Introducing the N2630 CPU Card

[jasonsbeer]

I am pleased to announce the N2630 CPU card for the Amiga 2000 family of computers. The N2630 is completely open source and can be built by anyone for non-commercial purposes.

The N2630 is a 50MHz Motorolla 68030 CPU card with additional RAM and IDE device port for the Amiga 2000 family of computers. It is installed in the CPU slot where it immediately upgrades the system to a 68030 processor with FPU, up to 264 megabytes of Fast RAM, and an IDE port. The N2630 is intended to be an evolution of the A2630 card.

Features

1. Motorola 68030 microprocessor running at 50MHz.
2. Motorola 68882 math coprocessor running up to 50MHz.
3. 4 or 8 megabytes of Zorro 2 Fast RAM.
4. 16 to 256 megabytes of Zorro 3 Fast RAM.
5. IDE port with 40-pin cable and CF card options.

Find the project on GitHub: https://github.com/jasonsbeer/Amiga-N2630

[tygre]

Awesome!

[giantclam]

Great work m8, good to see the IDE/CF card support ...what are your plans (if any =) for the reserved P90x jumpers?...ie; SCSI perhaps? [makes me wish I hadn't sold my A2000 machines long ago =^]

[Magic]

That's amazing! Thank you for all of those hours of work.

[eXeler0]

Wow, that is simply awesome.

[Reynolds]

This is amazing. Especially because of the CF card slot. How much does it cost? Haven't seen it mentioned but I think this is an upgrade which definitely worths every penny.

BTW I was wondering how difficult would be a ZII/ZIII PCMCIA card slot...? Just because of the PCMCIA network cards for big boxed Amigas. Nowadays I feel it more and more difficult to find a Zorro netvork card.

[alexh]

Great work. I am sure this will be interesting to a lot of people. I think the only other A2000 68030 product available today is the TF536 with a CPU slot adapter card? Oh and perhaps PiStorm if that counts?

A clock-port would have been an interesting addition. Maybe put that down as an enhancement if you have any spare pins?

Why did you call it "Zorro 3 Fast RAM"? Is it because it is mapped into the Zorro 3 address space? You're not the only accelerator designer to do that, I think the TF cards also do that. Is that because the normal 32-bit address space for accelerator memory is only 128MBytes?

Originally Posted by Reynolds

BTW I was wondering how difficult would be a ZII/ZIII PCMCIA card slot...?

I don't think this is possible. If you wanted to use the A1200/A600 drivers for PCMCIA cards you'd have to mimic the Gayle registers for PCMCIA and that address space is not available in the ZII/ZIII region. It would only be practical as part of an accelerator (which has access to the whole address space)

Originally Posted by Reynolds

Nowadays I feel it more and more difficult to find a Zorro network card.

They are in stock at most resellers.

https://icomp.de/shop-icomp/en/shop/...-surf-100.html

https://amigakit.amiga.store/surf-zo...vof0v4j3o6gauf

[jasonsbeer]

Thanks for the comments, everyone. Much appreciated!

Originally Posted by giantclam

Great work m8, good to see the IDE/CF card support ...what are your plans (if any =) for the reserved P90x jumpers?

The plan was/is to use those to set PIO mode options or even future unknown possibilities.

Originally Posted by alexh

A clock-port would have been an interesting addition. Maybe put that down as an enhancement if you have any spare pins?

It can be done. My personal bias is to see devices made for the Zorro 2 bus. It's far more capable than the clock port.

Originally Posted by alexh

Why did you call it "Zorro 3 Fast RAM"? Is it because it is mapped into the Zorro 3 address space?

Yes. That RAM resides in the 32 bit address space of the 030 and is AUTOCONFIGed as a Zorro 3 device.

Originally Posted by alexh

You're not the only accelerator designer to do that, I think the TF cards also do that. Is that because the normal 32-bit address space for accelerator memory is only 128MBytes?

The Zorro 3 spec indicates it will support up to 4(?) AUTOCONFIG cards up to 1GB each. That's from memory, which can be faulty sometimes. The 68030 will support many gigabytes of addressable memory, but the Amiga uses the top few addresses for AUTOCONFIG addresses.

