TG68 - The Open Source Minimig CPU into the FPGA

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Bravo! 3000 lines too, I'm impressed.

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billt wrote:

That's not a problem since you can use a splitter. My laptop just has one PS2 port but I can use simultaneously both keyboard&mouse.

I didn't know PS/2 ports could do that. Cool.

There are other cool things you can do with PS2's.  I have a PS/2 all-in-one keyboard that has a touchpad mouse incorporated with it (those who saw me at AmiWest a few years back saw me with it).  All runs down a single PS/2 line into the system.

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tonyyeb wrote:

alexh wrote:
If you have a MiniMig v1.x board you dont care.

If are a potential MiniMig v1.x owner, but cannot find one cos no one makes them, and were considering getting buying one of the slightly expensive off the shelf Altera DE1 or DE2 boards then you are wetting your pants as a more compatible DEx-MiniMig is on it's way.

So what will be the future? I buy a dev board and then i can download new code and use Amiga software on it?

Right

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amigadave wrote:
@freqmax,

I liked your first suggestion much better, and for an A1200 like Minimig, the 32mb RAM should be plenty.  I am sure it is going to take a huge amount of developing effort to get from v1.1 OCS to v3.x AGA w/68020+ soft CPU.  Perhaps as much, or more than Dennis had to put into the whole of his design?  It would be great if a small team of programmers would take it on and speed its completion.  A Minimig that is equivalent to an 030/50mHz A1200 in a small form factor and at a cost of $300 to $450 would be quite an accomplishment.

The FPGA you'd need to fit the 68020 + AGA would run you approx $300 on it's own.  Add in the other parts, you'd likely be nearing $1000.

Give it a few years.  We need to hit ECS before we go AGA, and by that time, prices/density should have come down.  Heck, the chip density used in MiniMig 1.0 would have cost almost $1000 not even 3 years ago IIRC.

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Cymric wrote:
From the looks of the software-68000, it shouldn't be much work nor take much extra gates adding the instructions and abilities of a plain 68030 given that almost nothing changed in the register model save for the addition of proper support for longwords.

Not singling you out specifically, but this has a bit in it that is driving me a bit nutty.  A lot of people keep calling this a software CPU.  No, it's an HDL CPU, that is it's a description of hardware.  While it can be run as software, it's end goal is to be hardware.  So please, let's just call it the TG68000?

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One thing I was pondering was in rolling this into a spare FPGA I have, and pairing it next to an original 60000, to duplicate instructions and see what differences there are.  Just need to find a minimalistic motherboard design for the 68k, like the old Altair, so I can directly manipulate them.

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AJCopland wrote:

downix wrote:
One thing I was pondering was in rolling this into a spare FPGA I have, and pairing it next to an original 60000, to duplicate instructions and see what differences there are.  Just need to find a minimalistic motherboard design for the 68k, like the old Altair, so I can directly manipulate them.

Didn't see this before.

Have you tried doing this?

Andy

Not yet, I cannot find any good documentation on how the front panel was programmed, so I'm having to recreate it by hand.  

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freqmax wrote:
What do you mean by frontpanel..?
Can't you use the FPGA to manipulate the m68k ..?

And manipulate it, how, without a keyboard, mouse, or other method of input?

I am trying to mimick the "front-panel" input from the first PC, the Altair:

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Ok, pt the resized one up, btw that free image host of yours stinks, useless for posting pictures into sites.  So I put it on one of my own sites.

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AJCopland wrote:

MiniMorph wrote:
I have just ordered 5 Altera DE1 boards from Taiwan.

I will sell a couple of them on in the UK if there is interest. I could sell them privately or on Ebay.

I could probably do the mouse keyboard mod on the boards and I will see if I can get some y cables as well. I will need then anyway.

Good news for my boot loader too. My development boards for that arrived today. I can actually run some code now !

Good to hear that your project is coming along, will you be sharing the re-design as you go or just at the end once you've worked all of the kinks out? I'm just getting to grips with gEDA (never used schematic software before) and trying to get everything setup correctly with the minimig sym files etc then trying things out in baby steps.

On a side note, damn this stuff is complicated when you're newbie, does anyone know of any good introductory guides!?! I've got it mostly installed and setup on Ubuntu, got the custom sym files from Dennis' site loading in ok and seemt o have teh schemtic loading with all of the components but an actual guide to using gEDAs gschema tool would be nice.

Andy

I've been having an issue getting gEDA to read the gerber files myself.