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Amiga computer related discussion => General chat about Amiga topics => Topic started by: straycat on February 10, 2008, 05:06:19 PM

Title: Minimig released for real!
Post by: straycat on February 10, 2008, 05:06:19 PM
According to the website today the Minimig has been released!

http://www.acube-systems.biz/eng/index.php

Title: Re: Minimig released for real!
Post by: Krusher on February 10, 2008, 05:09:20 PM
Someone made a booboo and released the info a day early  :-D
Title: Re: Minimig released for real!
Post by: IslDreamer on February 10, 2008, 05:47:15 PM
Please pardon my ignorance, but I just returned to the Amiga scene a couple of weeks ago.  What exactly does the Minimig offer? What OS and software can be run on it?  What kind of case would it fit in? :-?
Title: Re: Minimig released for real!
Post by: Jiffy on February 10, 2008, 05:51:29 PM
Check this (http://en.wikipedia.org/wiki/Minimig).
Title: Re: Minimig released for real!
Post by: IslDreamer on February 10, 2008, 06:20:28 PM
That helped, but it's still a bit too technical for me.

Will this run OS4 Classic?  If it's emulating an A500, is it powerful enough to run the newer OS? And how would you use older disk-based software?  
Title: Re: Minimig released for real!
Post by: WotTheFook on February 10, 2008, 06:38:34 PM
No, it just is a reverse engineered vanilla OCS A500.
Title: Re: Minimig released for real!
Post by: redrumloa on February 10, 2008, 06:39:27 PM
Quote

IslDreamer wrote:
That helped, but it's still a bit too technical for me.

Will this run OS4 Classic?  If it's emulating an A500, is it powerful enough to run the newer OS? And how would you use older disk-based software?  


No OS4, that requires a PowerPC accelerator. Think of the minimig as nothing more than a really small and flexible Amiga 500, nothing more, nothing less. Games are played from a MMC flash card, using disk images (.adf). Many older games have been released into the public domain as ADF. If you own an original floppy, it will not work on the minimig. However finding a backup in ADF form online is quite easy.
Title: Re: Minimig released for real!
Post by: Darrin on February 10, 2008, 07:01:06 PM
Shame there's nobody in the USA selling them.  I've emailed Acube to see about ordering one.

Actually, I emailed them last earlier this month for a price and git a replt and then emailed them again to ask about cases and how to pay and got nothing but silence.  I've emailed yet again and hopefully I'll get a reply...
Title: Re: Minimig released for real!
Post by: IslDreamer on February 10, 2008, 07:02:45 PM
Thanks guys, that is very helpful.

So what's the advantage of something like this vs. running classic games and software in an emulated environment like WinUAE/AmigaForever? At least in the latter, you can emulate much higher-end machines.

I guess I fall into the camp that really appreciates and looks forward to running the classic machines (I just bought an A4000D a couple of weeks ago), but I expect any new hardware to help move the platform into the 21st century. (If only the warring companies controlling its future would get out of the way).
Title: Re: Minimig released for real!
Post by: HenryCase on February 10, 2008, 07:30:46 PM
Quote
IslDreamer wrote:
So what's the advantage of something like this vs. running classic games and software in an emulated environment like WinUAE/AmigaForever?


Geeky coolness of the hardware, and encouraging future commercial Minimig development. Also, not really an advantage but, the Minimig can be expanded to emulate other computer and consoles systems (especially those based on 68k processors, lots of systems with this processor).
Title: Re: Minimig released for real!
Post by: Andeda on February 10, 2008, 07:38:35 PM
How many of you are going to buy one from acube?
Title: Re: Minimig released for real!
Post by: MaDDuck on February 10, 2008, 07:39:56 PM
Ahhhh....

But the million dollar question:

While running an interlaced screen outputting to the VGA port, can we still get the eyeball-itching interlace flicker???

and can a HDD be added to make it runnable as an Amiga instead of just an .adf player?



