Minimig PCB run - interest thread

[Dennis]

May I give some suggestions?
If you do a new board design please change the following from the orginal design:

1) Use a single chip ram like this one, available at digikey for example.
2) Include a +5V regulator on board OR use an ATX-style powerplug if you go Mini-ITX. The +5V regulator should be capable of providing about 1A to safely power all peripherals one might attach.
3) Hardwire the patch needed to get the current board to run. Alternatively, you can also swap pin81 and pin 79 on the FPGA. This way you still have four user-IO's left. You do need to change the .UCF file though and recompile the core.
4) The MMC card interface has a resistor based clock gate circuit around R50,R51. This should be replaced with a proper (single) gate "OR" chip. The margins on this signal are pretty tight on the current board. Also, R49 should be 0 ohm ideally to avoid problems when upgrading the PIC to a newer PIC18LF2620 or something similair. Margins are tight on that signal too atm.

And you could do the following optional improvements:

5) You could consider using a single 20MHz oscillator and figure out how to program the DCM to generator the proper clocks, this would spare a crystal.

Have fun!

PS Offcourse I would like one too!  :-)

[Fester]

I'd like an original design fully assembled PCB.

(I'm also fine with the mini-ITX size if that's the resulting choice)

[Blinx123]

I think about ordering one but then it would be fun to build one myself.

BTW: What I would prefer over this both options would be an original board created by Dennis himself if this is somehow possible:)

[freqmax]

Belial6 wrote:
I'm kind of a fan of the ribbon cables.  It would make custom cases easier to make.  I would expect that we will see lots of  custom cases for the mini-mig.  With how small the board is, I would think that it would be trivial to make an adapter plate for anyone wanting to mount the mini-mig in a mini-atx case.  Personally, I would like to put the mini-mig into an old gutted laptop.

Maybe there is a standard for those 9pin RS232 serial connector brackets often found on pcs? ..would be really neat to be able to just plug in :-)

As for adapter any plate with a 11x11 cm square hole should allow mounting in MiniATX, problem solved. It's not problem making that hole fit a 3.5" (10,2 x 14,7 cm) either.

Is there any standard formfactor of laptop interiors?
Maybe you could just rewire the digital RGB before the resistor A/D and vsync/hsync to the builtin TFT, and let some D/A port on the MCU control the brightness and similar ..?

[Ohno]

I'd like a fully assembled one.
I also prefer using standards. So I vote for Mini-ITX.

[Crumb]

/me bows to Dennis, the custom chip master :-)

[Mikkel]

I'm interested in two to four unpopulated boards.

It would also be nice if you could sell components, as the parts are much cheaper if bought in bulk.

Having headers on the board instead of the connectors is a good idea, but I don't like the idea of the mini-ITX form factor. Headers would not take up much more space than the original connectors, probably even less, so it should still be possible to make it 12x12. 17x17 is just over twice as large, or twice as large as it needs to be in other words. Also, I suspect the boards might get much more expensive if they were made for the mini-ITX form factor, seeing as how you usually pay for the area when you order circuit boards. Having it fit in cabinets made for mini-ITX would be practical, but think of the drawbacks, much more expensive boards, and harder to mount them in smaller cases. At 12x12 they could probably still be mounted in mini-ITX cases without too much trouble, and they will also fit in nano-ITX cases.

Anders M.

[kolla]

Two assembled ones for me :-)

I really dont see the point of using mini-ITX form factor at this point - people who insist can mount it on a mini-ITX sized card board or something (sheesh!)

The smaller the better is my like, and as someone else here suggested, it might be interesting to build it into for example an original A600 casing. Uhm.. is there a way to connect original A1200/A600 keyboards? :-)

[AltRN8]

I am interested in one and it doesn't matter if its prepopulated board or not.

[amigadave]

Two for me, the smaller the better is my preference too.

I hope people don't gut working A600's and A1200's to put a Minimig inside???

Will the proposed PCB run incorporate the changes/upgrades that Dennis has suggested?  I hope so.

Thanks for starting this thread.

[arkpandora]

Whatever the Minimig is (no I didn't read the whole threads but yes I have a vague idea), I am interested if

1. It can do at least what a basic A500 does (no doubt about that obviously) ;
2. There's no soldering to do ;
3. You can supply it with power and install it in a standard PC case.

If the PCB is plug-and-play - already installed in a case - it is even better.

Edit : Of course please don't sacrifice any working Amiga - or I'm not interested anymore !

Good luck !

[TrevorDick]

I want an assembled PCB.

Me too!

TrevorDick

[persia]

12 x 12 would be ideal, all it really needs is about 6 USB ports and a video port or some kind, composite would be nice, then yo could plug it into an iPod like device (Cowon, Archos) hookup a projected keyboard and you could carry the whole thing in an winter jacket pocket!

[Plaz]

As much as I love custom hardware, I think the standard mini itx layout with Dennis' suggested design impovements would be best in the long run. That way you can use comercial cases or build your own design with only one run.

Mini ITX would be my choice.

Plaz

[narmi]

I thought about this for a bit, and have decided that I like the 12x12 board size better.  I'd prefer to buy a board with some improvments made, the improvements suggested by Dennis, as well as pin headers for the serial port and joystick ports.  The video, power, kb, and mouse ports should probably be on board at the back (short wires = less noise).

Would it be possible for the final schematic to be posted if and when the big order is placed?  If some of us wants more boards in the future we can have them made by Futurlec or some similar company.

EDIT: forgot to mention, that having a SO-DIMM socket (or similar) in place of the onboard ram would be awesome.  I know I've got a 32MB SO-DIMM around here somewhere.

[Evillord68]

I´ll take one fully assembled.