Deleted, due to other thread started with same question.

I read that only 1.5gb of an max. installed 2gb of RAM can be addressed by MorphOS, is this true? It yes, that surprises me as that has been one of the AmigaOS's strong points since the day it was first introduced, that it could address more RAM than was physically possible to install in any of the Amiga models.

Given the low memory usage of MorphOS, I don't see that the 1.5gb limitation to be a problem, but just found it surprising that MorphOS was not designed to take advantage of more from it's beginning, or is this only a problem with the implementation of MorphOS on Apple's PowerMac models?

[ Edited by amigadave on 2009/12/2 7:19 ]

@amigadave

I believe the RAM limitation is a result of MorphOS' duplication of the original Amiga OS api - warts and all as it were

[ Edited by Ruud on 2009/12/2 15:43 ]

Quote:

Exactly, so long as it works in Morph! I used this card a lot in PC running programs such as Cakewalk Sonar and even Kompleat. While not the greatest audio chip (EMU10K), it did run quite well for me and under extreme loading. Regarding the MorphOS drivers for this card, what portion of this soundcard's hardware is supported?

On another note, I need to come to grips with AHI. I obviously utilize it in MorhpOS2 and also in PC emulated 68K. What is it really doing in Morph? Is this just an API for non-Amiga hardware deal? Also looks like it has driver integration. In reading its documentation it seems decent enough if used natively inside programs using audio.

[ Edited by Rodomoc on 2009/12/2 10:30 ]

> that surprises me as that has been one of the AmigaOS's
> strong points since the day it was first introduced, that it
> could address more RAM than was physically possible to
> install in any of the Amiga models.

Yes, and "now" technology has advanced so far that the physically installable RAM exceeds the amount that is addressable by AmigaOS (and API clones) since the day it was first introduced. Not really surprising ;-)

> found it surprising that MorphOS was not designed
> to take advantage of more from it's beginning

Ruud is on spot here: More RAM addressability would have broken the AmigaOS API compatibility of the ABox.

> or is this only a problem with the implementation of MorphOS
> on Apple's PowerMac models?

No, that would lack any technical reason.

> What is it really doing in Morph? Is this just an
> API for non-Amiga hardware deal?

I don't quite understand. AHI is the audio API of MorphOS. Audio hardware needs an AHI driver for MorphOS to utilize that hardware. MorphOS itself comes with AHI drivers for Pegasos onboard sound, Efika onboard sound and Mac mini onboard sound.

Yep, I read through all AHI docs and understand this a lot better now.

thanks for the answers Andreas & Ruud. My memory of just how much RAM the original AmigaOS could address is a bit fuzzy, though I was pretty sure it was over 1gb and thought it might be 2gb.

I did not know for sure that increasing that original limit in MorphOS would break all compatibility with legacy Amiga software, so that is also an interesting bit of info.

I wonder if MorphOS will survive long enough to evolve past the original Amiga limitations, like the MacOS has, but still be able to run some of the older software, perhaps only via a version of UAE in the distant future.

For the interested ones, the guilty function is exec.library/AllocEntry(). Short extract from its autodoc: "The result is unusual! Bit 31 indicates failure."
So, at max, only 31 bits (0 to 30) can be used to represent an address. And 2^31 is 2GB.

I am a little confused about the original post. It says, "MorphOS also runs on PowerMAC G4 systems now". Does that mean that 2.4 runs on the PowerMac already or am I reading this wrong.

Thanks - J

@jclausen

Read the last paragraph of the original post.

@henes,

Then shouldn't MorphOS be able to use the whole 2gb of RAM installed in a G4 PowerMac?

I have a powermac g4 @ 400mhz but the "problem" of this macs is the exclusive expansion cars like the gfx one.

Very nice!

Quote:

The 2 gb include also teh address space for devices, thus it is less than 2 gb (I thought actually it would be around 1.8 gb)

> I thought actually it would be around 1.8 gb

https://morph.zone/modules/newbb_plus/viewtopic.php?topic_id=6634&forum=3#67586

> I have a powermac g4 @ 400mhz but the "problem" of this macs is the
> exclusive expansion cars like the gfx one.

Can't you simply swap the GFX card for a MorphOS supported one?

I have a radeon 9200 agp but if i pluged it on the powermac havent any video signal.

that's probably because pegasos machines has x86 emulation for gfx cards bios, while powermacs doesn't. afaik, it's possible to update the gfx card's firmware to be powerpc compatible, then it should work... but probably won't work back in pegasos...?

bye, MarK.

Will be any support for the Radeon 9800 gfx card?

Hope so...

Here's to hoping that a release for the Powerbook G4 will show up soon. :)

In the initial release it doesn't even have to have powermanagment and laptop specific functions for me to buy it, as long as those bits show up later in an update. Right now I have an old Powerbook running at 1.33ghz with 1.5gb ram hooked up to an external monitor, usb mouse and keyboard running as a stationary. MorphOS would be really fun to play around with on that and as I understand it the troublesome bits are networking and the ADB bus?

> Will be any support for the Radeon 9800 gfx card?

AFAIK 2D is already supported since MorphOS 2.0.

Quote:

If needed, I guess the team could change the amount of RAM that they reserve for OS devices and such at a later date to make it match the 1.8gb free, or usable RAM that OS4.x does, unless they are currently using more that 0.2gb RAM for those devices and other such OS needs. Not that it is likely that any MorphOS program is going to need more than 1.5gb RAM, or if it does, is an additional 0.3gb going to help?

Maybe by that time, many years into the future, MorphOS will have developed a "work-around" to the memory limitation, or they will create some kind of "Extended Memory", or "Expanded Memory" similar to what was done for MS-DOS to go above the 640kb limit. (that is if MorphOS is still alive years from now and also if there are any developers writing programs for it that need more that the available 1.5gb RAM)

> unless they are currently using more that 0.2gb RAM for
> those devices and other such OS needs.

The difference between 2.0 GiB (= 2.15 GB) and 1.8 GB (= 1.68 GiB) is actually 0.35 GB (= 0.32 GiB).

> is an additional 0.3gb going to help?

The difference between 1.8 GB (= 1.68 GiB) and 1.5 GiB (= 1.61 GB) is actually 0.19 GB (= 0.18 GiB).

will this powermac model be supported by morphos?

Apple Power Macintosh G4/800 (Quicksilver 2002)
it has a radeon 7500.

i've got only 20hrs to act so pls let me know the answer asap:)

Quote:

I wasn't going to reply to your post above because I did not want to show my ignorance regarding the difference between GiB and GB, but the more I tried to make sense out of what you wrote, but more confused I seemed to get. Your mixing and comparing of GiB to GB's has thrown me for a loop.

Are you trying to tell me that AmigaOS4.x can access 1.8GB, not 1.8GiB and MorphOS2.4 can access 1.5GiB, not 1.5GB, so the net difference between what AmigaOS4.x can access and what MorphOS2.4 can access is only 0.19GB, or 0.18GiB, which is much less than the 0.3GB, or 0.3GiB that I was assuming in my post?