Kategoriarkiv: Amiga hardware DIY

Multifix AGA Amiga scandoubler and flicker fixer

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The Multifix scandoubler is another great hardware project by talented Amiga hardware DIYselfer Matze. Read more about the Multifix AGA scandoubler and flicker fixer here.

What is a scandoubler and flicker fixer?

In my humble opinion a scandoubler is a must have for an Amiga. It lets you display native screen modes on a regular PC monitor. A flicker fixer is great to have also, it means you can use higher resolutions screenmodes without nasty flicker. There is however less reason to use flicker fixer modes in Workbench if you have an RTG graphics card since an RTG screen is faster than a flicker fixed screen typically.

Building and testing the Multifix AGA scandoubler and flicker fixer

I have to be honest, the first time I looked at the project page I did not have a clue on how to build it. But after having finished a couple of projects and being more used to projects with less documentation I felt ready to tackle this beautiful scandoubler.

The Multifix integrates well with the GBAP2++ Amiga RTG graphics card, being able to hook up directly to the graphics board. Doing so auto switches output between scandoubled/flickerfixed output and RTG output meaning, you could run the graphics board and scandoubler in one aligned Zorro slot and video slot.

It is difficult to say something about the video output since on a CRT the picture quality is probably superb. I do not have a CRT so can only test on modern flat screens. The picture quality on my TFT is not as good as I get from an Indivision or ZZ9000. I get some banding on the screen, but I have seen worse banding with other VGA scandoublers and the colors are correct – overall I am very happy even if the picture quality is not as sharp as those other devices I mentioned. And the picture quality might be even better with another flat screen.

OKI M5142 and NEC 42101 are also used on the Amiga 3000

Difficult to find chips

There are some chips on the scandoubler that is a bit difficult to find and it is the OKI M5142 and NEC 42101. One card uses six chips of each. As usual, some chips pop up here and there on Ebay and there are the usual places where you can find these chips (Aliexpress). If you do some research you might even find clones of these chips that are fully compatible.

ADV7120KP30 is the same chip the A4000D uses, I got 5 from Aliexpress last year for my A4000D build so had 4 to chose from.

Anyways, building this Amiga scandoubler/flickerfixer is very straight foward.

Ports and switches on the back

The backside of the Multifix AGA is kind a busy, more so than a typical scandoubler that usually only has a 15 pin female VGA port.

You might wonder why it has two USB ports, two switches and an audio port on the back. I did too, and it is not quite obvious why by reading the documentation on Git-lab. Turns out, the USB ports are powered only, meaning, you can use these for devices that uses USB power such as VGA to HDMI converters. There is a pinout on the Multifix PCB so you can hook up the USB ports to your USB card saving one bracket space. The switches disables the flicker fixer functionality and the scandoubler functionality (useful if you just want to pass through video output). And what about the audio output? I think the card picks up audio from the video slot so you might be able to get sound from here (I am not sure though).

Oh, and that bracket, it was not made by me, I found a guy on a1k.org who could sell me two (I plan to build another), I could never make one that good looking myself.

Practice makes you perfect (when building an Amiga motherboard)

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Motorola 68030 25Mhz on the A3000D motherboard (ReAmiga 3000 SMC version)

I am working on a ReAmiga 3000 motherboard. I am in no rush to finish it, taking it really slow ordering one set of parts at a time. Last week I got the 68030 so I decided to solder it on the motherboard this weekend. Hopefully I will be able to do a test drive before Q1 is over!

GottaGoFaZt3r 256 MB Zorro 3 memory card

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GottaGoFaZt3r 256 MB RAM Zorro 3 card for the Amiga

GottaGoFaZt3r is a memory card for Zorro 3 big box Amiga computers that you can build or buy premade. Find out more information about the GottaGoFaZt3r Amiga memory card here.

