Minimig PCB run - interest thread

[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.

[amigadave]

Xenepp wrote:
Just to clear a couple of things up:

Would there be any way of making the VGA port output composite sync? If so, that enables the usage of a RGB SCART cable for TV hookup.

Composite or S-video would need a separate video encoder. There's no room on-board for this. You can probably modify an old Amiga RF modulator for RF output though, they ran through RGB, which afterall, is all VGA is. You can probably use an RGB SCART lead with most European TVs too as the Minimig outputs 50hz. All you need to do is tie the horizontal and vertical syncs together to get composite sync for normal RGB (doesn't mean you can use composite video this way).

Also ready-assembled is much better. I don't see the point of a bare PCB (for the majority of potential customers...)

I beg to differ. Most guys who'd want to have a go at this project don't have the means to fabricate the PCB. It's really the hardest part to get past, the rest is trial and error.

IIRC, Dennis had jumpers on the Minimig to switch from 15kHz to 30~31kHz for the RGB output to be able to use old Amiga monitors, or modern VGA monitors.  In fact I had written him about it and have the reply somewhere on another computer at my home (on the laptop today).

One question: There should also be a jumper to switch from 50hz to 60hz for the North American and Japanese markets interested in this project.  Please don't make it 50hz only.

And lastly, GO JOEL!!!  This is absolutely the most exciting Amiga news in years and I think it is great that it is Open Source and was developed by one single person that was not a greedy company out to screw the Amiga community (again).

What is the current count of people interested in boards?  Many of us want more than one board, what is the total count of boards wanted?

[amigadave]

Has anyone calculated what all the parts to produce a completed Minimig should add up to, minus the PCB itself?

I am tempted to try the Laser printed PCB trick and buy all the parts to put on it.  If I am unable to produce the PCB myself successfully, I would still have all the parts needed to put on a PCB produced by one of the members here that eventually produces a run of PCBs.

I think I saw somewhere in one of these threads that Dennis has also provided the Gerber file for his v1.0 Minimig PCB layout.

I also wonder what the total count of boards wanted is from this and all other threads.  It must be well over 100 by now.

[amigadave]

basman74 wrote:

amigadave wrote:
Has anyone calculated what all the parts to produce a completed Minimig should add up to, minus the PCB itself?

For 100 off, My guess would be like this (prices are in USD) most prices were obtained from Digikey:

Per unit cost - Minimig Rev. 1.0

FPGA:          $19.25
PIC:            $5.15
PCB:            $7.00
2 x SRAM:      $14.50
68k CPU:       $11.00
misc IC's:      $1.80
MMC slot:       $2.20
Connectors:     $5.50
Headers:        $0.50
Passive parts:  $4.00
--------------------
Bare PCB:       $7.00
--------------------
parts delivery: $3.00
--------------------
Subtotal:      $80.90
--------------------
Assembly:      $25.00(hand assembled?)
--------------------
Unit cost:    $105.90
 
Deduct $32.00 from the above to give you your answer for parts cost minus PCB and assembly.

Cheers,

Valentin

PS: Using the 'Toner transfer' method to make the PCB would prove challenging, given the presence of the PQFP

Thanks Valentin,

I have reconsidered and will wait until someone (maybe you) produces fully assembled boards to purchase and complete the rest of the project to have my own Minimig.

Unlike some others here, I only want it to run games on in the smallest form factor possible.  If it could be fit into the base of a joystick that would be ideal.

I don't see the point of making it with PCI, USB, etc. extra connectors and 68030 or faster capabilities.  The majority of Amiga games will run on the 68000 w/1mb RAM.

I would like someone to take Dennis' work and expand on it to make a better Amiga in the future, but that is a completely different project that will take considerably more work.  When it has progressed to a point which exceeds my current 68060/50mHz & 604e PPC/233mHz Amiga I will buy that project too, but I think that is a year or three off into the future.  Someone, or some group of geniuses here please prove me wrong.

For now all I would want is Dennis' original concept, with his suggested fixes, produced in the smallest package to fit into the base of a joystick, or if not possible, perhaps into an old 1010 external floppy drive case.

