Things have been a bit quiet recently as we have been going through the stressful process of moving house. But we are now in, and work has started on the new home of north devon retro archive!
I would by lying if I didn’t say one of the biggest reasons I picked this house, was because of the self contained 31ft long basement workshop. This will give me more room to setup my collection exactly how I want it.
Anyway, today was the first day I got to do some work in there to start making it the area I want it to be.
So here is a sneak peak of the room before and after today’s DIY session. More pictures will come as the space progresses.
After a trip down to the South West Amiga Group’s latest meet on Saturday, I strangely enough ended up returning home with an Acorn Archimedes A3010. The computer was labelled as non-working and I paid the sum of £50 for the privilege of bringing it home with me.
These computers are notorious for being destroyed by their onboard batteries. Thankfully the previous owner had already cut the battery out and cleaned the board, but then didn’t get any further with the repair.
I don’t class myself as an Acorn expert by any means, but I have done a lot of reading up on the Acorn machines in the past from when I repaired my RISC PC. From my previous repair, I also have an Acorn “POST Box” which is a little USB board that connects to the diagnostic port on 32bit Acorns and gets some extra diagnostic details from the machine.
Upon connecting up the board, I could see a RAM error message with the code 0000FFFF. These error messages are actually in Hexadecimal and therefore translated as 00000000000000001111111111111111 in binary. Indicating that the highest 16 bits of RAM were fine, but the lowest 16 bits were not working. The A3010 has two RAM chips on board and the one furthest to the right is responsible for the low bits.
After grabbing my multimeter and the schematics for the board, I probed all the pins and found the RAS line was not connected (RAS and CAS are used for selecting the Row and Column of memory to be read) and neither were 6 other pins. So my first repair was re-linking these traces. Some I just soldered on top of the board and some I used fine wire from the memory chip to the vias on the bottom of the board.
After this, I had a booting computer but quickly noticed the mouse wasn’t working. Using my oscilloscope I probed the LS241 buffer chip on the board that deals with the mouse signals. All signals looked fine going into the input pins on the chip apart from one bad trace, but there were no output signals at all. Luckily I have a spare donor board for the RISC PC which uses the same chip, so a quick transplant and another wire repair got the mouse back up and running.
Almost there, but one last problem was that the floppy disk drive not working correctly, it would initialise but then return an error saying “Drive Empty”. After doing a bit more research I found that the A3010 used pin 34 on the floppy to determine if there is a disk in the drive. I probed all of the pins and they all had connectivity to the controller chip. But most of the floppy control pins are pulled high to 5v via a resistor. I checked pin 34 and the signal was permanently low.
Further inspection revealed that the trace going to the pull-up resistor was broken. The same issue was affecting the index pin also (Pin 8). With both of these now repaired, the floppy drive came to life and I now have a fully working Archimedes.
Gotta say I’m pretty happy with how that repair went. And what better way to celebrate, than a quick game of Lemmings!
I know I’ve been a bit quiet for a few months but I have been working on a big project in the background (More info soon).
To keep me busy though, I decided I needed something new to have a tinker with, so I purchased a non working Apple Macintosh Classic II off Ebay.
The seller did a great job of packaging it up and it arrived with no damage whatsoever. I tried powering it up and got vertical lines on the CRT just as the eBay listing showed.
Interestingly, on my 3rd or 4th power on, I heard the startup sound and the machine booted straight up. The hard disk was working fine and so was the floppy drive!
Not exactly the repair challenge I was hoping for, but I can’t complain.
I have since re-capped the logic board, although to be fair it was in near-perfect condition, no corrosion, and even the battery had no leakage.
Even after the re-cap though, it suffers from an issue where when powered on, it will stay on a black screen, and after 10-20 seconds it will then spring into life. I’ve noticed this start time has decreased in the warm weather.
I am expecting it to be the capacitors on the Analog board that need replacing. I don’t have all the correct values here currently though, so will sort that another day.
I am also just about to acquire a SCSI Zip drive, so once I get that I can use my PC with Zip drive to transfer some software across and have a proper play.
