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.
