Månadsarkiv: april 2025

ReAmiga 3000 motherboard is fully built and tested

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ReAmiga 1.4 motherboardboard

I had an old Amiga 3000 in my stash that I got in a trade years ago. It was traded to me as fully working but never worked no matter what I did. When the ReAmiga 3000 project became known I wanted to save the broken A3000 by building up a ReAmiga 3000 motherboard with the parts from the broken Amiga 3000.

I did not have the soldering skills 15 years ago to do that, but today is a different time (and maybe I was better off 15 years ago with just one A1200 instead of a fleet of Amiga replicas) – So the broken Amiga 3000, or at least what was left of it has gotten a new lease on its life!

Find out more about the ReAmiga project here.

I have already started soldering in stuff that I should have waited with, as usual it is difficult to wait for the right parts to arrive at the post office before starting the project properly.

So this is how it started out. This time I started off with a motherboard with all passives already mounted which saved a ton of time. Interestingly though, I found one error where the BOM specified a tantal capacitor and a regular ceramic cap was placed instead. It was an easy fix!

Here is the original Amiga 3000 motherboard which acted as a donor card

The components I used from my broken Amiga 3000 was the full chipset (more on that later), the special memory chips for the scandoubler and some odd pieces here and there such as the trim pot, power socket, disable switch for the scandoubler and the stacked female 25 pin port.

I usually like to keep some parts from donor Amigas in new builds not just the custom chips.

Believe it or not, I actually used the same KEL connector for the CPU board that was mounted on the broken A3000, it was a painful experience desoldering it.

I also wanted to save the two edge card connectors for the daughterboard, desoldering them was a major hassle since the ground plane is very strong on the A3000, instead I ordered replacements from AliExpress.

Chipset gave me a surprise

As is derigeur when building an Amiga replica, there are always some kind of surprise no matter how much prepping one does.

So there are some very expensive chips on the Amiga 3000. First is the Amber chip which is part of the scandoubler/flickerfixer. Then there is the DMAC chip both which costs a ton of money.

I did not know if these where working before starting the build and I was not prepared to pay 200-250+ euros for replacements if they did not work. Luckily I could confirm they where working once the motherboard was fully built. But surprised I was, the Ramsey chip was broken. Luckily I had a NOS Ramsey 07 chip in my stash and as lucky as I was a Buster 11 was offered for sale on a local website meaning I could skip the Buster 7 I had from the broken A3000.

Lets find out if Ramsey 07 plays well with my revision 02 of the Super DMAC. I will just have to find out once system is fully up and running with Workbench installed. If not I will need to track down a Super DMAC replica.

Next steps….

Now all I am waiting for is a replica A3000D case to be available and I will order one in black ASAP. I am also doing a daughter board for it which I will post about later in the year here.

FlashROM 40 & 42 pin Kickstart Flash EPROM

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A weekends work resulted in 17 FlashROMs – this is actually the second batch I have made for myself

There are a couple of different hardware Kickstart solutions for the Amiga. The most proven one seems to be 27C400 chips that you can program in a T48 (with an adapter) and erase with UV light. If you buy a Kickstart from a retailer, that chip is probably an 27C400 EPROM. I dont like the UV light eraser, and the 27C400/27C800 chips are expensive, so I went looking for another solution that had the possibility to scale up in volume fine.

I don’t know what it is about burning Kickstarts for the Amiga but the topic is highly confusing at first. Not only do you have to have the correct byte swapped file (or build the ROM file correct if you want to run a custom ROM) but you need some kind of adapter to be able to program some of the solutions on modern cheap programmers.

This is not a tutorial in how to burn a Kickstart or how to build your own Kickstart, I suggest you schedule a weekend to do a deep dive into that topic. Then it sort of makes sense (I think).

No doubt in the future something like the KickSmash will probably be the defacto standard and I contemplated ordering a batch of PCBs and building a suite of KickSmashes for my fleet of Amigas. Instead I went with the FlashROM, because right here and now, it is possible to run FlashROM on all Amiga models while the KickSmash fits the Amiga 1200, Amiga 3000 and Amiga 4000 (and A4000T).

With new Kickstart ROMs being released fairly regularly these days. And the need to be able to build your own Kickstart so you can f.e. add ehide.device for a TF1260 system or PeterKs Icon library to the Kickstart, an easy way of updating Kickstart is IMHO, a must have, these days!

What is the FlashROM?

The FlashROM is basically a Kickstart replacement that you can program yourself – FlashROM has 1024 KB of space, meaning it can take two Kickstart files. This is great as it is possible to run one Kickstart ROM and one DiagROM rom on the same chip.

You change what bank you want to be active by setting a jumper on the pinouts between GND and A18.

If you do not need dual ROM functionality, just concatenate the same ROM twice and flash it to the EPROM.

Programming a Kickstart to the FlashROM

I use a T48 to program chips, an adapter was needed to be able to flash a Kickstart ROM to the FlashROM. I actually chickened out and just ordered a ready made programmer to reduce the complexity of this project, you can find out more information about the FlashROM adapter on Levo’s website.

Using the adapter is a breeze, just have to connect the wires correct and everything works just like programming any other chip. Erasing the EPROM is no different.

40 pin FlashROM

40 pin FlashROM, I notice it was not cleaned properly as you can see flux residue left at the top left corner

Here is the 40 pin FlashROM, this will go into my Amiga 500, Amiga 2000 and Amiga 4000 and so on.

42 pin FlashROM

42 pin FlashROM for my Amiga computers that can take a 42 pin Kickstart chip (such as Amiga 1200)

Here is the 42 pin FlashROM, this will go into my Amiga Denise clone, Amiga 4000TX and Amiga 1200. One benefit of running it in a ReAmiga 1200 is that the jumper on the motherboard select which bank you want to be active.