Ok, so I actually bought a 2DS quite a while ago and forgot to add it to my list. So when a cheap boxed 2DS came up for sale I picked it up. Only afterward did I start getting deja vu and realised there was one sitting on display in my cabinet lol.
It did however motivate me to start messing around with it again and I have spent a fair amount of time playing with the 2DS’s best use case, A ZX Spectrum Emualtor! ZXDS is in my opinion one of the best ways of playing Spectrum games on the go. The 2DS form factor is great and the second screen acts as the keyboard for the Speccy.
To run the emulator you will need to have hacked for 2DS which is a pretty simple process and you can follow the guide at https://3ds.hacks.guide/
Once you have got that far, download the emulator from this website: http://zxds.raxoft.cz/
In the zip file, you will need to copy the entire ZXDS folder and place it in the root of your 2DS SD Card. Also, copy over the .cia file.
Then put the SD card back into your 2DS, load up the FBI application and use it to install the .cia file. It should now appear as a new app on your 2DS and you are good to go.
You don’t even need to worry about games as it has an online capability to download games directly from the World of Spectrum archive. Although some games such as ones made by Codemasters, you will need to find elsewhere due to copyright issues.
And there you have it, a portable Spectrum that is much better than any of the other attempts at a handheld Speccy (and cheaper!)
I will also mention that there is a great C64 and Amiga Emulator, but these run better on the “New 3DS/2DS” consoles.
As anyone who has looked through this website is probably aware, I like to modify my old hardware to add modern features to them, especially when it comes to loading games.
I have several “Everdrive” type devices connected to my cartridge consoles and many ODE (Optical Drive Emualtors) for my disc-based consoles such as the PlayStation and Dreamcast.
One console that has been missing a solution for me though has been the 3DO FZ-1. There are a few different options available on the market for this console, but mostly, they cost upwards of £200. This is obviously cheaper than buying all the original games, but the 3DO didn’t exactly have an amazing software lineup so I struggled to justify the initial outlay.
That is until I discovered an open-source project for a 3DO ODE named SataTo3DO which uses the Raspberry Pi Pico to do all the hard work. Whilst reading up on this I also discovered a remix of it which was a more compact design using some surface mount components which can be found here.
I quick visit to JLPCB and RS-Components, and the parts were all on their way to me. Whilst waiting, I also decided to 3D print a front panel for the console allowing me to fit a USB connector to the front without destroying the original console and trying to keep the original aesthetic.
All together the ODE cost me around £20 to put together and has so far played everything I have thrown at it. It is also another great usage of the Pi Pico which is seeing itself used in more and more retro projects recently.
Hopefully, in the future, we will see more open-source projects coming along for this type of use case. An open-source Sega Saturn ODE would be next on my wish list 🙂
Anyway, I will leave you all with a picture of the console re-assembled. I think it turned out quite well.
Since getting the Quest 3 on launch day, I really wanted to have a mess around with the new mixed reality feature. So I installed Unity and started to re-familiarise myself with it as it’s been a while since I last used it.
After searching around for a while, I found an open-source Gameboy Emulator plugin for Unity, it isn’t the best emulator and has a lot of compatibility issues, but for a quick project, it would do the job! (https://github.com/KonsomeJona/UnityGB). So with the emulation out of the way, all I had to do was sort out the mixed reality passthrough and controls etc.
So after several hours of messing around, I finally put together a mixed reality Gameboy Emulator.
If you want to give it a try you can download it from HERE
You will need to have enabled developer mode on your Quest 3, then extract and sideload the APK file using SideQuest.
Once installed you can copy Gameboy ROMs to your Quest by plugging it into your PC and copying the .gb files to \Quest 3\Internal shared storage\Android\data\com.northdevonretroarchive.GameboyMR\files\
There is a weird bug at the moment where occasionally the controls don’t always respond properly, if this happens then just restart the app. I haven’t looked into what is causing this yet, so I will update it once I have.
