A4000TX ATX Amiga motherboard

hese

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AmiBayer
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Let me introduce to you the latest Amiga motherboard project I've been working on.

A4000TX ATX motherboard
, the first Amiga based motherboard in ATX form factor (actually a hybrid ATX/EATX form factor).
A4000TX is an A4000cr motherboard and daughterboard embedded together with a few additional features.
The motherboard is fully hand-routed like the A4000+ Alice motherboard was.

The specifications of the A4000TX Lisa rev 1.0:
- fits into (E)ATX case
- uses standard ATX power supply
- Amiga AGA custom chipset
- CPU slot connector for accelerator cards
- on-board 68030 CPU
- on-board 68882 FPU
- 16 MB Fast RAM
- 2 MB Chip RAM
- four full-length Zorro III slots
- three ISA slots
- extended video slot
- 3.5" IDE port
- internal floppy port
- PS/2 keyboard port supporting Amiga and PC keyboards (PC work in progress)
- PS/2 mouse port (work in progress)
- Amiga mouse and joystick ports
- serial and parallel ports
- 15-pin VGA port with 15kHz RGB output
- 24-pin breakout header with full RGB port support (for external scandoublers, genlocks, SCART cables, etc..)
- 3.5mm stereo jack
- on-board RTC with battery

Blank PCB

Here are pictures of the blank pcb.


The board is a four-layer PCB, which is quite crowded with components and traces both on the top and bottom side.
There is no space left on the board for many additional components.

Assembled PCB

Here are a few pictures of the assembled PCB.




Motherboard installed in an ATX case

The motherboard was installed in a standard ATX case.



Motherboard I/O connectors

Here is a picture of the back of the case showing the I/O connectors.


I/O connectors from top left to bottom right are
- PS/2 keyboard (Amiga or PC)
- PS/2 mouse (PC)
- Amiga mouse port
- Amiga joystick port
- serial port
- parallel port
- VGA port (15kHz RGB output)
- 3.5mm stereo jack

Behind the VGA port is the 24-pin breakout header to which you can plug in your custom-made cable (for scandoublers, genlocks, SCART, ...).

A4000TX motherboard dimensions

The picture below shows how much free space is required at the bottom of the case for fitting the motherboard.


The A4000TX motherboard is a hybrid ATX / EATX form factor board.
The standard ATX motherboard dimensions are 30.5cm x 24.4cm, EATX has 30.5cm x 33.0cm (height x width) (EATX = Extended ATX).

The aim was to create an Amiga motherboard that would fit to most ATX cases and still support full-length Zorro cards.
Top side of the motherboard has standard ATX dimensions (24.4 cm wide).
The bottom side had to be made wider (30 cm) so that full-length Zorro cards can be used with the motherboard.
The motherboard can be fitted into a standard ATX case if there is enough space at the bottom of the case. A full-length Zorro card is 34cm long.
Alternatively the motherboard can be fitted into an EATX case.

In the picture the motherboard was installed into an Enlight ATX case that takes standard size ATX motherboards only, no EATX.
And yet the motherboard fitted in well.

Epilogue
The motherboard is fully working (except the PC keyboard and PC mouse support that need fine tuning).

I have some prototype boards that I will be putting for sale soon if there is interest.

I would like to hear what you think, is there a demand for an ATX motherboard like this.
And also if there are some features missing that you would like to have in some later revision (reasonable please, can't embed a PPC there...).

All kind of discussion is welcome. Thanks.
 
What a fab idea this is ! :cool:

Cant see the actual pics here at work but will look when I get home.
 
hese, this is super cool - if only for showing off what individuals in the community are capable of in comparison to others talking and rambling all the time instead of delivering. ;)

That being said, at least for myself I wouldn’t really have a use for it as I prefer having my Amigas in their original cases.
As I know myself though, I might still consider getting one just to own it and maybe another for the fun of assembling it ;)

big thumbs up!
 
That is really awesome hese!
The one and only thing I'm missing is the 64MB or 128MB hack to get more memory.

I hope I can put this next to your awesome Alice 4000D in near future :)
 
Coooool! Awesome. I am interested in a prototype. Maybe a later revision can have more zorroslots.
 
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A4000TX ATX Amiga motherboard

Dear hese,

what a luck for the community to have skilled and participating members like You, among chosen others of course.

I always waited for someone adopting A4k mainboard format to current tower standards: no need anymore to build physically suitable towers manually.

And continuing a wish list, and aiming at integrating other developments here and elsewhere in the amiga scene, this board needs the ISA slots technically replaced with at least PCI slots. That would open even more doors. Furthermore, if I remember correctly, there was a scheme (open source???) of an OpenPCI suitable daughter board with a comparable configuration, which, if integrated in Your board, could even make the PCI ports directly reachable from the Amiga side.

That would be miraculous ?
 
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I struggle to find the words to express how insanely amazing this is! :blink:

Looking back in the past, to all the half-arsed attempts bundled in with nothing but talk/air. Followed by the typical dissapointment at the end (vapourware :blased:).
Hese has made them all look pretty dam useless!

I would love to own one of these boards! I want to say thank you creating something like this :)
 
I like the format of the board and it fits into the usual PC case. I am curious if running the keyboard and mouse in the prototype version is difficult? In the final board I would like to use the MC68030 processor in the PGA version, also MC68882 PGA.
 
WOW! Also interested in a prototype, this is so cool! :O
 
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Has many have said: this is Absolutely AMAZING!! (y)(y)

:bowdown:We're not worthy, We're not Worthy!!:bowdown:

Worthy.jpg


Well done hese for this and your Alice PCB's
 
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I would for sure take one! Is there space for a USB HID keyboard? Small mezzanine perhaps?
 
Great job! We are fortunate as a community to have talented individuals like you!
I can see interest in a ATX form factor, especially with all those fixes you built in. I would get one such board myself.

Out of curiosity, is there room to accommodate all 4000 accelerators?
Would it be possible to build in the IDE PIO-2 and 64MB Fast RAM hacks?
Could the onboard 030 be clocked at 50MHz?
 
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Along with the 64MB memory 'hack', it would be great if the 1MB Kickstart hack is also added. These would be simple to add, and would be a great improvement.
 
In this stage is the time to do some improvements on the board. Like adding USB, CF/SD, see also the Amiaga 1200 Reloaded page: http://wiki.icomp.de/wiki/Commodore_A1200_Reloaded

When ready? Start massive production this will be hot!!! You will be a legacy for Amigians. Putting this in a checkmate 1500 or probably in one of the next kickstarters of a1200.net, this will be amazing.
 
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