Tuesday, October 6, 2015

MEGA65 prototype to be displayed at Amiga30 in Germany in a few days

Wondering what the MEGA65 might look like when finished?  

We don't know for sure ourselves, but our first physical prototype has now been assembled, and will appear at Amiga30 in Germany on the 10th of this month, and here is a sneak preview:


That's right -- the image above is NOT a C65 for sale on e-bay for 25.000 EUR or offered for swap for a small Greek island -- but a MEGA65 prototype.

The only original C65 part in it is the keyboard, because we are still designing our C65 compatible keyboards.  The idea is that the replacement keyboards will likely be identical in electrical function, so that if you happened to have one of your C65's with a broken key, you could use our keyboard to replace it.

The case is as close to the original C65 case as we could manage so far -- right down to the same problem with the right cursor key sticking due to very fine tolerances around that key. Naturally we will fix that as we iterate through to our final case design, which will also include several more adjustments to make it otherwise identical to the case design of the original C65's.

Inside is the Nexys4 FPGA board together with the first revision Peripheral Interface Controller (PIC, but not a PIC chip) that connects the real keyboard, joystick ports -- and soon C64 compatible cartridge/expansion port -- to the FPGA board.  In time, the PIC board will most likely be redesigned to be part of a single MEGA65 motherboard that will include the other ports as well as the FPGA and, hopefully, some RAM that isn't DDR.

The realisation of this prototype is one of the many great things that have been enabled by the partnership with MEGA, and which is making the project proceed much more quickly and with better results for everyone.

14 comments:

  1. Amazing progress - I can't get enough of the vibrant atmosphere these updates are jam packed with! ^_^ I suppose the prototype case has been 3D-printed? Oh, and about the keys and the char-ROM - would it be technically feasible to extend the PETSCII character map to include contempory characters such as the euro-sign (€), tilde (~) and any other glyphs people tend to rely on nowadays?

    ReplyDelete
    Replies
    1. Hello,
      In native mode (not yet implemented) it will be possible to use UNICODE and proportional fonts where required.
      Paul.

      Delete
  2. Nice one! What does "some RAM that isn't DDR" mean? I thought the DDR RAM of the FPGA board will be used for memory of the Mega65 (not counting the internal RAM of the FPGA itself or course), so I can't clearly see, what kind of RAM you wrote about. Thanks for the answer in advance :)

    ReplyDelete
    Replies
    1. We will still be supporting the DDR FPGA board, but DDR RAM is horrible to work with, so if possible I would like to have a simpler type of RAM that has lower latency.

      Delete
  3. " In time, the PIC board will most likely be redesigned to be part of a single MEGA65 motherboard that will include the other ports as well as the FPGA and, hopefully, some RAM that isn't DDR."

    What do you mean as a single MEGA65 motherboard? Are you saying in the future we will move away from Nexys4 FPGA board all together and actually have a real C65 motherboard with it's OWN FPGA and everything connected as a single motherboard and it will be big in size that fits snugly in this case??!

    Are you saying that the Nexys4 FPGA board is used only for prototypes and ones it passes the prototype phase you will make a custom FPGA Mega65 motherboard??

    ReplyDelete
  4. Whoa! It seems like this project progressed even more than i dared hope for. I really like what i see ;)

    I also really like the plans regarding a proper motherboard. But it would be wise to use a fpga sodimm as a 'cpu module' to make the system able to accept larger fpga's and softcores in the future.
    My guess is you also will be able to limit the main board itself to only 2 layers, making it cheaper and easier to manufacture.

    Artix-7 100T sodimm modules here:
    http://www.enclustra.com/en/products/fpga-modules/mars-ax3/

    ReplyDelete
    Replies
    1. Hello,
      Glad you like what we have achieved so far!

      As for the SODIMM module interface, this is potentially interesting, although the cost of the SODIMM modules is still rather high. I suspect that we can get something fabricated ourselves for the same price or less, and that would include all the other ports and things, so I am not really sure if the SODIMM is the best solution -- but we will keep it in mind.

      Paul.

      Delete
  5. Presentation? What presentation?

    ReplyDelete
    Replies
    1. The presentation described in this blog post :) As I was unfortunately on the other side of the world (a different side than the one on which I normally reside), I wasn't able to be there. However, I understand from what I have heard from the folks who made it there, that it went really well. I have only seen a couple of photos so far, and will likely make a new blog post when I get the full debrief.

      Paul.

      Delete
    2. Could you please make sure there is video to watch? I want to watch it in action please!

      Delete
    3. Hello,

      I am hoping that there is a video, too, as I wasn't there to watch it first-hand. What I do know, is that if there is a video, it will most likely be in German. I'll post when I have more of the material.

      Paul.

      Delete
    4. The only video that I have seen so far is this one (German): https://www.youtube.com/watch?v=nCyBoulxdj8

      Delete
    5. Quite right -- I have now made a short blog post with the video embedded.

      Delete