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

GBAPII++ Amiga graphics card

This is the second GBAPII++ Amiga graphics card I have built. I finished the last bit two weeks ago. Today I tested it in my Denise and I confirmed 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)

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

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

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

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!

Amiga 4000D front LEDs

Here is my black Amiga 4000D with a green power LED

I bought a replica Amiga 4000D case off of Amibay earlier this year. One of the joys of building and buying clones and replica hardware is the challenge of finding parts you need. In this case, I needed a front for the A4000D. Thankfully there was 3D model you could download and 3D print that solved the problem, but it did not came with LEDs or the keylock so here came another challenge: find the correct parts for the LED, how to mount them and where to find the keylock.

Amiga 4000D LEDs

Amiga 4000D front panel LED

So the LEDs are standard square, flat 5v LEDs. These can be found in most electronic shops, here is a link to the green ones I bought. I think green looks fine, there was yellow and orange also and probably blue if you look around. I am not that fond of blue leds so green was it.

A4000D uses a two pin Molex connector and a flat LED

The LEDs are mounted to two terminal Molex connector (2.54mm). The Molex connector slips into the opening over the cable sleeves. If I remember correctly this is actually how they are setup on a genuine A4000D. On the picture above you can see the long pins of the LED sticking out through the back of the Molex connector, I cut these off and bent them over the Molex connector afterwards.

There are magnets on the back of the A4000D front that holds it to the chassi.

Here you can see the 2 pin Molex connector placed into the holes for the LED. On an older A4000D I had (a genuine one) I put a dab of hot glue on them to hold them in place, perhaps I will do it on this A4000D replica too in the future, but for the moment they stay fit on the A4000D front with no problem. You can also see the cables, they are soldered to three pin 2.54mm connectors. One pin is left out.

Cables are inserted to the A4000D motherboard

At first the LEDs did not light up, so I just switched positions on the cables and then they worked as they should. If you look at the A4000D motherboard circuit to the pinouts, you can see that the middle pin is unique, but the two outher pins are the same (hooked up together). So if you have the correct polarity you can flip them around and they should work.

Amiga 4000D keylock

Amiga 4000D front with keylock

The Mouser part number for the keylock is, 612-KO132A1501 – here is the page for it on Mouser. If I remember correctly the keylock does not disable the A4000D from working, it just disables the keyboard. And to be totally honest, a keylock in this day and age is kind of pointless, however the A4000D front would not look correct without one, so I ”had” to get one. I just soldered two wires to the terminals of the keylock and hooked it up to the motherboard.

Got my ZZ9000AX Amiga sound card running

The ZZ9000AX Amiga sound card for the ZZ9000 graphics card

There is a sound card for the ZZ9000 Amiga graphics card called the ZZ9000AX. It is a small soundcard that is attached directly to the graphics card.

I had some problems with the ZZ9000AX

Keep in mind that I am running the card on an unofficial Amiga motherboard so that might be the case (A4000TX) and not the fault of the soundcard.

I got one of the soundcards last year but had massive problems getting it running well. The ZZ9000AX seemed to be picking up noise off the buss and many times had a disturbingly loud background buzz that never stopped. Paula sound is passed through the ZZ9000AX and when Paula output was passed through the ZZ9000AX it just sounded horrible. Sometimes distorted, sometimes just totally wrong, so far from the regular crystal clear Amiga sound output I was used to.

I was sent a replacement card from MNT but it did not fix the problems, just introduced different sounding problems. I am not blaming MNT for these problems – as I was running it in my A4000TX which is a non standard Amiga model (with no public schematics), there might be some kind of difference between an A4000D CR and an A4000TX that introduces these problems into the audio output. Without schematics it is not possible to go further investigating the problem. I am going to test my card on my other Zorro machines in the future to find out if it is the fault of the A4000TX or not (will update this text). But the card was sadly unusable for me in my A4000TX.

Finding a solution

ZZ9000AX with external to internal cable

Playing around with the card I noticed that if I removed the three wire cable that connected Paula audio output into the ZZ9000AX (you can see it attached to the card above) the card was beautifully silent, no bus noise, no irritating static and no weird noises. Playing MP3s worked fine. So I got an idea to remove the three cable wire and route the output from the ZZ9000AX into the Paula input header so the output of the soundcard was mixed into the sound jack of the A4000TX.

Cable in detail, it is just a simple cable, nothing special to be honest

I created this little cable just to prove if it could work. I will make a nicer looking cable in the future. The A4000D and the A4000TX (that is based on the A4000D CR) has a audio in input on the motherboard, likely for CD-ROM input or for AV purposes.

It is connected to line in on the A4000TX motherboard so it gets mixed into the output for the sound socket.

You can see the cable connected to the audio input header on the image above. It is a messy setup, but the system is in a state of work in progress at the moment.

The cable is just a nasty quick hack, I will do something better here in the future

Here is the backside of the A4000TX and how I route the cables to the internal audio input. No doubt I will create a more neat solution in the future, but for now this will do.