Title: Re: Minimig released for real!
Post by: Krusher on February 10, 2008, 07:44:41 PM
The Minimig has an onboard Flicker Fixer / Scandoubler

There's no IDE port yet so no, you can't hookup a harddrive.
Title: Re: Minimig released for real!
Post by: MaDDuck on February 10, 2008, 07:52:35 PM
Quote

Krusher wrote:
The Minimig has an onboard Flicker Fixer / Scandoubler

There's no IDE port yet so no, you can't hookup a harddrive.


awesome!!
So the flicker will still be there then?

oh well....
Title: Re: Minimig released for real!
Post by: Krusher on February 10, 2008, 07:58:20 PM
Quote

MaDDuck wrote:
Quote

Krusher wrote:
The Minimig has an onboard Flicker Fixer / Scandoubler

There's no IDE port yet so no, you can't hookup a harddrive.


awesome!!
So the flicker will still be there then?

oh well....


Actually, no flicker since Minimig has an Amber implementation.  
Title: Re: Minimig released for real!
Post by: MaDDuck on February 10, 2008, 08:00:47 PM
Really?

sounds impressive, I wasn't aware that could be done and still maintain 100% compatibility.

Hmmmmmmm
Title: Re: Minimig released for real!
Post by: Krusher on February 10, 2008, 08:03:16 PM
That's the beauty of FPGA, you can add certain features without breaking compatibility.

btw: Minimig is NOT 100% compatible. Yet. There are a few things broken, however most things work.
Title: Re: Minimig released for real!
Post by: Akiko on February 10, 2008, 08:11:39 PM

So some Amiga dreams do come true :-)
Title: topic skew
Post by: weirdami on February 10, 2008, 08:26:52 PM
Okay, I'm confused again. I now that Dennis did the MiniMig all on his own an it's all GPLed or something. What happened to the hardware that AI announced not too long ago that some non-Dennis was working on that AI was promoting as official or something? Not the AmigaOne. Wasn't there something else? Where did all that go?
Title: Re: topic skew
Post by: cv643d on February 10, 2008, 08:34:20 PM
I think Im going to get one in the comming months even though I have six A500 in the closet.
Title: Re: topic skew
Post by: weirdami on February 10, 2008, 08:41:02 PM
@cv643d

Six MM's will take up less space in your closet.

So will six M&M's, for that matter. Both, incidentally, don't melt in your hand.
Title: Re: topic skew
Post by: AndrewBell on February 10, 2008, 09:06:00 PM
Quote

weirdami wrote:
What happened to the hardware that AI announced not too long ago that some non-Dennis was working on that AI was promoting as official or something? Not the AmigaOne. Wasn't there something else? Where did all that go?


I think you are referring to the Vixxen, by ACK. Nothing has been shown, so it's now presumed to have failed or just been vapourware.
________
Michigan Medical Marijuana Dispensaries (http://michigan.dispensaries.org/)
Title: Re: topic skew
Post by: freqmax on February 10, 2008, 11:33:07 PM
AI = Amiga Inc?, in that case it's not even worth the brain neurons it might occupy ;-)
Title: Re: topic skew
Post by: downix on February 10, 2008, 11:58:14 PM
Quote

weirdami wrote:
What happened to the hardware that AI announced not too long ago that some non-Dennis was working on that AI was promoting as official or something? Not the AmigaOne. Wasn't there something else? Where did all that go?

Smoke and Mirrors
Title: Re: topic skew
Post by: persia on February 11, 2008, 01:28:26 AM
Amiga Inc is actually KMOS, a company that started up about 1999 or so (the real date is purposely obscured to hide from creditors).  They took over the contract with Acer that give exclusive rights to the Amiga name and IP.  They have nothing to do with CBM or the original Amiga Inc.  They have *never* produced anything "Amiga compatible."  In fact their main product appears to be press releases.  Pay not attention to them, you'll be happier that way.