You can move the Gameboy around by grabbing it with the right controllers trigger button. You can also rescale the Gameboy by holding both grip buttons and moving the controllers away from each other. This allows you to play on a 50m tall Gameboy if you so wish!
One of the most obvious Amigas missing from my collection was the Amiga A1200. I already have a CD32 with a TF330 card so this was my alternative to the A1200, but I decided that I needed to get the real experience.
So here it is, a lovely condition A1200 with 4MB of additional memory in the trapdoor and a compact flash card adapter mounted on the back to replace the 20 MB HDD that was fitted.
I have also moved my PCMCIA Network adapter to this machine and hooked it up to an ethernet to Wi-Fi adapter to connect it to my home network for internet access and transferring files.
Apart from a few creature comforts, I am keeping this one close to original including the floppy drive so I can load that original Amiga software.
When I first heard about the Analogue Pocket, I thought it looked like a nice device, but I didn’t commit myself to a pre-order. I already have several emulation handhelds that can play pretty much anything I want them to.
But, as time passed, I started seeing more reviews of the device saying that it really was a nice piece of hardware, especially with the 1600×1440 3.5inch screen (which perfectly scales for the Gameboys resolution).
When the device was first launched, the main limiting factor was that it only played original Gameboy/Colour/Advance games with an optional adapters for Game Gear/Lynx/TG16 advertised. This is great for people that have large collections of original games, but I didn’t really fit into that category.
Fast forward to today, and the story is completely different. The Analogue Pocket has now been opened up to the community for development, and many FPGA Cores have now been released for the system that allow rom files to be loaded from the SD-Card. The device now supports the majority of 8/16bit consoles, some arcade machines and even the Amiga (Seen running in the screenshot above).
The system has become a very nice device to play on and has a great community building around it. I’m looking forward to seeing what other systems get ported over to it in the future.
These days Everdrive cartridges are the easiest way of transferring ROM files over to the N64. But this wasn’t always the case. Back in the late 90s, a company named Bung Enterprises Limited released its Doctor V64 device. This device was marketed originally as an N64 dev kit, and some companies did actually use it as such since it was much cheaper than the official developer kit. The device could also be used as a standalone CD/Video CD Player. But the general consumer of this product was more interested in the ability to modify the device, then dump official cartridges and load the ROM files back to the N64 from CD-ROM.
Nintendo wasn’t very happy about this feature of the device and as you can imagine, law suites soon followed. Over in America Nintendo managed to get the product banned from sale. This didn’t stop Bung, and they continued to sell the device in North America by advertising it simply as a Video CD player and not mentioning its additional features.
Using the device is pretty simple, you sit your N64 on top of it so it connects via the external port on the bottom of the N64. Next, you turn on the V64 and load a CDROM with N64 ROMs into the drive. You can then select one of your ROM files and it will load it into the V64 memory (256mbit is installed in mine). Now you can power on the N64 and it will load the ROM straight from the memory of the V64.
There is one additional part needed, an original game. Since the N64 had copy protection via a CIC chip on the cartridges. The V64 came with an adapter that sat between the N64 and the original game, this adapter simply blocked the original game from booting so the only thing that happened in the CIC chip activated and then waited for the game to boot from the V64.
My V64 was missing this adapter, but any original game could be modified by cutting one of the tracks to prevent the actual game from booting. This is quite handy as it doesn’t take up as much space as the adapter and a fully cased game, so it fitted in my IKEA shelving much easier.
I’ve been fairly busy recently and even though I’ve still been doing a lot of stuff with retro hardware, I’ve not found time to update this site. So I need to catch up, starting with this one which I have actually had for over a year but I knew it wasn’t working so has been sat in my pile of things to fix.
This is the Acorn Risc PC600. As with nearly all of these units, it came into my hands with battery damage. The leak was pretty bad, so the first step was to cut the battery off and clean it all up.