Does the fix work?

Yes it does, I have configured AmigaAMP to use the MHI drivers for MP3 playback. Both MHI and AHI works fine. There is no bus noise and no ringing noises in the background. The sound output is dead silent when Paula is not creating sound or an MP3 is not playing, just as I expect it to be. And best of all, playing modules in an module player sounds crystal clear. Playing MP3s on my Amiga sounds just as they do on my PC now!

New project inoming: Mini version of GBAPII++ Amiga graphics card

Today I picked up a small parcel that was sent to me, the parcel contained a GBAPII++ mini Amiga graphics card PCB. The GBAPII++ is a half size Zorro 2 Amiga graphics card based on the Cirrus Logic GD5434 chip, you can read all about that project here. This is a smaller version of that card – It is intended to be used with the Denise A500+ clone (Mini-ITX) but can be used on all Amiga systems with Zorro slots. You can read all about the mini version of the graphics card here.

Specification of the GBAPII++ card

This is a Zorro 2 card, it has 2 MB memory and is comparable with the Picasso 2 graphics card in performance (give or take performance in some tests). It is a perfect match for Z2 and 030+ systems IMHO but is not really a competitor with the zz9000 regarding performance (in a Zorro 3 system).

Lets take a look at the GBAPII++ card

Front side of the GBAPII++ Amiga Zorro 2 graphics card

Usually I prefer to build projects from scratch but in this case I did not mind a version where the passives where already pre-installed. The GBAPII++ mini version uses mostly 0603 component sizes. That is 1.6 x 0.8 mm in size, not impossible to solder, and to be honest not that challenging, just very tedious. Especially if you do not have a proper workshop with microscope.

Here is the back of the graphics card, not much happening just some 0603 parts

The missing components are 2 MB memory consisting of four chips, SOJ40 (this is the same memory type that is installed in an Amiga 1200 rev 1.4d). The card needs one CPLD, two ICs, crystal and the GD5434 chip. The Cirrus Logic chip can be taken from a PC graphics card. Occasionally NOS chips show up on Ebay from time to time. Expect to pay 25-40 euro for the graphics chip alone (and more for the full graphics card).

I also got this little VGA out PCB that hooks up to the graphics card and fits neatly at the back of the Denise Amiga 500+ clone.

3D printed Amiga 4000D front panel

I bought a replica Amiga 4000D case earlier this year on Amibay. It is really good clone of the A4000D case with the exception it has slightly better cooling, space for a 40 mm fan, was painted black, has some options the original Commodore A4000D did not have, uses an SFX ATX PSU and did not come with a front panel.

I really like the look of the A4000D (even if it is just a lousy PC case that was adapted to the A4000D in the last minute), especially the front panel. If there is a template for a professional early 90ies computer case, I think this could be one of them (together with SGI, Sparcstation and so on) – There is just something about the angled look of it and the Amiga logo inprinted in the case cover mold.

Functionality wise, the case is a disaster. The Amiga 4000D case has lousy cooling. The whole case depends on the fan in the PSU to cool the whole system. There is no active cooling at all on the Zorro board section. It has the mouse and joystick port awkwardly mounted on the side making it difficult to remove the cover. And while it has a 5.25 slot, it is too shallow and wont take a full length CD-rom (or DVD). Many of these problems has been solved in the replica case and many of these problems are not problems anymore (I never want to touch optical media again).

What about the A4000D 3D printed front panel?

Its a bit dusty in the picture but the finish is really smooth

The files for the 3D printed A4000D cover can be found here. You can find the different 5.25 and 3.5 cover slots there too. I got them printed at JLCPCB in nylon resin and something, I have forgotten, I also got the power button on a stick 3D printed. All in all the total cost was somewhere around 50 euro, very affordable IMHO. The front was printed in one piece. It has a bit of a rough look to it if you look close, but it is surprisingly well done. I do like the rough look as it resonates with the home built A4000D motherboard, its not perfect as in a factory made case/computer as it is DIY built.

However, the front panel do not fit on the A4000D case that good. The clips are too long and they are really soft and became slack quick, meaning the front panel hangs off the front of the case and just looks cheap.

How I got the Amiga 4000D 3D printed front panel attached to the case

I had an idea to use strong neodymium magnets to hold the front cover onto the A4000D case.

In the picture above you can see four round magnets and two banana shaped magnets. The banana shaped magnets came from an old 3.5″ harddrive that I recycled. These magnets are really strong.

The round magnets are also neodymium magnets but less strong. If I was to start over I would just use three of the really strong banana shaped magnets they hold the 3D printed front panel to the case strong and secure. See the peg in the bottom left corner and how it has sagged.

It looks a bit sloppy because it is, I will paint the stand offs for the magnets black and maybe even add some black bondo to them to make it look nicer. However as a proof of concept everything works and is secure. The stand offs are regular plastic pencils that I cut to lenght and then super glued to the 3D printed A4000D front, I then super glued the magnet to them and let everything dry over the night.