Lots of interest here, let's get this done before Christmas so we can all enjoy the fruits of our labor putting a Minimig together.
 :-D

[amigadave]

I hope that most here will agree with the common sense that Dennis and others are suggesting for the first run of v1.1 Minimigs.  Then v2.0 can be discussed and designed over the next two weeks :-P (couldn't resist the Amiga joke of the decade) and another production run with the new design and compatible verilog code to make it work can be tested by a few brave souls.  

I am good friends with the owner of a plastic injection molding business that I can talk to about doing a limited run of cases for a Minimig joystick, if the PCB can be designed to a reasonable size for such an implementation.  Dennis' original size would work for such and only be a little over sized compared to most other Amiga joysticks.  I like the 12cm by 12cm form factor with the ports as Dennis had on the v1.0 design.  I could easily design a replacement bottom half for a joystick I already have in mind to accept the Minimig and complete the casing with the joystick on top.

[amigadave]

Fixer wrote:

Do we even need AGA for this thing I wonder - is Dennis even considering it?

No, Dennis has already stated before that he is not interested in doing AGA, but would hope that others would build on what he has started.

[amigadave]

Thanks Hojo_Norem,

You saved me from making that count.  I have been wondering how many there were and was going to start a spreadsheet with all the member names that wanted boards and a count of who wanted more than one Minimig and another column that showed who wanted completed boards as opposed to those who want bare PCBs and a bag of component parts.

130 boards should be enough to make it worth someone's time and trouble and get a better price on some of the parts.  Who is going to step up and be the first to take charge of getting the first run into production?

I am ready to buy at least one, if not two boards.  Preferably the original size of 12cm square.

Ready...... Set........ Go Minimig!  The replacement A500 in the palm of your hand.

[amigadave]

Just looking at the jpeg of Dennis' v1.0 Minimig again and thinking what a beautiful job he has done with the design. Maybe I am easier to impress than some of you, but I think Dennis' design is nothing short of a work of Amiga computer ART!  (Love the Galaxy Quest quote too)

I would really like to have a duplicate of HIS EXACT BOARD layout, including the same silkscreen text.  The only changes I want are the fixes he has suggested and I would prefer NTSC video timing, or the option to switch from PAL to NTSC and back via a jumper.

Can anyone make this request a reality?  

Dennis, if you are reading this and have access to one more of the original 4 boards you produced, I would gladly buy it. (I know this is not a real possibility)

[amigadave]

freqmax wrote:
http://rapidshare.com/files/46669345/minimig.sch.html
Minimig schematic complete, minus the joystick port.
I used 1Mx16 ram instead of 2x 512kx16.

Headphone back-emf?
* The +1.25V and +2.5V can be connected to +3.3V to save power. Due P_heat=U_drop*I.
* Howcome the many connections to the fpa isn't in numerical order?
* What is the value of C37 100uF/6.3V ?
* Why is R42 present?, it's just sitting between +1,25V and GND.
* Howcome (54,55,56) M1,M0,M2 is connected to VccAUX, doesn't it need 3.3V?
* The 'SPI_DOUT' from the fpga and SPI_DOUT from the sdcard (via 1k) can drive eachothers output, maybe this can be resolved with an or gate or such instead?
* Maybe the keyboard and mouse can share connection?, I've seen that on laptops asfair (saves i/o).
* There's no over/under potential protection for keyboard or mouse?, like video output have. Howcome?
* Maybe the rs232 output of mcu and fpga can be shared without a jumper by setting an AND-gate between. Because the default level for rs232 is "1". And thus any transmission will produce "0", and if the other maintain the rs232 "1" resting state. IT should work.

Posting a image link to a site that requires us to register is a waste for those (like me) that don't want to bother registering at that site.  Can you upload the image here?

P.S. Dennis, I hope you don't mind me using a reduced version of your jpeg for my Avatar for a while.

[amigadave]

CD32Freak wrote:

Posting a image link to a site that requires us to register is a waste for those (like me) that don't want to bother registering at that site. Can you upload the image here?

@amigadave
You don't have to register to download the file, just click the free button down below :-D

My Bad :-(

[amigadave]

Troels_E wrote:
I would like one Minimig, assembled please.

And as small as possible, doesn't matter if it fits a standard tower as I would do a custom one anyway.

What sreenmodes are supported?