:flame:
Title: Re: topic skew
Post by: da9000 on February 11, 2008, 08:40:56 AM
@persia:

Well said! I especially liked the part "In fact their main product appears to be press releases"
:laughing:
Title: Re: Minimig released for real!
Post by: polardark on February 11, 2008, 11:44:52 AM
That's great news but what kind of box will this fit in?
I want to give one of these to my 8 year old kid brother so that he has something friendly to play games on and learn programming with but without a proper chassi that's like begging him to get electrocuted.
Title: Re: Minimig released for real!
Post by: A6000 on February 11, 2008, 11:55:13 AM
You could give your brother 6-8 A500's for the price of one boxed minimig.
Title: Re: Minimig released for real!
Post by: polardark on February 11, 2008, 12:07:48 PM
Agreed, i could give him one of the A500s i have up in the attic but that would propel him instantly into floppy failure hell, just like it did for me, all those years ago. :D

According to that wikipedia article, the minimig is "nano-itx size". However, it seems that via's nano-itx only has ports at one end of the board. Because of that it looks like you wouldn't easily be able to fit the minimig board in any of the existing nano-itx cases on the market.

Any ideas?
Title: Re: Minimig released for real!
Post by: alexh on February 11, 2008, 12:15:21 PM
It's not an nano-ITX compatible form factor.

Just live with the persepex cover :)
Title: Re: Minimig released for real!
Post by: A6000 on February 11, 2008, 12:18:44 PM
I expect some joker will install a minimig in the largest atx tower he can find.
Title: Re: Minimig released for real!
Post by: straycat on February 11, 2008, 12:19:48 PM
Surely there's a case lined up for this (or at least a recommendation to come from ACube what case to use)?

Seems to me like good marketing to have a case around a computer (or am I barking up the wrong tree?).
Title: Re: Minimig released for real!
Post by: alexh on February 11, 2008, 12:28:15 PM
Barking up the wrong tree me thinks. Tooling cost to make custom cases, even moulded plastic ones are very high.

It's not two bad as a perspex sandwich is it?

http://eab.abime.net/attachment.php?attachmentid=15116&d=1193440340
http://eab.abime.net/attachment.php?attachmentid=15117&d=1193440350
http://eab.abime.net/attachment.php?attachmentid=15118&d=1193440414

If you want to put MiniMig in a case, illuwatar (?) is doing a different MiniMig PCB with headers instead of connectors.

http://www.illuwatar.se/project_pages/mini-minimig/mini-minimig.htm
Title: Re: Minimig released for real!
Post by: straycat on February 11, 2008, 12:36:36 PM
I think the perspex case looks pretty nice and lets you see the 'workings'...

Will the board come with the perspex case? If not will it be available from ACube?

Also doesn't the exposed sides leave the machine open to dust, liquid spills etc or am I just sounding like a 'soft end-user'?!
Title: Re: Minimig released for real!
Post by: Krusher on February 11, 2008, 12:55:08 PM
I think Acube should clarify the Minimig is not a finished computer and cannot run out of the box. The amount of information on their website is too little and confusing to end-users (just look at the questions at this thread alone, all those questions have been answered before, but the information is scattered all around the 'net and in some part, outdated.
Title: Re: Minimig released for real!
Post by: straycat on February 11, 2008, 05:09:25 PM
Quote

Krusher wrote:
I think Acube should clarify the Minimig is not a finished computer and cannot run out of the box.


I suppose what I'm getting at is if you wanted to build an A1200 tower you could source a D-Box from Amigakit.com for example. There doesn't seem to be an similar thing for the Minimig yet. I can screw a motherboard into a case, find a spare keyboard and mouse but building custom cases is not really my thing. Perhaps it's just early days and someone will make something. Perhaps ACube reckon on the glass sandwich effect? Still like the look of the Minimig though, looking forward to some reviews!
Title: Re: Minimig released for real!
Post by: Krusher on February 11, 2008, 05:14:35 PM
Thing is, the Minimig has it's own formfactor, you'd have to build a case from scratch. And you raise a point about the sandwhich case, dust is never a good thing for electronics.