Amiga with a Zorro 2 bus supports up to 8 MB memory on the Zorro 2 bus, that memory is shared with other devices on the bus so if you have a graphics card with 2 MB you can only have 6 MB additional fast mem on the Zorro 2 bus. With Zorro 3 that is IIRC increased to 1 GB.

Phase 5 Fastlane vs GottaGoFaZt3r

Before this card was released there was not a huge offering of Zorro 3 memory cards, the most famous was probably the Fastlane from Phase 5, a huge full size Zorro 3 memory card that uses rare 30 pin memory and commanded high prices on the second hand market. The Fastlane has 16 30-pin SIMM sockets and can be expanded to 256 MB, but that would require 16 very rare 16 MB 30-pin SIMM memory. Phase 5 made awesome hardware back in the day but time marches on.

While the Fastlane was also a SCSI card the GottaGoFaZt3r is just a memory card. Where the Fastlane is full size the modern card is a mini half size Zorro 3 card. It is autodetected and just does one thing, adding more memory to your Z3 Amiga.

Whats the point of a 256 MB memory card in an Amiga?

The GottaGoFaZt3r can be built to be a 128 MB card or 256 MB card. Off course I went for the 256 MB option. While this could be seen as just bragging rights to be able to pump up your Amiga with a 256 MB memory card, keep in mind that this is actually usable on an Amiga, even with oldschool applications thanks to being able to use the memory card as a huge RAM disk.

Some comments about building the GottaGoFaZt3r Amiga memory card

Memory and CPLD was sourced from China, other than those parts its a very straight forward BOM. The build is also very simple. While the BOM does not mentions a capacitor at C1 I got the recommendations to add one so thats what I did.

My setup

In total there is 660 MB Fast RAM in my Amiga 4000TX

I installed the GottaGoFaZt3r card in my A4000TX. Currently the memory setup looks like this on my Amiga 4000TX which is alsy my primary Amiga.

  • GottaGoFaZt3r: 256 MB
  • BFG9060: 128 MB
  • ZZ9000: 256 MB

I will add 128 MB fast ram to the motherboard (which will be used as 96 MB by the A4000TX), so in the future I will have 736 MB fast mem in my daily driver. Currently the memory is reported as 660 MB as I have a memory stick that is not really supported by the TX so it only partially works.

Another Mini version of GBAPII++ built and tested

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I got the opportunity last year during fall to purchase a GBAPII++ mini graphics card with all passives already mounted. Only thing it did not have was the Cirrus Logic chip, memory chp and the CPLD (and some small components). The mini version of the GBAPII++ is the same card functionality wise as the regular one. You can read about the regular GBAPII++ here, you can read about the mini version of the card here.

As I was going to build the regular version of the graphics card in parallell I got lazy when I put together the BOM and assumed that the voltage regulator was the same for both of the cards. I was wrong, the GBAPII++ mini uses another voltage regulator, which explains why I could not program the CPLD and why the voltage regulator was running very hot on the card once I had built it.

Having received another shipment of components from Mouser late last year in December with the correct voltage regulator, I was anxious to find out if I had fried the card or if it was going to work. Happy to tell you the card in the picture is working fine after I swapped the voltage regulator to the correct one!

Whats the point of such a small Amiga graphics card?

I use my other GBAP2++ mini card in my Mini-ITX Amiga Denise but I think I will use this one in another big box Amiga. As you can see the Denise is installed in a very low profile case – The tiny card makes it possible to use a small case. If anyone is wondering what case I am running, it is a Chieftec IX-01B Mini-ITX case but it has the CD/DVD addition stacked on top of it to make room for the graphics card (Chieftec MK-35DV).

This Amiga is based on the Denise Mini-ITX A500+ clone motherboard. It has a TF356 68030 turbo card with 64MB memory, a 4 GB CF card and an Indivision ECS MK3, it also has a GBAP2++ mini graphics card. The video output from the VGA connector is beautifully switched from native ECS to P96 output (and vice versa).

Here is another closeup of the card running fine in my Denise Amiga clone.