I then purchased an Acorn POST box interface which would allow me to easily read the power on self-test error messages on startup. Upon powering it on it showed that the CMOS was unreadable and it had sirq and virq errors (Sound and Video). Reading up on these it is usually caused by the buffer chip and the resistor network chip next to the battery, no longer being connected to the vidc chip. Using a multimeter I jotted down all the broken traces and re-joined them all.
Powering it back on whilst holding delete to reset the CMOS settings, the POST still gave a virq error and I was about to turn it off when it booted into RISC OS. At this moment in time I was pretty happy. There was still an issue but I had a functioning machine. I was able to test the HDD and the floppy both of which worked. It was then time to go back to my day job for a while, so left it there ready for me to come back later.
After work that day I went back into my workshop and the first thing I wanted to do was format a floppy disk. So I grabbed the mouse, clicked on the floppy drive and the screen went black. Powering it off and back on gave me nothing, and even POST wasn’t working now. After a few choice words were spoken, I started looking around and checking signals with the multimeter. It looked like the PC was being held in reset. These RISC PCs do something a bit unique when they are in reset where they do a count sequence on the address bus, therefore on a multimeter you see it where A0 will have a square wave at a certain frequency, then A1 will be half that frequency, A2, half again and so on. But I checked the reset signal and it looked like every other reset signal I had seen on 8-bit machines, goes high, then after around half a second, goes low.
Some head scratching followed, I expect some more swear words, then I read an Acorn technical manual that gave me the answer. The reset pin on these machines is actually active low! So the circuit was functioning, but the final output was the inverse of what it should have been. Checking the circuit diagram there was a not gate IC on the reset circuit that dealt with inverting the reset signal for the CPU. I ordered a new one and replaced it with the hope I would be back up and running again.
Well, this hope was soon dashed when I powered it back on. The system would POST now, so I had fixed that issue, but I still got the vidq error, followed by a red screen, and then at that point I lost all video output. So something was still wrong.
I spent quite some time going over every signal I could think of and they all looked ok, but by ok, I mean that the signals were there and doing something. What I didn’t know is if the signals were doing what they were meant to be doing. At this point, I decided to look at some other ways of getting this machine back running again.
I was fairly happy with the fact that all other components were working and there was just a board fault somewhere. So I managed to grab another Spares or Repairs board off eBay. This one looked in much better condition than mine so I was hopeful it would be an easier fix. When I got the new board I was again greeted with virq errors and also a DRAM error. I started going through each of the data bus pins to check that there were signals going to the vidc chip. I then noticed that two of the data bus signals seemed to be competing with each other and looked messed up. Confirmation of this issue was discovered when the helpful people over on the stardot forum explained that the DRAM error was actually a hex number and by translating that into binary it showed an issue with data lines 25 and 26.
Using a multimeter, I then discovered that D25 and D26 actually showed continuity between the two pins. The problem here is the data bus goes all over the motherboard so where was the short? I started easy and removed the ROM chips and the CPU, same issue. I then removed the buffer chips as these can go faulty, still the same issue. With only a couple of options left, one being the IOMD chip which was going to be practically impossible to replace, I removed the last easy component, one of the resistor network chips, at this point the short vanished! So I soldered everything else back in place, transplanted this IC from my other board, and finally a working RISC PC 600!
I am fairly happy with my repair as I do now have a functioning PC. But I think I am still going to have to go back and visit my other board. Now I have a functioning device I can see exactly what good signals should look like and can hopefully pinpoint the issue. I am fairly sure it’s going to be the data bus connection to the vidc chip, but the signals were all present, so now I need to look for ones that even though they are present, just don’t look like they are supposed to. I will post an update if I ever get to the bottom of the issue.
My next step is to start discovering what these machines are capable of. I have already swapped the drive out with am IDE to SD adapter and I think I would like to experiment with sticking a second processor in the unit. There is a board that allows a 486 processor to be inserted as a second CPU and then run DOS programs within a window in RISC OS, This sounds pretty neat and I do have a spare Blue Lightning 486 DX2-66 processor sat here wanting to be used.
Thanks go to Ian on the stardot forums for providing help through this repair and also building the Acorm POST box which proved very helpful.
