A2630 & autoconfig space

[clemenza]

Hi! I've encountered a problem while installing a Commodore 2630 and a memory expansion in my A2000. The 2630 has 2 megs of fast RAM installed and my memory expansion card has 8MB of RAM. If I install both of the cards, my A2000 'sees' only 2MB of fast RAM (the memory of the accelerator) probably because I have 10MB of RAM in the autoconfig space. If I disable the RAM of the accelerator then I have 8MB of fast RAM (the memory of the memory expansion card) but the computer is much slower - almost as if the CPU was an 68000. To confirm this I ran sysinfo: with the memory of the 2630 enabled my A2000 had almost the same speed as the stock A3000 (not bad at all!). When using the memory of the expansion card sysinfo showed me that my A2000 had almost the same speed as the stock (68000) A2000! So, does anyone know how can I use the memory of the memory expansion without disabling the memory of the 2630?

[fiat1100d]

You should reduce the amount of Fast RAM on the expansion board... I don't think 6 MB is an option, so 2 MB or 4 MB. Then you may consider installing a full 4 MB on the A2630 for example.

[clemenza]

Yes, I did reduce the amount of RAM on the expansion board to 4MB resulting in 6MB of fast RAM but then I had system crashes when running Miami & Ibrowse (I also have an X-Surf III installed). I don't understand why is the A2000 so slow when disabling the fast RAM of the 2630 (and using the full 8MB of the memory expansion)

[DoogUK]

The ram on the a2630 is full 32 bit so you should have that in use.
Their might be a small amount of ram on one of your other cards topping you over the 8mb limit therefore causing your slowdown/crashes.
I have 4mb on my a2630 and 4 on my hc+8....and it runs sweet.
As suggested use the accelerator ram and reduce the slower ram on your expansion.

[clemenza]

OK, thanks, that's exactly what I'm trying to do - but I still can't understand why it crashes! I have no other cards like GFX or bridgeboard installed (only a Buddha IDE controller). And what's the reason for the memory on the memory expansion board (3-State Megamix) being so slower than the memory on the A2630?

[fiat1100d]

A2630 without its Fast RAM is slow because other expansion RAM is 16-bit wide while the A2630 one is 32-bit wide, plus it is directly connected to the CPU while the other memory is accessed through the Zorro II bus and that increases the latency...
The system shouldn't crash with 2 + 4 MB of memory, strange issue, I am sorry I can't help about that :-(

[clemenza]

Thanks, anyway. I'll try using another memory expansion that I have (I think it's a MultiMegaCard or something like that). I believe it will work after all! It's a pity though not having enough fast RAM as my A2000 has the minimum amount of chip RAM too - it's an old OCS model...

[CLS2086]

Hi,
So you have :
A2630 - 2mb  -> so 6 mb left of Z2 space
Buddha IDE - 128kb -> so a bit less than 6 mb left of Z2 space
Ramcard rom - 64 kb -> so a little more than 5.5 mb left of Z2 space
So reduce your ramcard's ram to 4 mb.

[rkauer]

 I think the issue is related to the way "autoconfig" works: even a small portion of memory (like the ones reserved from the Buddha) can fragment the autoconfig space, resulting in no sufficient room for the 4Mb RAM card.

 Use only 2Mb on the expansion card and use the "powerful" 4Mb on the A2630 accelerator.

 If you want more RAM in your system, go for a better accelerator or a DKB 3128 or that other one who accepts 64Mb (don't remember the name right now).

[Piru]

@rkauer

DKB 3128 is a Zorro III card. You can't get more than 8MB thru Zorro II, so better accelerator with onboard memory is the only option.

[mongo]

Piru wrote:
@rkauer

DKB 3128 is a Zorro III card. You can't get more than 8MB thru Zorro II, so better accelerator with onboard memory is the only option.

A DKB 2632 will allow you to add up to 112MB to an A2630.

[rkauer]

 Oooops!:oops:

 @Piru: thanks for the correction!

[clemenza]

Well, finally it works with the following configuration: 2MB fast RAM on A2630 + 4MB fast RAM on MultiMegaCard + 2MB fast RAM on Megamix 2000 = 8 MB fast RAM working flawlessly! Sysinfo shows that my A2000 has now almost the same processing power as the stock A3000! After that, I added an Algor Pro and installed Fblit and WBctrl resulting in almost 400 KB of free chip memory! (that's why I wanted the 'full' 8MB of fast RAM!).