OpenA1200RTC – Amiga real time clock built

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The final Amiga hardware project of the year for me is this nice mini hardware kit for the Amiga 1200, the OpenA1200RTC. A real time clock that you can hook up to an Amiga that has a clock port. Find out more about the OpenA1200RTC here. The real time clock makes the Amiga 1200 keep track of time.

Building the OpenA1200RTC

This was a very simple 20 minute build containing only 13 parts. The only moderately difficult to find part is probably the RTC chip which can be found on Ebay or AliExpress.

What is the clock port in an Amiga?

The Amiga 1200 has a port fameously dubbed the ”clock port”. The clock port is a 2 mm double row 22 pin header close to the CPU slot. It was rarely used for its intended purpose, to host a real time clock, since hardware engineers figured out how to hook up sound cards, serial ports and other things to it.

There are some Zorro cards that also has clock ports. That means it is possible to run clock port hardware on a big box Amiga that can carry Zorro cards.

So what do you use an RTC for anyways on an Amiga?

The main purpose of having an RTC such as the OpenA1200RTC is for the Amiga to not lose time when it is powered off. Having your computer keep track on time is not only usable for having a clock on the desktop. If the computer keeps track of time, that means all files will have timestamps whjen they where created or last edited. While it is possible to sync date and time with a server over the internet it could be handy to have an internal RTC on an Amiga that is not hooked up to the internet a majority of time. Also, it could be nice to finally use the clock port for its intended application once.

BFG9060 Amiga 060 turbo card in PCB color red fully built and tested

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BFG9060 with rev 1 68060 under testing in my A4000TX

I built a BFG9060 060 turbo card last year that I could clock at 100Mhz, this is the second BFG9060 I have built and it is in a cool red PCB color. Thanks to the Xilinx programmer I got I could finally program the CPLDs on it but did not have time testing it fully. Now that I have tested it I can finally confirm that it is working 100%.

Actually, I just ran Quake for an hour with it mounted in my primary Amiga, my A4000TX daily driver, and the card performed just fine. Once I have it permanently installed in one of my big box Amigas I will do a proper 24h POVRay fish render test. But as it is now, I am happy with how it performed!

Mystery 68060 CPU

I got this 68060 chip from Vesalia years ago (probably 12+ years ago), and for a really good price too. It was a deal too good to pass on even though I did not know what to do with it. Well I am happy that I kept it but for all these years I wondered three things:

  1. Did it work?
  2. What kind of 060 was it?
  3. Is it a fake? Why did it have these strange markings and not the typical Motorola markings?

The answer to those questions are:

  1. Yes the 68060 works fine! And it does not get that hot either (though I have a heatsink/fan on it).
  2. It is a rev 1 68060.
  3. It is not a fake 060 – It came from a Phase 5 turbo card – Phase 5 used to add this text to the 060s on the turbo cards.

While the CPU works, it is a little bit of a bummer that it is a rev 1 as that revision has bugs. But there are work arounds for that so it does not really matter. Unfortunately, as its rev 1, that means no 100Mhz overclock. But to be honest with you, I am glad just having another full (MMU/FPU) 060 on a big box Amiga turbo card.

68060 low profile 5v cooler

I was afraid that the CPU I had was going to run too hot so I went into my stash of heatsinks to look for a suitable cooler for it. I found this thin 5v laptop cooler that I must have kept in my stash for more than 15 years. I got it from an old Acer Celeron laptop I found in the trash at a job I had and I was glad I finally found a use for it.

It is a thin radial fan that sits on an aluminium bottom plate that acts as a heatsink. I have not found modern alternatives in this size for a good price so I guess they have become rare these days.

I used thermal adhesive tape (also called ”frag tape” BITD) to secure the heatsink to the CPU. Believe me, this thermal double sided adhesive tape has insane stickiness, there is no chance of the heatsink falling of the CPU if mounted vertically.