I too like the looks, it's a clean design. I won't be ordering one soon though, too expensive for me and I already have an option on an original Amiga 3000 which will be mine in just under two weeks time.
Title: Re: Minimig released for real!
Post by: ChuckT on February 11, 2008, 06:18:06 PM
It isn't that hard to find options to put it in.  

You could actually screw it to the inside of any computer case just as easily as he sandwiched it in between two pieces of plexiglass.

There are places on the net that will manufacture aluminum cases to your specifications but leave room for a fan:

http://www.ziegeleng.com/
Quote
If there is something you think we should produce, CALL! We always listen to good ideas.
Title: Re: Minimig released for real!
Post by: downix on February 11, 2008, 06:29:17 PM
Quote

A6000 wrote:
I expect some joker will install a minimig in the largest atx tower he can find.


**looks up** What?!??!?

**hides the SGI Crimson chasis under his desk**
Title: Re: Minimig released for real!
Post by: Krusher on February 11, 2008, 06:36:05 PM
Quote

downix wrote:
Quote

A6000 wrote:
I expect some joker will install a minimig in the largest atx tower he can find.


**looks up** What?!??!?

**hides the SGI Crimson chasis under his desk**


SGI???

**tries to cover up his Onyx system

(http://legacy.ensight.com/news/images/smallSGI.jpg)

 :lol:
Title: Re: Minimig released for real!
Post by: Rob on February 11, 2008, 06:36:15 PM
@straycat

Quote
Also doesn't the exposed sides leave the machine open to dust, liquid spills etc or am I just sounding like a 'soft end-user'?!


There's nothing to stop you making some sides and gluing them on.
Title: Re: Minimig released for real!
Post by: alexh on February 11, 2008, 06:47:31 PM
Quote

straycat wrote:
Will the board come with the perspex case? If not will it be available from ACube?

No and no. But you can order them from wizard66.

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=250181224669

Quote
Also doesn't the exposed sides leave the machine open to dust, liquid spills etc or am I just sounding like a 'soft end-user'?!

Yes, yes and yes.

Quote

Krusher wrote:
I think Acube should clarify the Minimig is not a finished computer and cannot run out of the box.

You need to copy kickstart (and a few ADF's) onto the SD card that comes with it, that's all.

Hardly rocket science.

The board is fully assembled, the PIC is programmed and (optionally) it comes with a PSU.
Title: Re: Minimig released for real!
Post by: Krusher on February 11, 2008, 06:52:48 PM
Quote

alexh wrote:
Quote

Krusher wrote:
I think Acube should clarify the Minimig is not a finished computer and cannot run out of the box.

You need to copy kickstart (and a few ADF's) onto the SD card that comes with it, that's all.

Hardly rocket science.


It might be for people who don't own anything Amiga related anymore, at least you need Amiga Forever or an original ROM to be legal. Ok, there are ways around it if you do a good search  here and there but that's not my point. They should post that kind of info on their website. For people who followed the Minimig it's easy to get it running, but imagine a newbe interested into it, buy it and to discover they can't use it?
Title: Re: Minimig released for real!
Post by: alexh on February 11, 2008, 06:56:33 PM
Quote

Krusher wrote:
at least you need Amiga Forever or an original ROM to be legal.

Amiga Forever ROM's wont work of course, cos they are encrypted (but you can just dump them in WinUAE using DumpROM to unencrypt them ;-))

Quote

Krusher wrote:
Ok, there are ways around it if you do a good search here and there

Dont even need a "good search" these days.

http://www.google.co.uk/search?q=Amiga+kickstart+500+extended+rom

Quote

Krusher wrote:
imagine a newbe interested into it, buy it and to discover they can't use it?

