Beth Richard disassembling the last CD1200!

A great video and she fixed the hinge spring!

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"Art challenges technology. Technology inspires the art."
John Lasseter, Co-Founder of Pixar Animation Studios

@BigD

Thanks for sharing!!

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The Illusion of Choice | Am*ga

"We built it on 5 FPGAs... we designed them such that each one of these bigger blocks... were big enough to fit into one FPGA... and that's how we developed the Akiko."

To anyone today who says that FPGA is just emulation and not related to 'real' Amiga hardware - take that!

Great vid, shame it never got made, I must visit this museum at some point.

PS: just playing with the Ai app again got it to make a song
Verse 1:
Beth Richard, she's the queen
Of disassembling machines
With her steady hands and focused mind
She takes apart the CD1200, one piece at a time

Chorus:
Disassembling, disassembling
Watch her work, it's quite astounding
Disassembling, disassembling
Beth Richard, she's the one

Verse 2:
She starts with the outer casing
And carefully removes each piece
She knows just where to find the screws
And gently sets them all at ease

Chorus:
Disassembling, disassembling
Watch her work, it's quite astounding
Disassembling, disassembling
Beth Richard, she's the one

Bridge:
With a gentle touch and a keen eye
She takes apart the CD1200
Piece by piece, she lays them out
So we can all see how it's done

Chorus:
Disassembling, disassembling
Watch her work, it's quite astounding
Disassembling, disassembling
Beth Richard, she's the one

Last edited by amigang on 09-Dec-2022 at 11:27 AM.

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@BigD

Thanks BigD - what a great video.

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Sam

@bhabbott

It is quite simple, using an FPGA for developing HW that is yet to exist is something different than using it to "recreate","simulate" (aka "emulate") vintage HW.

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@Kronos

Quote:

Kronos wrote: @bhabbott It is quite simple, using an FPGA for developing HW that is yet to exist is something different than using it to "recreate","simulate" (aka "emulate") vintage HW.

How is it "something different"? It isn’t, it’s exactly the same.

For sake of argument - what if the "recreation" is implemented using *the exact same* verilog files that was originally used for prototyping on FPGA before "baking" to the ASIC that what is being "recreated"?

During lifespan of an architecture or even a specific chip, the "code" is changed many times already, also for ASIC - is the 68SEC000 just a hardware 68000 emulator in ASIC?

Last edited by kolla on 11-Dec-2022 at 01:28 AM.
Last edited by kolla on 11-Dec-2022 at 01:27 AM.

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B5D6A1D019D5D45BCC56F4782AC220D8B3E2A6CC

@BigD

Thanks for sharing the video.

How good would it be if whilst we still had such treasures of the Amiga Community alive like Dave Haynie and Beth Richards that the likes of AmigaKit, A-eon and iMica etc to work together to make the CD1200 become a reality? It would be nice to think that if such a collaboration were possible the Beth and Dave would get behind such an undertaking. I would buy CD1200 for my A1200 for sure.

I can hear the arguments from the against camp already.

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@kolla

Just because there is no clear line, does not mean there is no difference.


AFAIK there is no FPGA Amiga based on original sources they all did the same thing that was done for UAE 20 years earlier. Examine the behavior from the outside and then recreate it as close as possible from scratch.



No idea bout how the 68SEC000 was made or why it would matter.

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- We don't need good ideas, we haven't run out on bad ones yet
- blame Canada

@bhabbott

I don't think the Akiko is the best example. What was it, some CD logic, AUX, and chunky to planar added as an afterthought?

A few Amiga dedicated boards would have had FPGA. In the final product. Things like video cards.

I don't know how they produced AGA chips. If they used FPGA to design them. Or if the designs were too big for FPGA chips.

@Hypex

Quote:

Hypex wrote: @bhabbott I don't think the Akiko is the best example. What was it, some CD logic, AUX, and chunky to planar added as an afterthought? A few Amiga dedicated boards would have had FPGA. In the final product. Things like video cards. I don't know how they produced AGA chips. If they used FPGA to design them. Or if the designs were too big for FPGA chips.

Not the 'best' example? Akiko also had the essential parts of the CIA chips in it, so it was 'emulating' a large part of the Amiga's peripheral hardware (and not very well). I don't know what they used to produce the prototypes for the AGA chipset, but I wouldn't be surprised if that also involved FPGAs. I very much doubt they used the same technique that Jay Miner did when he produced the Lorraine prototype (on a dozen large wire-wrap boards stuffed with TTL logic chips).

One thing missing from Akiko's CIA emulation was the floppy drive control lines. So if you wanted to add a floppy drive to the CD32 you had to include two CIA chips, and disable the (partially) emulated ones in Akiko. That was too much for me, so I designed a circuit using a few standard TTL chips that added just enough to get a floppy drive working. This went on a daughterboard that connected to the motherboard via the Kickstart ROM and a few flying leads, fitting under the rf shield to leave the expansion bay clear. Then I cut a hole in the right side of the case and put the floppy drive in there. With this mod the CD32 became useful as a computer without adding the expense and bulk of an SX1.

