Re: daughter-board questions?

How big will the extra FPGA be - that is, how many gates?  And will there be enough space for future expansion once you have completed the new CPU implementation?

Re: daughter-board questions?

And wouldn't a 68040 be better than a 68060?  It's my understanding that the 68060 has a simplified instruction set, so some instructions are emulated - so I'd expect a 68040 implementation to run faster in the same FPGA.

Re: daughter-board questions?

Yes, it would be more like a super fast 68040 than a 68060 I guess.

Re: daughter-board questions?

Will the daughterboard be redundant when the core supports more and more functions and gets optimised ? Or to flip the question around: What is the advantage of a daughterboard that the mainboard cannot supply ?

I have been away from the forum for a while -- just curious on the whole daughterboard situation which seemed like a great add-on a few years ago when I got my first replay card smile

Re: daughter-board questions?

espskog: legacy ports?

Re: daughter-board questions?

More memory, USB ports, Ethernet port, fast 060 (or 040), expansion port, etc.

Re: daughter-board questions?

BTW what's the final configuration memory wise for the daughterboard? At some point you were talking about 128mb and eventually 256mb.

Re: daughter-board questions?

I'm trying to get 256MB on there, but it complicates layout somewhat.

Re: daughter-board questions?

is that dual channel then for twice the bandwidth?

Re: daughter-board questions?

Yes and no. I'm still looking at how we can extract the maximum bandwidth from the 68060, and leave it open for an FPGA module as well. It may be easier to do two daughterboard, one with an FPGA an one with the '060.

I'll finish this over the christmas holiday, the factory is waiting.

Re: daughter-board questions?

Two daughter boards is the way to go if someone really wants an 060.  Even an 100MHz 060 is no match for a big FPGA with a 64 bit mem path.  To me, the 060 is a waste.  It's a horrible CPU to deal with from a programming/capability standpoint.

62 (edited by cunnpole 2016-12-16 23:12:25)

Re: daughter-board questions?

It does at least get you a known cpu with known issues,  fpu and mmu. I agree fpga is the long term goal but that could be several years away. It would even be good to see the apollo core supported, but even that may never have a real mmu. Given that we've seen what the old daughter card can do with an 060 and we are so close to the new one I see no reason to stop now

Re: daughter-board questions?

I would prefer a db that can take a 060 for compatibility reasons and fpga for the future.
It doesn't matter if the 060 was crap or not, it's what's used. The replay should be all about compatibility if you ask me. It will never set a new standard in the Amiga scene. 99.9% of all new Amiga 060 releases are scene demos anyway. Ofcourse it would be cool with a new 100% compatible but super fast 060 built in the fpga but that will probably never become reality.

So if i had to make a choice, i'd take the 060 daughterboard but i would prefer a daughterboard that would let me see select real/fpga 060.

Re: daughter-board questions?

The daughterboard will let you use the softcore when needed for compatibility so that's perfect :-)

Re: daughter-board questions?

I would much rather see an 040 than an 060 on the daughter board, due to the 040 having much better compatibility.  There is a lot of stuff that will just never work on the 060.   The 060 and 040 *can* be pin compatible.  Phase5's 060 board could use an 040 with a simple jumper change (for the core voltage/clock speed).  THAT would be the IDEAL solution.  You could use a fast 040 chip and have max compatibility.  I have a 40MHz 040 in my A3000 with memory connected directly to it, and its blazing fast compared to a stock A4000 and I can of course run everything without having to figure out what works and what doesn't.

Re: daughter-board questions?

Yeah thats true that it could be interesting to have a 040 board for the reason you pointed Jim, but that could be done for a 2nd rev I guess? (Just to avoid more delay or maybe its not a big change for Mike?)

Also the over clocking for both cpu would be the same?

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No one codes for the 040... get over it. wink

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Plan is to allow clocking up to ~114MHz - apparently some rev6 will work this fast!

Re: daughter-board questions?

Right, x8 memory chips are quite hard to get hold off, however 512mb x16 are ok. I'm looking to clamshell mount these, which would allow 128MB / 256MB options (+ 64MB ram on the main card).
I think this should be ok for now?

Re: daughter-board questions?

sounds good, 256mb should be more than enough smile

Re: daughter-board questions?

Right, some more questions now the final design is taking shape. I'm still waiting for confirmation that we can get some of the parts, but so far so good.

The 68060 board has it's own power regulator for the CPU. This will allow the voltage to be changed by modifying a resistor. I'm looking at other options, but they are a bit more dangerous.  Looking at 3A-4A 3V3 for the CPU.

RTC is a go with supercap backup.

Additional SD card slot to allow directly connected mass storage. Normal size or micro SD preferred ? (May have to be micro to save space...)

Ethernet 100MB and USB2 host.

256MB memory.

I'm also looking at digitial audio out (toslink/spdif) and MIDI ports (for the Atari mainly).

I know Spot wanted audio in, but I haven't found a solution for this yet. Does anybody else?

Re: daughter-board questions?

Personnally I would say normal size for the sd card if possible as you can use micro with an adapter + they seems to be a bit more strong/reliable if you swap quite often (aka use as a mass storage), but that's not critical smile

midi port would be a great addition! Worst case scenario we could have tx/rx port and do it a la Mist?

Re: daughter-board questions?

SDCARD----*/
If you can keep standard sdcard that would be good yes im in for that. Yes most of mine are slotted in holder too.
Directly connected mass storage thats cool. (Note: If u need space for midi option, go the mini).
060-----*/
Im assuming that you are going with the idea that, you are going to leave the 060 socket blank so people can buy there own and slot it in when they wish, to make it cheaper if required for some?Two versions?Ie: For me, im happy for now with Ethernet and usbs and clock+ram etc. Were the 060`s going to be sold separately? i remember you said they are quite difficult to find for now.
MIDI----*/
Yes please as an option, so good for musos and /sampler/protrakker people. (Amiga/Atari)
AUDIO--*/
Audio in, this would be something yes if possible. Again only as an option.
yup, toslink/spdif.
USB-----*/
Still 3 usb ports? (There has been some pictures on the net of previous demo boards?)
ive attached a picture of the daughterboard i found on the net, no idea how old it was.
Does it look the final design anything like this one?

Mm only other things? how much will this sell for any idea compared to price of base/replay board?
And, What will the height be aprox with this clamped to the base, just thinking of a case size?

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Re: daughter-board questions?

The board to board stacking height is 3/4 inch (19.1 mm). The total height including the top connectors fits in the ATX IO window.

Re: daughter-board questions?

Ah excellent, then still fit in any mini case.:)