Yeah right! There will be no "newbies" buying MiniMig's. I doubt there will be many oldies either. But you never know. I wish Acube all the best, if they get one or two ASIC developers on side (with free devkits, hint, hint, PM me, hint hint) and push the multi-platform angle they could make money.
Title: Re: Minimig released for real!
Post by: Krusher on February 11, 2008, 07:04:07 PM
Quote

alexh wrote:
Quote

Krusher wrote:
at least you need Amiga Forever or an original ROM to be legal.

Amiga Forever ROM's wont work of course, cos they are encrypted (but you can just dump them in WinUAE using DumpROM to unencrypt them ;-))

Quote
imagine a newbe interested into it, buy it and to discover they can't use it?

Yeah right! There will be no "newbies" buying MiniMig's. I doubt there will be many oldies either.


Amiga Forever gives you the licence to use the roms.

And I already had people asking me about Minimig because they where interested but didn't know anything about it, they just expect it to work just like that (Oh so I just hook up a keyboard, mouse and monitor and I have a working Amiga? And then I go on about explaining it has no floppydrive port but an SD card for floppy images, and the rom situation....
Title: Re: Minimig released for real!
Post by: alexh on February 11, 2008, 07:07:58 PM
Quote

Krusher wrote:
Amiga Forever gives you the licence to use the roms.

Ah, now this is where the legal ground gets a bit shaky. I dont think their license extends to using them in anything other than Amiga Forever environment. That's the reason the AF ROM's are encrypted, in a vain attempt to prevent them being written back to EPROM and used in an Amiga. Using them with MiniMig... I think it might fall outside the terms of their license. (And  thus your end user license)

I think the help-desk call that ACube will get the most is "Why doesn't MiniMig work with my monitor?", the answer of which will be "Cos your monitor doesn't support 50Hz vertical refresh!".

Shame no-one got an NTSC build of MiniMig working (which would run at 60Hz), the changes were so minor! Or even better ECS support for 50/60Hz selection in early startup menu of Kickstart 2.04+.
Title: Re: Minimig released for real!
Post by: downix on February 11, 2008, 07:09:58 PM
Quote

Krusher wrote:
Quote

downix wrote:
Quote

A6000 wrote:
I expect some joker will install a minimig in the largest atx tower he can find.


**looks up** What?!??!?

**hides the SGI Crimson chasis under his desk**


SGI???

**tries to cover up his Onyx system

 :lol:

I actually considered putting the MiniMig inside the Crimson (as I have a few empty bays atm) as a little joke at work.
Title: Re: Minimig released for real!
Post by: Krusher on February 11, 2008, 07:15:07 PM
Quote

alexh wrote:

. Using them with MiniMig... I think it might fall outside the terms of their license. (And  thus your end user license)


You've got a point there, so people should buy a real rom then? Then again, I don't think anyone cares if you use an illegal rom on whatever platform/emulator thing you have. It's not as if the Minimig is sold with it.
Gray area though, and I wonder if some unnamed company is going to cause problems.

Quote

downix wrote:
...
I actually considered putting the MiniMig inside the Crimson (as I have a few empty bays atm) as a little joke at work.


Please let us know if you did, I like pranks like that  :lol:
Title: Re: Minimig released for real!
Post by: Caius on February 11, 2008, 07:19:06 PM
Quote
Krusher wrote:
Gray area though, and I wonder if some unnamed company is going to cause problems.

Of course they will. They don't want to make anything related to the Amiga, they just don't want anyone else to do it either.
Title: Re: Minimig released for real!
Post by: freqmax on February 12, 2008, 06:58:20 AM
@alexh:
I think once the userbase become wider than those with hardware/software/amiga wiz-powers. People with HDL knowledge but not electronics etc.. can fix those NTSC things and other features.
As it is now, only those with a substantial knowledge can even enter the "playfield".

Regarding 50Hz, isn't that a TFT controller board limititation?, can't recall any TFT module having that restriction.
Title: Re: Minimig released for real!
Post by: alexh on February 12, 2008, 08:12:46 AM
Quote

freqmax wrote:
@alexh:
I think once the userbase become wider than those with hardware/software/amiga wiz-powers. People with HDL knowledge but not electronics etc.. can fix those NTSC things and other features.