That was back in 1996. If I was doing it today I would seriously consider using programmable logic. It could then be a more complete and accurate emulation of the CIA floppy functions - better than my 'real hardware' solution!

Last edited by bhabbott on 12-Dec-2022 at 06:33 PM.

@Kronos

Quote:

No idea bout how the 68SEC000 was made or why it would matter.

It doesn’t matter, that was half my point. The other half of my point was that 68SEC000 isn’t a 68000, so when used on Amiga, it must be emulating the 68000, right?

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B5D6A1D019D5D45BCC56F4782AC220D8B3E2A6CC

@bhabbott

Quote:

Not the 'best' example? Akiko also had the essential parts of the CIA chips in it, so it was 'emulating' a large part of the Amiga's peripheral hardware (and not very well). I don't know what they used to produce the prototypes for the AGA chipset, but I wouldn't be surprised if that also involved FPGAs. I very much doubt they used the same technique that Jay Miner did when he produced the Lorraine prototype (on a dozen large wire-wrap boards stuffed with TTL logic chips).

I would have thought Amiga sites would have mentioned that. Most of what I read online, BBoAh being one example, described it as being primary for chunky to planar conversion. Looks like Wikipedia has a more complete description, which is funny, as it tends to criticised as if it's for ignorant readers.

Quote:

One thing missing from Akiko's CIA emulation was the floppy drive control lines. So if you wanted to add a floppy drive to the CD32 you had to include two CIA chips, and disable the (partially) emulated ones in Akiko. That was too much for me, so I designed a circuit using a few standard TTL chips that added just enough to get a floppy drive working. This went on a daughterboard that connected to the motherboard via the Kickstart ROM and a few flying leads, fitting under the rf shield to leave the expansion bay clear. Then I cut a hole in the right side of the case and put the floppy drive in there. With this mod the CD32 became useful as a computer without adding the expense and bulk of an SX1.

I suppose the CD32 didn't need floppy lines because the CDROM replaced it. And wasn't designed to be used as a full computer. Seems you solved the floppy in a slightly extreme way. I hope the colour matched. What about HDD?

Quote:

That was back in 1996. If I was doing it today I would seriously consider using programmable logic. It could then be a more complete and accurate emulation of the CIA floppy functions - better than my 'real hardware' solution!

CPLD or FPGA?

@Hypex

Quote:

Hypex wrote: Most of what I read online, BBoAh being one example, described it as being primary for chunky to planar conversion. Looks like Wikipedia has a more complete description, which is funny, as it tends to criticised as if it's for ignorant readers.

You might be reading too much into those descriptions. C2P is the most notable part of Akiko because it is a useful new feature, whereas its other parts are just reproducing existing functionality and therefore perhaps not worth mentioning. That doesn't make them less important to the operation of the CD32.

Wikipedia gets criticized because anyone can contribute to it, but most often the criticism is invalid because all facts must be supported by cites and anybody can dispute the accuracy of an article. That makes it auto-correcting by consensus and more trustworthy than sites set up by self-proclaimed 'experts' - at least for subjects that people care enough about to maintain. Wikipedia is often the first place I go to because I can check the sources (which often have extra info that I need).

Quote:

I suppose the CD32 didn't need floppy lines because the CDROM replaced it. And wasn't designed to be used as a full computer.

Correct. It deliberately didn't have a floppy drive to keep costs down, and to make the emulation easier. The expansion port includes a line that can be activated to disable Akiko's CIA functions for adding real CIA chips. Fortunately that can be applied on a cycle by cycle basis, so I could just add the missing registers and leave the rest alone.


Quote:

Seems you solved the floppy in a slightly extreme way. I hope the colour matched.

Sadly no, I only had a beige floppy drive. However being on the side made it less visible, and who cares anyway?

Quote:

What about HDD?

That's when the SX-1 started to look attractive.

I didn't know much about Commodore's IDE implementation back then, and didn't care. Being able to boot from floppy was plenty enough for me. This gave us the ability to debug our CD32 titles in an environment almost identical to what the CD would run on, unlike my A1200 or worse the A3000.

Things like this were important when a 'gold disc' master cost NZ$1000 to make and had a turnaround time of several weeks. When I later got a CD writer I could put all kinds of stuff on a CD and use a bootable floppy disk to access it.

Quote:

CPLD or FPGA?

A CPLD would probably be enough - or perhaps a GAL or two combined with standard TTL chips, which is what I am tending towards today.

I have always been a fan of designs that use techniques any hobbyist can easily understand and reproduce with as few custom parts as possible. Since I and others have now cracked the GAL programming problem, and the chips are readily available and cheap both new and used, this is the direction my projects will likely be headed. It also makes the designs more in keeping with the retro spirit, as PALs and GALs were commonly used by manufacturers back in the day. For this reason I am also resisting using modern MCUs and modules, which might do a fine job but pull me away from Amiga development to other platforms I am less interested in spending time on.

Last edited by bhabbott on 16-Dec-2022 at 11:43 PM.
Last edited by bhabbott on 16-Dec-2022 at 11:42 PM.