I think this is my first post to this forum site. I just received notice that my "First Contact" X1000 is ready for shipping to me, in an email from AmigaKit earlier today, so I am excited that I will finally be getting my first OS4 compatible computer when it arrives. (Just have to send in the balance of the money for it after I sell one of my kidney's ;-) )
I was wondering about possibilities for the future of OS4 running existing Amiga 68k coded programs and games that depend on the original custom chipset hardware. We have seen the success and increasing performance of several different FPGA based computer systems in their ability to run most, if not all Amiga software from the past, so it is a well proven method for providing backward compatibility. I know that the X1000's powerful PA6T CPU should be able to provide an acceptable performance at running E-UAE, but my question is this; is it possible, or even desirable to explore the possibility of creating a MiniMig on a PCI card to provide seamless integration of OCS, ECS & AGA compatibility from OS4 without the need of Petunia emulation/translation? Or, is it just better to stick with what we already have and continue to improve Petunia and Run-In-UAE with E-UAE?
I know that the ultimate goal is to have better and more native PPC OS4 applications and games, but many of us old time Amiga users will also always want to be able to run many of the old Amiga 68k OCS, ECS & AGA programs and games, for nostalgic reasons.
Another thing I would love to see would be an adapter and supporting drivers and code that would allow me to install my Video Toaster & Flyer cards into my X1000, but that is highly unlikely and a new HD video editing suite for OS4 would be a better solution. Still, giving any NG Amiga more options to completely replace all features that the original Amiga's gave us is a good thing in my eyes, as long as providing that backward compatibility does not hinder progress, or new features in OS4. Not many people still use their old analog video camcorders like I do. I'll just have to keep my A4000 beside my new X1000 (can't wait for the X1000 to arrive).
@AmigaDave
Imho you choice wrong site for such kind of threads. That site about coding, not about general stuff, which can be discussed on aw/amigans with better success and more feadback from users.
I've thought about this myself. The Amiga on a PCI card idea. Personally I thought this would have benefited the original AmigaOne as well. Being that the A1 was meant to be a PPC board you plug into an A1200. I still would have liked that idea to come to fruition and utilise the AGA chipset on the A1200 while being able to use it as a keyboard. So we still had a real Amiga keyboard.
The closest we seemed to have was the Catweazle. An Amiga style floppy controller on a PCI card. That also lacked proper OS4 drivers just to make matters worse!
To do such a thing though OS4 would need to reserve the chipset memory located in the lower 24-bit address space. And then map that area into the PCI space with the hardware register addresses. Location 0 and 4 would be hard to manage though as 0 is illegal to touch (NULL pointers) and 4 is used for ExecBase. As long as those are kept away from it should be fine. And really only CIA and the $DFF000 register should be touched.
Now there is chipset access doesn't mean that all games would work, if the code ran under OS4 for example. Some "OS friendly" games did some bad hacks into the OS. And hardware bangers take over the machine. Most likely it would be best to run the code on the PCI card by whatever means or even in a custom emulator on OS4. Like a UAE that only emulated the 68K and let the memory access passthrough.
As to Video/Zorro card support, yes that would be nice, but would require some kind of hardware dongle that would fit in the machine/tower case. As well as compatible software for reasons discussed above. I guess it would be a kind of reverse Mediator: Zorro slots for a PCI Amiga! :-D
@kas1e,
Sorry you think this is not the place for this discussion. It is under Misc. in the OS4 Developer's Corner, and I think that ONLY OS4 developers can accurately answer this question if the idea of a "MiniMig" like device on a PCI card is even possible. Answers on those other sites you suggested would be mostly a waste of time and full of opinions from people that have no working knowledge of OS4.
@hypex,
Thanks for your informative reply. I understand the problems you are describing with memory allocation conflicts and wonder if a duplicate memory space could be created for running 68k Amiga games and applications in that would be separated from the rest of the OS4 memory space and thus "get around" the problems you described? It may be more work than it is worth, but I am just throwing out ideas and suggestions. Perhaps all of this has already been thought of many times before and discounted as not possible, or not able to provide satisfactory results for the effort required to make it a reality.
My thoughts are that now that the X1000 is publicly available for purchase and will soon be in many users hands, with it's second core and increased performance far above and beyond any previously available AmigaOne, maybe some things that were not feasible in the past have become worth re-evaluating a second time, as they may be possible now on the X1000?
Thanks again for your responses. I have tons to learn.
Edit: @hypex, Yes, a reverse Mediator board is exactly what I would be interested in. I know it is a crazy idea, but there are still tons of useful things that can be done with certain Zorro cards and Video Slot cards and it would be fantastic if some crazy Amiga hardware guy produced such an adapter for a PCI slot or the Xena/Xorro slot. Much better to be able to run and use one AmigaOne X1000 computer instead of it plus an A4000 sitting next to it.
