Hi there, it's been a while. Somewhere down the line life happened and wait, not one, not two, but three Vintage Computer Festivals have happened since my last blog post. Three that I participated in, that is.

Seeing people that are not projected on square glass pieces was more time consuming than anticipated, and so typing text into this little square glass piece had been down prioritized. After a distant panic of one of my readers about "All good things..." meaning an end of this blog, I did promise some updates.

Last year I had signed up for a booth at VCF east to show off some of my little adapters, like the ROMY redesign that I had made as a starter project. I got a bit of cold feet last minute as three tiny PCBs on a large table are everything but impressive, and so - as there were no other Amiga booths present - decided to just bring a few machines. It turned out to be a great event and I got to know a lot of the local vintage community in person, including the amazing Liza Loop, who told me about the BBQ parties she had with Jay Miner back in the day. These stories are what we are here for, at the end of the day. There is a lot of technology out there, and a lot of PCBs everywhere, but the history of our technology tells us the tale of Silicon Valley and its dreams.

In October Chris Hooper and I made it up to AmiWest in Sacramento. It turned out to be a lot smaller than I anticipated (and I anticipated for a good 30 some years here, this was my first AmiWest), and a lot better. I had just picked up an A4091 SCSI controller on my travels to Germany before, and we were chit-chatting that with the Dave Haynie Archives and this board, we could indeed do a reproduction of the board. That's crazy talk. Or is it now.

It was a busy winter for Chris and me, and by April I traveled to VCF East with three reproduction A4091 boards in my bag and equipped with a slide deck to give a talk about this project.

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... come in threes, they say, or "Aller guten Dinge sind drei" in my native tongue German. And so I set out to make a third and final attempt at reliably delivering great 68040-to-68060 adapters. Remember, earlier in my adventure I built one of these adapters with a PCB made by OSHpark. I was so excited, that I sold it on eBay and started to make another one. And failed. And another one. And... Well, you get the story here.

In my second attempt I found out, that I had forgotten to refresh the fill zones in KiCAD - What a rookie mistake, that left half a dozen 68060 PGA sockets dead, soldered onto PCBs where VCC and GND were never connected to the mainboard. The good news? No Amigas, and no 68060s were harmed in the production of that episode. But I promised, I would get this working. At least to myself. I had also disliked some of the characteristics of the old design.

• I had to dremel the sockets I got into shape because they tried to occupy the same space as the other parts on the PCB, in clear violations of the physical laws of this time-space.
• The interconnect between the two boards was oddly misaligned with the rest of the pins, making it impossible to use the substrate of the socket to keep them nice and tidy (and giving another reason for more dremeling. UGH)
• Compared to the original design the KiCAD version by richx used single resistors instead of resistor networks. For the sake of space, those could be replaced by nice little 0603 RNs.

An evening with KiCAD and a few more days of waiting on a PCBway delivery, and here it is:

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Alright, there is some progress on the front of my 68040 to 68060 adapters. In the last month I have made a serious improvement of my lab: a simul focal microscope with double boom stand.

This has vastly improved my ability to see what I am actually soldering, instead of almost flying blind.

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This led me to attempt another approach to making 68060 adapters, this time I could maybe be less of a butcher with a soldering iron. And with so much visibility, it makes sense to learn from the others out there. Adam Polkosnik has perfected his way of making 060 adapters and was kind enough to teach me all of his secret tricks, some of which I will document here.

My favorite of these tricks is to use actual PGA sockets instead of cutting 400 single pins out of pin headers. The original 68060 adapter instructions suggested to cut the VCC pins between the upper and lower PCB. A smarter and cleaner way that I learned from Adam, is to use a third PGA socket to keep the distance and separate the 5V and 3.3V circuits safely. This gets rid of a very destructive part of the construction of these adapters.

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Don't you know the feeling when you're just on cloud 7 with your Amiga?

Maybe you remember the action replay for Amiga 500 which let you scan memory for lives and mods? Or you miss a nice and handy debugger when debugging that latest 68000 assembly of yours?

ikod.se had the right solution for your Amiga 1200 or 4000: an int 7 adapter. It is easily assembled with only a 52pin PLCC socket, 3 1n4148 diodes and a pin header and switch.

The thing is, it's hardly worth, or even possible, to order anything in single quantities when doing PCBs. The price for 10 might just be the same. So let's find solace in the soothing effects of soldering

This was one of the projects that I used to practice working with solder paste and hot air. In the picture above I used a little bit too much in some places.

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Back in the late 80s and early 90s, when the Amiga was relevant as a technical revolution, I was never able to lay my hands on anything beyond an 68000 with 7.14MHz. Years later, around 1997, I acquired an Amiga 3000 with 25MHz as part of one of my university side gigs of porting software from various UNIXes (in this case SCO Unix) to Linux. But a 040 or even 060 was far out of reach until I was well into my first full time job at SUSE Linux when I got a Cyberstorm MK1 that - as we know - doesn't fit into the A3000. Long story short, the first time I actually ever ran an Amiga with something faster than the 68030 @ 25 was around .... Christmas 2019.

As life happens, and we sometimes overcompensate for our youth's desires as we grow older, I added one of Chucky's A3660 rev 1.1 to my collection, (built by Nicolas Baumgardt who lives in Switzerland, but only few miles from where I grew up and hacked on the Amiga back in 1987) that so far consisted of the A3640 that screamed for pad replacements and recaps.

Along the way I learned that the Amiga CPU local bus is really a 68030 bus, so memory access on everything above a 030 has to be translated and is then slightly slower than with an actual 68030. Ouch.

I also learned that the Zorro III slot is not really all that great. Well, Super Buster is not in its current implementation. While the theoretical maximum of Zorro III beats the first PCI standard, the actual implementation is stuck at 8-10MB/s memory access speed. We need an update Dave Haynie! Then our BigRAM+es could be really super awesome!

But back to ... back to the 68060. Once I tasted the sweet excess of the Motorola flagship's raw CPU power, and when I got my beautiful Hakko soldering station, I had to upgrade my 3640 to a 060 processor as well.

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I have not been keeping up well with this blog in the last few months. Starting a new job definitely does that to this sort of project. I did spend time behind the scenes on some cool things that are in various stages of completion. Some involve 3d printing with the Prusa i3 MK3s that I assembled this summer. Others are following the dream of creating new and exciting Amiga custom chips.

But overall, it has been harder to spend time in the Silicon Valley garage also for one reason: Winter is coming! And spending time out there for projects has become a lot less attractive.

Today the solution to keeping the endless stream is ideas flowing has arrived. It will help the atoms dancing and the feet warm during nights of soldering. As the year nears the end, and many projects are waiting to be realized, this will heat up the velocity:

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