I thought that the magnets would work themself loose from being super glued to the stand offs but I have been proven wrong. They are secured to the stand offs and case and wont move or brake off.

Here is the case with the cover added to it, being held to the case just by the magnets. Taking it off the case needs a lot of force. To make it easier I sanded off the hooks on the pegs of the front cover to make it easier to slide out the holes of the front of the case. Again, looks rough but works fine.

Here is a closeup of the 3D printed A4000D front cover, the badge was bought from a store online.

All in all I am very happy with my black A4000D case. I think it fits into a modern office much better when it is black as so few computers come in beige these days.

Amiga 4000D maintenance

I have an Amiga 4000D that is in a work in progress state. I am in no rush to get it finished and I enjoy the process of setting it up. It is an Acill A4000D motherboard that built last year. It has a Firebird PCI daughter card, a MicroniK scandoubler and a C= 030 CPU card. Everything is mounted in a replica black A4000D case with a 3D printed A4000D front (incl. covers). Final state of this Amiga 4000 will probably look a lot different but for testing purposes, this will be fine.

Adding a IDE-CF interface to the Amiga 4000D

Today I added a slot bracket mounted Compact Flash card adapter to it so I could test out a couple of 72-pin SIMM slots. I do not have a floppy drive in most of my Amigas so I had to run Workbench of off a CF card to be able to see total memory. Thankfully I still have old school 40 pin IDE cables in my parts stash.

I used the Workbench installation from my Denise ITX Amiga 500+ clone by simply borrowing the CF card from it. I will post some more info on this beautiful little Amiga computer later sometimes.

With the CF card inserted in the Compact flash adapter my A4000D booted happily of off the WB 3.1 installation on the CF card. Having the CF card accessible from the outside of the Amiga is a must. I often find myself mounting the CF card in WinUAE to take backups and to install and transfer software.

Testing 72 pin SIMM memory

The first thing I wanted to do was to remove the 32 MB SIMM I was using in the Chip memory socket and replace it with a genuine 2 MB SIMM. All fine, the 2 MB 72 pin SIMM worked fine as chip mem! 2 MB 72 pin SIMM memory is getting more difficult to find these days unfortunately – hopefully there will be more DIY options in the future.

The A4000D supports up to 16 MB fast memory on the motherboard, either through four 4 MB memory modules or through two 8 MB memory modules. You can see that I built the A4000D motherboard with only two 72 pin sockets for fast memory, so I need two 8 MB modules to get 16 MB.

Unfortunately, I did not have any 8 MB SIMM memory (all I had was 16 and 32 MB modules) so the maximum memory I could add was 4 MB (one 16 MB SIMM becomes 2 MB in the socket). 72 pin memory modules rarely indicated memory size so it was necessary to test them in a computer. Now this is not really a problem since I will be running either a BFG9060 or a TF 060 card in this computer. But it is always nice to max out memory if it is possible to so.

Conclusion

  • I added a new thing to my todo list, find some 8 MB SIMMs.
  • I also flagged some things on the todo list as finished, CF card adapter + chip mem is working.

n2630 68030/Memory/IDE card for the Amiga 2000 (EATX)

I built my second Amiga 2000 EATX last year, it is a beautiful clone of the Amiga 2000 remade into a standard extended ATX format so it can fit a standard EATX case. You can be sure that I will add an article about that motherboard here in the future. The author of that project has also made the n2630 project, its a clone/reimplementation of Commodores 030 card for the A2000, the Commodore A2630.

To be honest, I wish there was a modern 060 or 040 card we could build for the A2000 since I think 030 is just too slow these days – at least for my modern Amiga standards. To be fair while the A2630 was 25 Mhz this one runs at 50 Mhz, so its a little bit faster. 040 runs so hot, but would be a perfect fit for the A2000EATX because of the improved case airflow (and having an 040 in one of my machines could be interesting to compare performance with 060 machines).

Anyways, I should be glad with what I have and I am thankful that we can build this cool modern 030 card for our A2000 computers. And the n2630 is such a nice compliment to the A2000 EATX motherboard having IDE/CF slot built in.

Building the n2630 for my A2000EATX

I decided to build my n2630 card earlier this year with 128 MB fast memory. There was an option to go for 256 MB fast memory also but thought it was not really worth it, maybe I will regret it in the future. Otherwise this build was very straight forward. It uses three CPLDs and six memory chips.

There was some parts that was difficult to find, first it was the 030 CPU socket. I actually got the parts number for one that was availble on Mouser after asking around, surprised about that. The CF slot at the back of the card needs to be the right one to fit solder points on the board, ask on the Discord if you wondering what type you should get if you are building one. Other than that it was an easy build. There are also two eproms you need to have and program, but as usual, most stuff that is rare can be found with some patience.

I have since mounted an FPU to the card and I also got a 3D printed bracket so I could secure it in my regular ATX tower that was converted to EATX. I ran out of black pin stripes that is why I used yellow and green (it was also a joke about obsessing over the color syncing of hardware).