I can confirm, according to tests done with my finger, that the CPU does not run hot at all with the heatsink/fan on it. I am starting to wonder that maybe it was overkill, but if I end up using it in an A3000D case it might come in handy as that case has poor cooling performance.

A500-GraKa GBAPII++ Amiga Graphics Card built and tested

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GBAPII++ Amiga graphics card

This is the second GBAPII++ Amiga graphics card I have built. I finished the last bit of the build two weeks ago. Today I tested it in my Denise Amiga clone and could confirm that it was working fine. If you are interesting in building one yourself, check out more information about the graphics card here. There are some details about the background of the card there too.

Hardware specs

The GBAPII++ is a Zorro 2 based Amiga graphics card based around the Cirrus Logic GD5434 chip. It has 2 MB memory and is a relatively affordable Amiga graphics card. Occasionally you see users referring to the card as an open Picasso 2 card as you can order empty PCBs yourself and build it. But if you know Amiga hardware well this card is based on another chip. The similarities are close though, both cards has only 2 MB and is probably likewise in performance as they are both Zorro 2.

The VGA adapter plate has both output and input so its possible to run scandoubler output through one VGA output, very handy and a must have these days IMHO. I use mine with a Indivision MK3 and it works perfectly out of box. Or run it with the Multivision-AGA scandoubler.

It is possible to use the card on an Amiga 500 by soldering an 86 pin 2.54mm edge card slot to the side of the card, thats probably why the graphics card goes by the name A500-GraKa.

Components

The graphics card is based on the Cirrus Logic GD5434 chip

If you are thinking about building one I suggest you go looking for a GD5434 chip first. These chips are not impossible to find but can be pricey. I have paid between 20 to 40 euro each for Cirrus Logic GD5434 chips (currently have built four cards based on this chip). Finding an old VGA card and desoldering a chip with hot air is also a possibility.

The memory used is the same type of memory that is used in an Amiga 1200 1.4d revision. The typical SOJ40 2MB memory chips in the quantity of 4 chips.

I had difficulty finding the correct voltage crystal but eventually found the right one on AliExpress (and it worked too).

Building the graphics card

For some reason I thought building this card was incredibly confusing. I think the main reason is that I somehow got the build instructions for a previous revision of the A500GraKa card, once I got the correct file everything worked out fine! IIRC there are some solder pads marked as ferrite beads that should take resistors (or it was the other way). To find out what components go where one can look into the designer files, also study the BOM.

Performance

The graphics card works especially fine in lower resolutions and fewer colors like this 800×600 8 color Workbench

I have not tested performance yet and will probably never do, but make no mistake, this is no competition for a ZZ9000 graphics card. It is a fine card to use on a 030 based Amiga with a Zorro 2 bus as long as one do not go crazy on the amount of colors or resolution used. It is much better than using hires laced. I stick to 800×600 in 8 colors and it works fine.

Conclusion

The graphics card is hooked up to the VGA adapter plate that is fitted to a3D printed bracket

Many thanks for the creators of this card and previous cards it is based on. I think this card is a no brainer, just get one if you have an empty Zorro slot and no graphics card. I will list the good things first and negative later, these are strictly my personal opinions.

Positive

  • Half size card
  • Has a hole cut out for your finger so you can remove it easely
  • Autoswitch between scandoubler/VGA
  • Open card, PCBs can be ordered by yourself. There is also commercial version of it
  • There is a thread on a1k.org where you can ask questions about the card
  • Supported in P96 (so you can install the card with the P96 installer)

Negative

  • Somewhat confusing build instructions
  • Only has 2 MB
  • Is a Zorro 2 card so its slow (but still perfectly fine for lower resolutions/fewer colors)
Here is Doom running on the GBAPII++ Amiga Graphics Card

Finished building the Prometheus-Resurrector Amiga PCI board but could not program it

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I finished building the Prometheus-Resurrector PCI Amiga daughter board. If you where around 20 years ago you might remember PCI slots being the latest thing to add to your Amiga computer. It was as de-rigueur upgrading your Amiga to PCI slots as hacking your Amiga 1200 into a tower as tall as a kitchen table.