Dennis' design has a jumper to switch from 15kHz to 31kHz RGB output so it will work on both old Amiga monitors like the 1080 and 1084, or will work on newer VGA monitors.  I think the timing is PAL only at this point, but hope that will change to allow NTSC output from some boards, or switchable back and forth between PAL and NTSC.  The software mimics an OCS A500, so display resolutions should be in the same range as an original PAL A500 (since I am in an NTSC display country I can't remember the exact numbers for PAL displays at the moment).

It is great that Dennis built in a scan doubler so modern monitors can be used.  Some members are asking for composite output so TVs can also be used.

[amigadave]

@JosephC,

Minimig's creator never claimed that it was "hardware compatible" with all A500 chips, just that he was trying to make it able to run "most" OCS Amiga games.  I don't think he ever intended it to be a complete replacement for Classic Amiga computers.  It was just a fun challenging project to see if it could be done.  See Jens "A-Clone" project, which is more like what you are asking for, a complete hardware replacement of the custom chips on an A500.  Jens demonstrated it at AmiWest last year where he had completed the replacement of 2 or 3 custom chips with 100% accurate function by plugging his PCBs into the chip sockets.  Once he has completed the designs, I believe his plan is to put the replacement designs into silicon and we will finally have a source for replacement custom chips for the Amiga and possibly a way forward to some enhancements to the original Amiga designs.

I am writing all of this just from my questionable memory without going to Jens website to confirm, so take it with a grain of salt and go check out what Jens is doing for yourself.  Minimig is a completely different project with a different purpose.

My 2 cents,

[amigadave]

Xenepp wrote:
Little update here, Dennis is updating the PCB afterall to V1.1, we decided it was best if he did it since it'd take too long for me to recreate it in Eagle and don't have a gerber capable editor.

Patience is key here as he is very busy with real world commitments. Once I have the new PCB though, I'll send it to my guy in China and from that point it will be two weeks before the boards arrive with me to test.

I'll keep you guys posted.

 -Joel

Great news Joel,  I don't know how I missed your last message earlier.  

Can you reply with a brief summary of what changes are being made for the v1.1 Minimig PCB?  Also, can you answer the question which form factor is Dennis using for v1.1, is it still 12cm by 12cm?  Will your assembled boards have the ports Dennis used, or pin headers, or will we have a choice of either?  Do you have a price for the following:

1)  Bare PCBs
2)  Bare PCB w/kit of all parts needed to complete a Minimig
3)  Assembled Minimig boards with all parts installed

Thanks for taking this on and getting these boards manufactured.

[amigadave]

jkonstan wrote:
I have actually had two bare MiniMIG 1.0 PCBs produced for myself based on Ver1.0 gerber files/layout, and I am gathering up the parts in order to assemble them by hand.

 :-)

What???  You did a production run of ONLY 2 Minimig PCBs with well over 100 members here waiting and asking for someone to produce a board, either assembled or bare, for them?

Congratulations, but I must say I am disappointed that you did not ask for the money to run more PCBs for members here.  I will gladly pay anyone that is willing to produce a Minimig for me, as I do not feel confident in taking on such a project myself, without help from those more knowledgeable and skilled than myself.  I am good with a soldering iron, but would prefer to obtain an assembled board that is an exact copy of Dennis' original v1.0 design with any v1.1 fixes that can be integrated.

So, if there is anyone else that is preparing to produce another run of Minimig boards?  I am ready to buy one or two.

[amigadave]

jkonstan wrote:
Amigadave,

I fabbed these two blank PCBs so that I could try to help with the development/enhancement of MiniMIG. The two Ver 1.0 blank boards were fairly pricey (over $25/each without electrical test) as compared to some of the other better efforts that were already on going to produce a bunch of cheaper blank PCBs. An AROS related individual/group was going to produce a batch of the original Ver 1.0 PCBs for sale, and the original starter of this thread had the mass production covered for Ver 1.1 of this updated PCB artwork. I thought that would have everyone pretty much covered without someone else mucking up the waters.  I really do try to stay focused on the technical side of things.

 :-)

I didn't mean it to sound like I was jumping down your throat.......just disappointed that a larger production run of Minimig boards has not been completed yet.

I meant it when I wrote congratulations.  I am happy that you have two boards to work on and I am also glad that you appear to be working on improvements to the original design and/or code.

Hopefully it won't be too long before some assembled boards are available for general distribution (sale).