Author Topic: 8 Mb CHIP RAM on All Amigas (Read 9854 times)

leirbag28 · « **on:** June 02, 2006, 04:03:50 AM »

Why is it possible to have 8mb ChipRAM on WinUAE but not on a Regular Amiga?

As far as I am concerned I belive its possible without even using a gfx card.............I think All an Amiga needs is a WinUAE ChipRAM emulator.

By that I mean surely even a Plain Amiga can emulate the code or instructions that WinUAE uses to be capable of having 8mb ChipRAM..............as long as one has more than 8mb FastRAM to be used as ChipRAM.

Im so sure its possible in one way or another. If not that way...then maybe with an external gfx card kinda like a SUPER Graffitti or DCTV. and of course it being 100% compatible with all software

Its Possible!

whiteb · « **Reply #1 on:** June 02, 2006, 04:23:51 AM »

The Amiga 4000 was to have the 8MB Chip capability, it has got the jumper for it, but 8MB of chip was never implemented.

Winuae has it there for.. reference

.

The A4000 chip ram, uses PC style Simm, but only addresses the 2MB.

DamageX · « **Reply #2 on:** June 02, 2006, 05:19:14 AM »

WinUAE could probably have 1GB of chipmem if the programmer(s) felt like implementing it. But if you want it in real hardware then you need to make a new Agnus/Alice chip with a wider address bus.

motorollin · « **Reply #3 on:** June 02, 2006, 06:50:22 AM »

The 2MB chipmem on real Amigas is a hardware limitation. As DamageX said, if you want to increase the chipmem then you have to replace the hardware.

With WinUAE, they have adjusted the emulation so it can access more memory than a real Amiga, which is why you can have 8MB of chipmem.

--
moto

Oli_hd · « **Reply #4 on:** June 02, 2006, 09:31:34 AM »

Motorollin and the others are right, its the whole AGA/ECS/OSC chipset that would need to be updated to support 8MB, the chip ram address bus is a seperate one from the normal CPU bus and it simply doesnt have enough address lines to support 8MB.

You would need to upgrade all the chipset with one extra address bit to get 8MB chipram and unless you have the AGA designs that aint gonna happen. (And even if you did the A4000 was the only one with the extra address line on the motherboard, so on any other Amiga you would need to run a wire between each custom chip, carrying the extra bit.

The Boxer lifted the Chip Ram limit if I remember correctly, all memory could be assigned as Chip ram if needed.. because the Enhanced AGA chipset had the full 32bit address bus running to it.

for UAE its easy, as they emulate the chipset and motherboard routing so they could make it 32bit if needed.

Oh and why did you post the same question on aw.net?

Piru · « **Reply #5 on:** June 02, 2006, 10:19:45 AM »

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Why is it possible to have 8mb ChipRAM on WinUAE but not on a Regular Amiga?

Emulation of a chipset is not bound to physical limitations of the original.

Quote

As far as I am concerned I belive its possible without even using a gfx card.............

No it is not.

Quote

I think All an Amiga needs is a WinUAE ChipRAM emulator.

By that I mean surely even a Plain Amiga can emulate the code or instructions that WinUAE uses to be capable of having 8mb ChipRAM..............as long as one has more than 8mb FastRAM to be used as ChipRAM.

It means running full UAE on your amiga. Ever tried that? Hint: It is slow. Very slow. Even the fastest classic is way too slow to reach even fraction of A500 speed.

You can't just fork out "chipram emulator", because there isn't one. The whole UAE is required.

Quote

Im so sure its possible in one way or another. If not that way...then maybe with an external gfx card kinda like a SUPER Graffitti or DCTV. and of course it being 100% compatible with all software

No, it is not possible in HW.

Quote

Its Possible!

No, it isn't.

HellCoder · « **Reply #6 on:** June 02, 2006, 12:17:16 PM »

Is it just me or is there once every 6 months a discussion about this ? :lol:

Tricky · « **Reply #7 on:** June 02, 2006, 01:41:59 PM »

If you had an MMU I guess you could use the Fast ram as "virtual" chip ram in the same way it would normally use HD space as virtual memory, swapping blocks of fast ram into chip ram when needed. Although what with the custom chips having direct access to it (do they even go through the MMU?) it would be too difficult to know what chip ram was already in use. Swapping out chip ram the hardware was using might result in some weird happenings.

It would be ok if you were to only use the processor on the extra chip ram, but why the hell would anyone want to do that?

Maybe the OS could be updated so there were extra Exec library functions for declaring chip ram as "asleep" and ok to swap out. But that would mean all the software would have to be rewritten to use it.

foody · « **Reply #8 on:** June 02, 2006, 02:05:24 PM »

Isn't it the same problem as begging and requesting for the Commodore 64 to have more than 64KB of RAM internally? I want my Commodore 64 to have 128 MB of internal RAM and produce more than 16 colors, and I want it to be 16 bit and not 8 bit. As if you are unhappy with what it is and want to change it.

leirbag28 · « **Reply #9 on:** June 02, 2006, 02:35:49 PM »

Im sure most of you are more technically adept than I am.

But I believe it is possible.

