pin at the Gary I got ECS?

Jope · 27 February 2007, 20:47

You get half of ECS that way. Then you need the Super Denise to get all the ECS screen modes.

Although I think you're only interested in 2MB CHIP RAM?

You can get the NTSC minimegi from Vesalia, but I don't know if that's easy / hard to convert to PAL.

Drake008@ · 27 February 2007, 21:32

Quote:

Originally Posted by Jope

You get half of ECS that way. Then you need the Super Denise to get all the ECS screen modes.

Although I think you're only interested in 2MB CHIP RAM?

You can get the NTSC minimegi from Vesalia, but I don't know if that's easy / hard to convert to PAL.

Even that one isn't in stock. I know it stands there with a price. i called them last week and asked for a PAL or the NTSC version and both arn't available anymore.

alexh · 27 February 2007, 21:36

To change an NTSC MiniMegi into a PAL you need to replace the (8375) 318069-11 Agnus chip with the 318069-10 variant.

Which kinda defeats the purpose of buying one in the first place if you ask me.

Drake008@ · 27 February 2007, 21:43

Do you got the Agnus number for PAL and maybe the new Denise number (or isn't there any).

Jope · 27 February 2007, 21:49

Argh! The schematics on the internet are total crap.

No chance in checking out how the Agnus pinouts differ. And all my manuals are in another town right now. I have the A500 and A500+ schematics on paper in my archives..

Jope · 27 February 2007, 21:51

Get a 8372A Agnus and the Denise is 8373R4, those are safe to plug in directly.

Drake008@ · 27 February 2007, 22:06

This one is in my A2000 and to get to 2 MB I need the 8375, I think. Or isn't that necessary to get to ECS?

I copied a list for all the Agnus:

8361 : Agnus, 512KB ChipMem, NTSC, US-A1000, US-A2000A
8367 : Agnus, 512KB ChipMem, PAL, A1000, A2000A
8370 : Agnus, 512KB ChipMem, NTSC, US-A2000, US-A500
8371 : Agnus, 512KB ChipMem, PAL, A2000, A500
8372A : 318069-02: Agnus, 1MB ChipMem, PAL/NTSC, A2000, A500
8372B : 318069-03: Agnus, 2MB ChipMem, PAL/NTSC, A3000
8375 : Different Version:
390544-01: Agnus, 2MB ChipMem, PAL, A500+, A600
390544-02: Agnus, 2MB ChipMem, NTSC, A500+, A600
318069-03: Agnus, 2MB Chipmem, replaces 8372B
318069-16: Agnus, 1MB ChipMem, PAL, replaces 8372A
318069-18: Agnus, 2MB ChipMem, PAL, replaces 8372B

alexh · 27 February 2007, 22:15

You CANNOT use just any Agnus. They are not electrically compatible.

Put the wrong one in and you will KILL your Amiga.

That list is incomplete and innacurate by the way... dunno where you got it from

Jope · 27 February 2007, 22:16

The 1MB Agnus is also ECS, but it just addresses less RAM.. Hence my question.. Do you want 2MB CHIP or ECS (or both)?

If you want the 2MB, just try and find a Mini-Megi board.

If your primary target is ECS, then you can just get the 1MB Agnus and a Super Denise.

If 2MB + Full ECS, get the Mini-Megi and the Super Denise. :-)

Drake008@ · 27 February 2007, 22:18

But how did they get 2MB Chip-Ram working when there is no Agnus for the A2000 known (on my sites I found!) which provides that feature.

Of course, I want both

. And those MiniMegis (MiniMegas) are very expensive and rare on eBay (more than the new ones!). Maybe I should look for a A2000 Rev 6.5 Board.

Jope · 27 February 2007, 22:19

With an adapter that converts the 8375 to look like a 8372 and which has a little GAL chip to handle the address decoding for the extra 1MB of RAM on the adapter board.

alexh · 27 February 2007, 22:20

Wot he said, although I dont think that "converts it to look like a 8372" is an accurate description.

MiniMegi (or one of the 3 others) is the only way to get 2Mbyte Chip RAM on an A2000. But why would you want it?

Drake008@ · 27 February 2007, 22:24

Quote:

Originally Posted by alexh

Wot he said, although I dont think that "converts it to look like a 8372" is an accurate description.

MiniMegi (or one of the 3 others) is the only way to get 2Mbyte Chip RAM on an A2000. But why would you want it?

Good question, isn't that necessary? Everyone says it's a must-have.

27 February 2007, 19:52	#1
Drake008@ Registered User Join Date: Jun 2006 Location: Germany Age: 45 Posts: 132	Making an OCS A2000 (Rev 4.6) to an ECS A2000 Is that possible?

27 February 2007, 19:57	#2
Jope - Join Date: Jul 2003 Location: Helsinki / Finland Age: 43 Posts: 9,861	It is, if it has the PLCC Agnus. The board will take a 1MB Agnus natively + the super Denise is pin-compatible with the old one. If you want 2MB CHIP, you need a Mini Megi board or similar. [edit: Denise not Senise :-)] Last edited by Jope; 27 February 2007 at 20:46.