There are 4 great engineers (at least) working on MiniMig (who have FPGA's) and non have worked on this issue. TobiFlex did his software 68k, FrenchShark has ideas of implementing AAA (WTF!!), RedSkullDC has done some work but not ready to release and I think Dennis is on hiatus.

I made the recommendations (code changes) for an NTSC MiniMig when the source first came out, but I dont have a board :-(

Quote
freqmax wrote:
Regarding 50Hz, isn't that a TFT controller board limititation?, can't recall any TFT module having that restriction.

No idea. But 80-90% of LCD's have a minimum refresh rate of 56Hz which rules out PAL MiniMig.
Title: Re: Minimig released for real!
Post by: Krusher on February 12, 2008, 08:24:22 AM
Erm, isn't the Minimig supposed to spit out VGA refresh rates above the 60hz barrier? If not, people are going to be returning Minimigs !! (I missed your edited message, and I didn't know that..)

Most modern monitors hate anything below 60hz nowadays..
Title: Re: Minimig released for real!
Post by: alexh on February 12, 2008, 09:34:19 AM
Quote

Krusher wrote:
Erm, isn't the Minimig supposed to spit out VGA refresh rates above the 60hz barrier?

No. The current release of MiniMig is PAL, thus video output is 50Hz. It's OCS so it cannot change to 60Hz in software.

http://home.hetnet.nl/~weeren001/downloads/minimig1_man.pdf

Quote

Dennis wrote:
Any monitor capable of displaying 50Hz display modes can be used.
Title: Re: Minimig released for real!
Post by: Krusher on February 12, 2008, 09:49:01 AM
Ouch!

See, this is what I mean by lack of information on a website selling stuff. This is mandatory information.

Could it be doubled in the code?
Title: Re: Minimig released for real!
Post by: freqmax on February 12, 2008, 09:49:08 AM
Guess we better fix 60 Hz mode.. Real Soon.
Title: Re: Minimig released for real!
Post by: alexh on February 12, 2008, 09:57:22 AM
It would take less than half a day to convert a MiniMig into to an NTSC OCS Amiga (60Hz).

http://www.opencircuits.com/Minimig_NTSC

I am really surprised that there has been no MiniMig updates (from anyone) since it's release (except T68)

Now if ACube sent me a board (hint hint) ;-)

Quote

Krusher wrote:
Could it be doubled in the code?

Possibly, but most LCD monitors don't sync to 100Hz either.
Title: Re: Minimig released for real!
Post by: Krusher on February 12, 2008, 10:26:59 AM
Quote

alexh wrote:
It would take less than half a day to convert a MiniMig into to an NTSC OCS Amiga (60Hz).

http://www.opencircuits.com/Minimig_NTSC

I am really surprised that there has been no MiniMig updates (from anyone) since it's release (except T68)

Now if ACube sent me a board (hint hint) ;-)

Quote

Krusher wrote:
Could it be doubled in the code?

Possibly, but most LCD monitors don't sync to 100Hz either.


The availabilty of a fully assembled Minimig now is possibly going to generate more interest, since not every coder is handy with soldering, especially the smd parts and the FPGA.

I know about the frequenty range of lcd monitors (mine only accepts up to 75hz) but there are tons of CRT's around that can handle 100hz and upwards.
Title: Re: Minimig released for real!
Post by: straycat on February 12, 2008, 11:24:41 AM
Quote

I think the help-desk call that ACube will get the most is "Why doesn't MiniMig work with my monitor?", the answer of which will be "Cos your monitor doesn't support 50Hz vertical refresh!".
Quote


I don't think my fairly bog standard 3 year old Philips LCD monitor will work (I've had trouble with an old Powerbook Duo docking station in the past. I'm going to check my model on the Philips site this evening). I wonder how many LCDs will actually work? If I have to revert to an CRT monitor it seems quite a retrograde step for a new piece of hardware...
Title: Re: Minimig released for real!
Post by: Crumb on February 12, 2008, 11:47:42 AM
@alexh

I guess that refresh could be multiplied by 1.5

You could show two frames (as the screen may be interlaced) twice and the next two ones just one time, then repeat with the rest of frames. It wouldn't be as smooth as a 50Hz display but I guess it could work well with just slight changes in the code.