What is the Prometheus-Resurrector?

Prometheus-Resurrector is based on the Prometheus PCI daughter board from 20 years ago. If you are familiar you might know about the Firebird PCI daughter board for Amiga 4000 and Amiga 3000, they are sort of related. One difference between Prometheus-Resurrector and the original Prometheus is that this one is using Xilinx chips for CPLDs instead of rare, hard to find, Altera chips. Also, you can order PCBs yourself and build it.

The Prometheus slots into a Zorro 3 slot, then you have to be creative in how you mount the PCI cards as the cards sits 90 degrees from Zorro cards. Either you use PCI extenders or 90 degree PCI angle converters or just run them as is with extension cables to the backside of the Amiga chassi. No matter what option you chose, your Amiga, decked out with PCI cards, will look refreshingly hacked together just like all those towers-hacks looked like back in the day. How nostalgic.

Programing the Prometheus-Resurrector

Unfortunately the story, for this time, ends here as I got the wrong programmer from AliExpress. I failed to program both CPLDs with my trusty Raspberry Pi so I got this nice Xilinx programmer, totally offical (not), from China. However that did not help me program the chips, I think I got the wrong one. So until I get the other Xilinx programmer I ordered, the story ends here.

To be continued!

Replica A4091 SCSI card

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Today I got a fully built replica A4091 Zorro 3 SCSI card delivered. The A4091 was a SCSI 2 controller for the Zorro 3 slot, it was made by Commodore. This is a reverse enginered version that you can find prebuilt on the internet or build yourself. Find out more about the original C= 4091 card here and the new replica A4091 SCSI card here.

I watched the presentation of this card on an Amiwest stream a couple of years ago so its exciting to have the real card in my hands.

Advantages of SCSI in an Amiga

The advantage of using a SCSI harddrive and a A4091 in a Zorro 3 Amiga is that it will have faster transfer speeds than IDE. SCSI is also less heavy on the system as the card has its own brain to process file transfers taking up less CPU time than IDE. This is good as Amiga is limited in CPU power (at least with a real CPU).

Zorro 3 only!

This card only works on the Zorro 3 slot. That is good news since it means better performance than a Zorro 2 card/slot. But it also means it will only work on the A4000(T) and the A3000(T). The Amiga 3000 already has SCSI on the motherboard, but if that does not work well, this card could be the solution.

Hardware setup

This card will probably end up in my A4000TX or in my A4000D. The A4000T already has SCSI2 and is basically the A4091 card implemented on the motherboard (well, the main chip is the same). As my main systems already got 060s, graphics cards and plenty of memory this is a welcome addition in squeezing out the last performance before I go into the world of PiStorms.

I will run a ZuluSCSI card on mine as I have banished mechanical harddrives from all my computers. The ZuluSCSI can emulate multiple harddrives (and CDs) stored as files on an SD card.

Purple Amiga A4091 SCSI 2 card

And I actually lied a little when I said that it was exciting to finally have the card in my hands as I already built a purple A4091 SCSI 2 card last year.

New incoming Amiga PCB projects

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Here are some new Amiga PCBs for some new projects I got this week:

  • GottaGoFaZt3r memory card (will do the 256 MB version and probably a second card).
  • PiStorm16 x 2
  • Prometheus clone
  • MpegIt for the Prelude Amiga sound card
  • Prelude sound card PCB (not in the picture)

I also have two Amiga graphics cards in my todo list:

  • GBAPII++ graphics card
  • Mini GBAPII++ graphics card

And lets not forget the ReAmiga 3000 PCB I got late this week too! I have had a broken Amiga 3000D motherboard in my stash for years so finally I will be able to shake some life into it again!

So lets just say a massive BOM will be ordered soon!