27 February 2007, 21:36	#6
alexh Thalion Webshrine Join Date: Jan 2004 Location: Oxford Posts: 14,331	To change an NTSC MiniMegi into a PAL you need to replace the (8375) 318069-11 Agnus chip with the 318069-10 variant. Which kinda defeats the purpose of buying one in the first place if you ask me. Last edited by alexh; 27 February 2007 at 22:16.

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Wanted: Indivision ECS (Or other A2000 scandblr/flickfix)	8bitbubsy	MarketPlace	2	03 August 2011 21:10
Looking For Indivision ECS For A2000 System	Loedown	MarketPlace	3	25 April 2011 12:40
Help for A2000 rev 6.4 board!	genny	support.Hardware	3	16 April 2011 05:26
A2000 Rev 4?	Fingerlickin_B	support.Hardware	29	08 October 2010 19:29
Help reviving A2000 rev 6.2	gdanko	support.Hardware	2	06 August 2006 12:03

27 February 2007, 20:47	#4
Jope - Join Date: Jul 2003 Location: Helsinki / Finland Age: 43 Posts: 9,861	You get half of ECS that way. Then you need the Super Denise to get all the ECS screen modes. Although I think you're only interested in 2MB CHIP RAM? You can get the NTSC minimegi from Vesalia, but I don't know if that's easy / hard to convert to PAL.

27 February 2007, 21:43	#7
Drake008@ Registered User Join Date: Jun 2006 Location: Germany Age: 45 Posts: 132	Do you got the Agnus number for PAL and maybe the new Denise number (or isn't there any).

27 February 2007, 21:49	#8
Jope - Join Date: Jul 2003 Location: Helsinki / Finland Age: 43 Posts: 9,861	Argh! The schematics on the internet are total crap. No chance in checking out how the Agnus pinouts differ. And all my manuals are in another town right now. I have the A500 and A500+ schematics on paper in my archives..

27 February 2007, 21:51	#9
Jope - Join Date: Jul 2003 Location: Helsinki / Finland Age: 43 Posts: 9,861	Get a 8372A Agnus and the Denise is 8373R4, those are safe to plug in directly.

27 February 2007, 22:06	#10
Drake008@ Registered User Join Date: Jun 2006 Location: Germany Age: 45 Posts: 132	This one is in my A2000 and to get to 2 MB I need the 8375, I think. Or isn't that necessary to get to ECS? I copied a list for all the Agnus: 8361 : Agnus, 512KB ChipMem, NTSC, US-A1000, US-A2000A 8367 : Agnus, 512KB ChipMem, PAL, A1000, A2000A 8370 : Agnus, 512KB ChipMem, NTSC, US-A2000, US-A500 8371 : Agnus, 512KB ChipMem, PAL, A2000, A500 8372A : 318069-02: Agnus, 1MB ChipMem, PAL/NTSC, A2000, A500 8372B : 318069-03: Agnus, 2MB ChipMem, PAL/NTSC, A3000 8375 : Different Version: 390544-01: Agnus, 2MB ChipMem, PAL, A500+, A600 390544-02: Agnus, 2MB ChipMem, NTSC, A500+, A600 318069-03: Agnus, 2MB Chipmem, replaces 8372B 318069-16: Agnus, 1MB ChipMem, PAL, replaces 8372A 318069-18: Agnus, 2MB ChipMem, PAL, replaces 8372B

27 February 2007, 22:15	#11
alexh Thalion Webshrine Join Date: Jan 2004 Location: Oxford Posts: 14,331	You CANNOT use just any Agnus. They are not electrically compatible. Put the wrong one in and you will KILL your Amiga. That list is incomplete and innacurate by the way... dunno where you got it from

27 February 2007, 22:16	#12
Jope - Join Date: Jul 2003 Location: Helsinki / Finland Age: 43 Posts: 9,861	The 1MB Agnus is also ECS, but it just addresses less RAM.. Hence my question.. Do you want 2MB CHIP or ECS (or both)? If you want the 2MB, just try and find a Mini-Megi board. If your primary target is ECS, then you can just get the 1MB Agnus and a Super Denise. If 2MB + Full ECS, get the Mini-Megi and the Super Denise. :-)

27 February 2007, 22:18	#13
Drake008@ Registered User Join Date: Jun 2006 Location: Germany Age: 45 Posts: 132	But how did they get 2MB Chip-Ram working when there is no Agnus for the A2000 known (on my sites I found!) which provides that feature. Of course, I want both . And those MiniMegis (MiniMegas) are very expensive and rare on eBay (more than the new ones!). Maybe I should look for a A2000 Rev 6.5 Board.

27 February 2007, 22:19	#14
Jope - Join Date: Jul 2003 Location: Helsinki / Finland Age: 43 Posts: 9,861	With an adapter that converts the 8375 to look like a 8372 and which has a little GAL chip to handle the address decoding for the extra 1MB of RAM on the adapter board.

27 February 2007, 22:20	#15
alexh Thalion Webshrine Join Date: Jan 2004 Location: Oxford Posts: 14,331	Wot he said, although I dont think that "converts it to look like a 8372" is an accurate description. MiniMegi (or one of the 3 others) is the only way to get 2Mbyte Chip RAM on an A2000. But why would you want it?

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)