It would just involve setting a flag to decide if the same frame must be shown twice or not.

something like this in the refresh loop. Of course, NTSC wouldn't need it:


loop() {
  refresh_screen();

  if ((PAL==true) && (show_frame_twice == true)) {
    refresh_screen();
    show_frame_twice = false;
  } else {
    show_frame_twice = true;
  }

}
Title: Re: Minimig released for real!
Post by: alexh on February 12, 2008, 12:37:31 PM
Yeah, right. Simple as that, I'll make the changes now :-P

"refresh_screen()" Heh, I love it!

Sorry, but you asked for that.

Concept wise, yes, if there is enough BLOCK RAM available in the FPGA then scan rate conversion is a possibility. Scrolling will suck but at least it will work. The PicassoIV's scandoubler has scan rate conversion.

I favour the 60Hz NTSC approach first. A change of crystal and an hour or two of modding and testing (less with feedback from top Amiga programmers, Dennis and Toni Wilen etc.) should get it working.
Title: Re: Minimig released for real!
Post by: freqmax on February 12, 2008, 02:14:13 PM
No need to change crystal, just alter clock_dcm.v to output NTSC colour frequency.
I looked around on TFT specifications, seems 50 Hz is more doable than 100 Hz. As some of them actually supports 50 Hz. The upper limit seems to be 75 Hz for many screens. However I belive there are 100 Hz capable screens. And the onboard RAM could be used as frame buffer if the video output can't be scanned twice the normal rate.
Title: Re: Minimig released for real!
Post by: alexh on February 12, 2008, 02:24:50 PM
Quote

freqmax wrote:
No need to change crystal, just alter clock_dcm.v to output NTSC colour frequency.

Give me the DCM values to produce an NTSC colour frequency from a 4.433619 MHz PAL crystal (which is what ships on a MiniMig)
Title: Re: Minimig released for real!
Post by: freqmax on February 12, 2008, 10:52:53 PM
Frequency 3.575499 MHz with multiply=25 division=31
Ie 4.433619*(25/31)
If 0.001 MHz deviation works out alright.
Title: Re: Minimig released for real!
Post by: alexh on February 12, 2008, 11:23:52 PM
How many DCM's are there in the XC3S400-4PQ208C? Four?

Can you cascade them?

MiniMig (NTSC) uses the following clocks:

3.579545 MHz
28.63636 MHz
7.15909  MHz
0.715909 MHz

http://www.amiga.org/forums/showthread.php?t=30550

I am not sure the DCM instantiated in MiniMig has all possible I/O. Making these clocks (within tolerance) may be possible.

http://www.xilinx.com/support/documentation/user_guides/ug331.pdf

I dont really have a working knowledge of these things.
Title: Re: Minimig released for real!
Post by: freqmax on February 13, 2008, 05:18:57 AM
I think it's possible to cascade DCMs. And XC3S400 & XC3S500E both have 4x DCMs.

These clocks can be done without DCM (provided the 28MHz):
28.63636 MHz / 8 = 3.579545 MHz (colour clock)
28.63636 MHz.. (agnus)
28.63636 MHz / 2 = 7.15909 MHz (m68k cpu)
28.63636 MHz / 40 = 0.715909 MHz (E clk)

The key issue is timing, thus the colour coding schemes which another person mentioned is quite irrelevant as output is direct RGB.
I don't think the colour frequency crystal is needed at all actually. One could simple hookup to the MCU crystal and thus eliminate one crystal + associated passives.

I think a pure HDL (http://en.wikipedia.org/wiki/Hardware_description_language) solution is doable if the slight timing deviation is tolerable.