Originally Posted by alexh

I don't think this is possible. If you wanted to use the A1200/A600 drivers for PCMCIA cards you'd have to mimic the Gayle registers for PCMCIA and that address space is not available in the ZII/ZIII region. It would only be practical as part of an accelerator (which has access to the whole address space)

Gayle is not an AUTOCONFIG device, so the Gayle registers exist outside the Z2/Z3 AUTOCONFIG space. Rather, Gayle is addressed directly by Amiga OS in the 24 bit address space of the 68000. I think a Gayle CC could be done, but I am not aware of any efforts to replicate it. The N2630, like many others, uses the Gayle IDE controller registers.

[jasonsbeer]

Originally Posted by Reynolds

How much does it cost?

Quick estimate is ~$150-200 US each. This really depends on where you get your parts and what the current pricing/availability is.

The common logic and passives are around $50-$60 total.
The boards are going to be around $30 each with ENIG finish (you must buy 5).
The 68030 and 68882 are going to be from $25 - $40 each.

The Xilinx CPLD's are the big wildcard right now. I have been getting them from AliExpress...no other choice. I found a good supplier and am paying approximately $6 each, but you have to buy 5 or 10, depending on the part.

As always, these projects are best if you go in with some friends to build multiple copies.

[QuikSanz]

Hmm, has the FPU that TF does not have but does it have DMA?

[SpeedGeek]

Good work! Having an accelerator card which actually plugs into the A2000 CPU slot is very nice... and one that improves on the A2630 is very cool too.

If I had not done so much work hacking and overclocking my A2630, well that's another long story.

P.S.
My last A2630 speed-up hack (which might help with your next firmware release) is located here:

https://eab.abime.net/showthread.php?p=1523692

[jasonsbeer]

Originally Posted by QuikSanz

Hmm, has the FPU that TF does not have but does it have DMA?

DMA is confirmed working with the A2091 SCSI controller. Which happens to be the only DMA device I have.

[jasonsbeer]

Originally Posted by SpeedGeek

P.S.
My last A2630 speed-up hack (which might help with your next firmware release) is located here:

https://eab.abime.net/showthread.php?p=1523692

Thanks, I'll check it out. You are right. The E cycle is original to the MC6800 and SLOW. The best there was in 1974. Maybe? I count 54 waits at 50MHz during 6800 cycles.

FYI...Here is the MC6800 state machine timing diagram for the N2630.

https://raw.githubusercontent.com/ja...INE%20READ.png

[patrik]

@jasonbeer: on your github it says that fast ram is not available in 68000 mode. Would it be possible to make the Zorro2 fast ram available in 68000 mode, like the original A2630?

[SpeedGeek]

Originally Posted by patrik

@jasonbeer: on your github it says that fast ram is not available in 68000 mode. Would it be possible to make the Zorro2 fast ram available in 68000 mode, like the original A2630?

Your information source is in error. The original A2630 does NOT make the on-board Fast RAM available in 68000 mode.

[QuikSanz]

My old G-Force 030/40 GVP CPU Control shuts down all fast ram.

[jasonsbeer]

Originally Posted by patrik

Would it be possible to make the Zorro2 fast ram available in 68000 mode

I will be attempting that in a future firmware revision. I wired the N2630 with that intent, but it needs to be implemented.

[patrik]

Originally Posted by jasonsbeer

I will be attempting that in a future firmware revision. I wired the N2630 with that intent, but it needs to be implemented.

Awesome!

Another followup question to the 68000 mode: would it be possible to allow the IDE port to work in 68000 mode? Reason for asking is that it would make it super convenient to use in 68000 mode as it would still have access to the harddrive.

[S0ulA55a551n]

Originally Posted by QuikSanz

Hmm, has the FPU that TF does not have but does it have DMA?

Isnt that the problem with PIStrom on A2000, no DMA?

[jasonsbeer]

Originally Posted by patrik

would it be possible to allow the IDE port to work in 68000 mode? Reason for asking is that it would make it super convenient to use in 68000 mode as it would still have access to the harddrive.

Its not possible in the current hardware configuration, but could be done with a hardware revision. It would be necessary to mux the IDE data between the 68030 and 68000 busses. I considered this at one time, but elected to leave out that additional hardware in favor of getting the initial release running.

After thought...missing the obvious...the muxing hardware already exists. I would have to investigate if the existing hardware could also be leveraged with the IDE. The needed signalling may not all be there.