Creating any sort of "Reversed Mediator" Bridgeboard from PCI or PCIe slots and allowing
for Zorro2 or Zorro3 devices to be plugged in is actually going to involve some serious
contortion of the logic and lines.
anything short of slaving a Classic Amiga as this "bridgeboard" using some kind of CPUslot
cabling setup connecting to a Bridge Card Controller board would still have issues.
as you would effectively need to create a chipset equivalent to the original Buster.
You would also walk into a "Bus contention" bottlenecking the PCI host system,
in addition to the number of IO lines (96 pins with 4 n/c lines? from memmory)
even allowing for local management of which card has priority,
a "greedy" Zorro card would be able to suck the life out of the system.
so while such a device for old cards to be used is plausible... would it be effective?
I would promote that any such idea as this be explored with caution.
@Belxjander,
Of course exploring any expansion ideas must be done with caution, but discussing the feasibility on a forum site should be safe enough.
I really doubt that any kind of reverse Mediator board could (or would) ever be built, even if it is possible. There are very few Zorro boards that are relevant any longer, as most can be easily replaced with better alternatives. The only boards that I feel can't easily be replaced are the excellent Video Editing gear like the Video Toaster/Flyer and V-Lab Motion and both of those are only for analog video input, which is a dead standard, except for dinosaurs like me that persist in using old gear. (mostly because it is expensive to upgrade everything). Even I will soon abandon all analog video gear and move to digital, where there are many software only solutions for editing.
The Custom Amiga chipset on a PCI or Xorro card is a more feasible project to discuss.
Some things to think about...
How much does Run in UAE cost?
How much does a custom designed FPGA card for this task cost?
How do you get both Radeon and FPGA graphics to monitor?
How do you get both SB600or PCI audio and FPGA audio to speakers?
How do you get the huge toaster card to physically fit comfortably and securely in a case with all this stuff?
If Video slot/Zorro expansion cards are what you want to use, then use a Classic. Plugging them into an X1000 won't be practical, it would be a hideous hack. Yes, Amiga fans have a tendency to do hideous hacks, so maybe someone will. But, yuck.
If it's classic software you want, without related hardware, use UAE. It should run fine on X1000, and cost way less than an FPGA with a bunch of audio, graphics, etc. muxing circuitry and connectors. The FPGA would eat money, and it's not clear what the benefit to pure classic software would be, if any benefit at all. But FPGA is you're only path to Zorro/video slot if you must have them. (Maybe Xmos, but same ugly how does it all fit hack) I wanted Zorro for BoXeR, and I think it made sense back then. This is now, and I no longer think that including Zorro or Video slot on NG Amiga board is particularly useful. Things have moved pretty well to PCI cards or software. Now we're stepping toward PCI-Express cards. What Zorro or video slot card doesn't have a PCI/PCIe or software replacement today? (Yes, we may lack port of software or driver for them, but what doesn't exist at all even if not on AmigaOS?)
I'm saying this as someone who wants to add Zorro/video slot to Minimig... Makes some sense there, but I want to learn Verilog and that is interesting way to do it. I don't think it's practical other than education how to do it. Certainly not practical for NG boards.
The only way I can see anything like this working would be using an A2000/A3000 or A4000 Classic
and replacing the CPU card with a PCI/PCIe based "replicator" card that slotted into the NG
hardware expansion bus providing a full backwards compat bus controller along with the rest of
the classic chipset and everything except software really...
Run-In-UAE or the current Petunia would then need some optional library to use the classic
hardware when it is attached, and this in itself is still a frankenstein monster hack
Binding an entire classic system as an NG system expansion.
Would this even be feasible?
what about running a Classic machine side by side with a new machine with a Video Capture
setup on the NG system? less hassle?
a minimal Classic system in good condition can provide a video feed for an NG system to
Digitally capture right? ... or does this not work?
@AmigaDave
The memory problem may be the easiest to get around actually. Since OS4 already virtualises the memory in the system. And the 2GB that makes up the memory map mapped from physical to virtual.
In fact, OS4 already includes basic CIA mouse button emulation. And the custom chip area is usable for emulators installing a trap handler to catch "illegal" hits on those areas. So the best thing here would be to map custom chip virtual to AGA PCI space physical.
Using the second core of the X1000 would be a good idea. But right now OS4 doesn't support it so even on the X1000 OS4 is still a 32-bit single core OS running on a dual core 64-bit CPU. :-)
Linux does but we want to stay in Amiga. I can see the need for real Amiga video cards and associated software. But I wonder could these be simulated in software, that is as a virtual entry added to expansion library (like UAE) that would redirect to actual video hardware on board.
With external AGA, as spoke of, sound and video would need to be merged with the sound and video in the system. Using a CD audio input for sound would be easy. But it should be mixed in with the system sound I think except AHI doesn't support hardware mixing so that would go against the point. And video should use an overlay mode so the video card does the e work of merging it with the display.
Just my thoughts. :-)