Oli_HD wrote:

for UAE its easy, as they emulate the chipset and motherboard routing so they could make it 32bit if needed.
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Ok then, it is time to create UAE for Amiga....to emulate the 32 bit needed for the chipRAM and have the rest of the emulation for everything else run natively since it is a real Amiga.............keeping everything still running smooth :-)

Oli_HD wrote:

Oh and why did you post the same question on aw.net?
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Its posted there also to get more variations of opinions............all the intelligent Amigans dont all necessarily hang out in Amiga.ORG only :-D

Leirbag28 wrote:
Quote:

As far as I am concerned I belive its possible without even using a gfx card.............

Piru wrote:
No it is not.
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Then if it is not possible without a gfx card....it is possible with one as we already know..............so my solution in hardware would be.............create a gfx card thats accessed through RTG I suppose, but isnt a gfx card but only the ChipMem part of it and how it is accessed. And Whalla! you have more chipRAM on an Amiga! and less expencsive than a full gfx card. This would be the equivalent of taking a Picasso Board and leaving all necessary connections but removing the unecessary components and just the ChipRAM and how it is acccessed and all that pertains to it.

Piru wrote:

You can't just fork out "chipram emulator", because there isn't one. The whole UAE is required.
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Well then....one will have to be created to take care of that :-)

Tricky wrote:

If you had an MMU I guess you could use the Fast ram as "virtual" chip ram in the same way it would normally use HD space as virtual memory, swapping blocks of fast ram into chip ram when needed.
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Ah......now we are getting somewhere :-) thanks for open mindedness :-)

foody wrote:

Re: 8 Mb CHIP RAM on All Amigas

Isn't it the same problem as begging and requesting for the Commodore 64 to have more than 64KB of RAM internally? I want my Commodore 64 to have 128 MB of internal RAM and produce more than 16 colors, and I want it to be 16 bit and not 8 bit. As if you are unhappy with what it is and want to change it.
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No, its not the same..............Im happy with my Amiga...and want to keep on being happy with it............since no one is creating New Amigas.............I believe I can at least have my Amiga keep up as much as possible so that I can continue using it with pleasure...............PC's are horrible. If anyting, I will upgrade to an INTEL MAC with Bootcamp to Run Windows XP natively......and Run WinUAE also....and have the best of all 3 worlds..........and all this on a Mac which is definitely more of a pleasure to use that a PC.

Vincent · « **Reply #10 on:** June 02, 2006, 02:54:29 PM »

Quote

HellCoder wrote:
Is it just me or is there once every 6 months a discussion about this ? :lol:

I thought this was a resurrected thread from the last time :-)

utri007 · « **Reply #11 on:** June 02, 2006, 02:55:12 PM »

I belive that is not possible, but

fblit what it does? would it be possible to to assign more memory to graphics with it ?

Maker of it said that he would try to make driver similar like graphicks cards for it?

Fblit have fastest graphics display, compared at any zorro II graphics cards. I've heard that difference is not big to zorro III cards

Napalm is playable with it much faster than any zorro II graphics, if we forget screen flickering

Tricky · « **Reply #12 on:** June 02, 2006, 03:09:41 PM »

Quote

leirbag28 wrote:
Ok then, it is time to create UAE for Amiga....to emulate the 32 bit needed for the chipRAM and have the rest of the emulation for everything else run natively since it is a real Amiga.............keeping everything still running smooth :-)

You can't do that... because the emulator would be using Fast ram to store graphics and sound, which is what chip ram is for. The graphics and sound hardware only has access to chip ram, not fast ram, so you wouldn't be able to use the native hardware, you'd have to emulate that as well. VERY slow. If at all possible on standard ECS/AGA chipset. You'd have to emulate the processor as well to trap accesses to the hardware registers.

You can't emulate just one part of the system, because it's all interconnected, in hardware.

Swapping chip ram into fast ram could be done, as I said, but it would need a new OS to handle it, and an MMU (which isn't standard), and all the programs would have to be rewritten to tell the OS it doesn't need to use that bit of chip ram just now... plus copying large blocks of RAM is slow... especially chip ram... your computer would crawl if it did this on every task switch.

But then you could write programs that work like that anyway, and copy their chip ram into and out of fast ram when needed, without any changes to the OS or hardware.

What you COULD do, however, is make a new OS that can basically run four "virtual amigas" that you can switch between. They wouldn't all be able to run at once though, each one would have its own 2meg chip ram allocation, which gets swapped out when you switch manually from one to the other.

With an MMU maybe it could be made that all four run simultaneously, but you'd only be able to see or hear one at a time.

Piru · « **Reply #13 on:** June 02, 2006, 03:19:53 PM »

@Tricky

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Although what with the custom chips having direct access to it (do they even go through the MMU?)

Nope, only CPU accesses use MMU. Custom chip accesses always access the physical mapping.

Piru · « **Reply #14 on:** June 02, 2006, 03:23:32 PM »

@utri007

Quote

fblit what it does? would it be possible to to assign more memory to graphics with it ?

No.

FBlit just makes all non-displayable bitmaps to reside in fast memory and replace hardware blitting with CPU operations. It doesn't give you any more chip memory, but it reduces usage of it, leaving it for other purposes, and speeding up system (fast memory is, err, faster).

So in a sense FBlit is the best you can get without replacing the whole hardware.

And really, fast gfxcard is much better option, you get truecolor modes aswell.