Plugging away at some things

Copyright 2020

Hi Intarwubs, it’s been a while, hasn’t it?

I’m not dead, I just don’t have much exciting news. I do have some projects that are “in progress” but nothing finished.

Projects

I’ve been working on a GBS Control install, but it’s not working quite right yet. I am yet to determine why. I need to do some more diagnostics before I work out what’s wrong with it. The EPS32 is responding fine, and seems to be controlling the GBS 8200 OK, I’m just not getting any scaling. Not yet sure why.

More work to do there.

I have been also working on a “Secret” project for the Creativision. Unfortunately I made a mistake on my first PCB and before I order a replacement PCB, I want to make sure there are no bugs in my schematic. I’ve bodged around the mistake but the design doesn’t seem to be working still, so I’m working with my collaborator on that one.

Systems

No new systems for a while. A friend (Hi Greg!) has offered to help get me a Macintosh SE/30 so I’m super grateful for that. That’ll be a fun system!

I’ve also been working with the people looking after my UK systems and hopefully I can get those sent over eventually, especially as I don’t see travel restrictions being lifted any time soon.

I probably should order my “Christmas Present” sooner rather than later. That way I’ll have it by some time around Christmas. πŸ˜€

Games

I have been playing some games. A certain cartridge I ordered for the N64 has arrived so I have been playing quite a bit of N64 gaming. Zelda: Ocarina of Time is still an excellent game.

Fixing the NES

Box ‘o’ NES, copyright 2020

So, for quite a while, I’ve wanted to get my Nintendo Entertainment System up and running. There are a lot of classic games for this system, and while emulation is now practically perfect, I still like the feel of original hardware. Besides, I now had three non working units.

By far and away the most common fault on the NES relates to a decision very early on in the design cycle of the unit to try and make it less “game console” like. (Thus the name doesn’t contain “game” or “console”). To this end, Nintendo made the system “front loading” to evoke the increasingly popular “VCR” units flooding the world. Unfortunately the connector that this system uses gets a LOT of wear and tear and is prone to failing. It’s a bad long term solution. (The Famicom, that the NES is directly based on, is a top loader like almost every console before and since, and thus avoids these problems). To make matters worse, the “standard” advice at the time was “blow on the cartridge and reinstall”. This did two things:

  1. Reinserted the cartridge, which is probably what was needed in the first place and
  2. Got a whole lot of corrosive spit in there with the delicate cartridge connector, making the problem worse.

I had replaced the cartridge connector on one of my machines already and got about 6 months of additional life out of it, I’d tried the “bending the pins” trick, and I’d even boiled the connector, but this was not a game I wanted to continue to play. I’d done my research and knew there WAS a better solution out there. It wasn’t too expensive, but once I’d added shipping, the price basically doubled. Oh well. Bite the bullet.

I bought an Arcadeworks BLW.

These are a complete rebuild of the entire cartridge slot of the NES, making it have a “top load” connector, but inserted sideways into the cartridge. I placed the order, after determining there is no no Australian distributor, and waited. And waited. And waited.

Arcadeworks had shipped practically the next business day, and my package was being tracked, so that I could see that it sat in LA for nearly a month. Another thing we can “thank” the current pandemic for. Eventually, after over a month, it finally arrived. (I’d contacted Arcadeworks after a month and they were responsive but couldn’t do much about it.)

So this weekend I dug out my box of opened NES and prepped and assembled the first NES. It. Didn’t. Work. Not a lockout issue, which would manifest as a flashing screen and a blinking power light. Just a grey screen with a lit power led and no further activity.

At this point I got up, ate dinner then came back. This machine had been reworked (by me) at one point and I was uncertain about the lockout chip at all. I knew it may have been killed in the process, so I put it aside and dug out the second NES.

Reassembly followed… and it worked! It was flashing that it was in “lockout” mode, but I was prepared for that. A power off and power on in quick succession programmed the BLW onboard chip to be a PAL system and we had video. Success!

The NES is now in my cabinet with all the other consoles. There seems to be an issue with sound, but that may be an issue with cabling. I’ll pull it out again in a few days and plug it into my test TV to double check. I have two “spare” units so I’m not too stressed. I figure, worst case, I’ll need to swap a sound chip. Best case it’s just a loose cable in the console setup somewhere.

Big thanks to Arcadeworks for their excellent support!

The current Wish List

Here’s a list of all the things I “want”.
This does not include my two systems stuck overseas. Thanks Covid.

The Immediate Future

These are the things I’m actively searching for to buy as they become available. I’m not going to go silly on them. (I’m looking at you, $1,000 Microbee!)

Amstrad CPC 6128 or 464: I’d prefer the 6128, as it already has 128k, and I can easily crossgrade the internal 3″ (yes 3 not 3.5) to a Gotek.

Harlequin 128 Kit: It’s a kitform clone of the ZX Spectrum 128 / 2+. I have a Spectrum 48k, and it’s a fun little unit. Going up to the 128, I’ll probably mount it into my DKTroniks case and move the 48k back into it’s original “dead flesh” mini case. This is my “Christmas present” so I’ll probably order this sometime soon.

Microbee Kit: These haven’t been released yet, and I’m not expecting to see it before mid next year. If I see a real Microbee come up for a sane price, I’ll probably grab it as it goes past. A sane price in this context would be under $400 tested or under $300 untested.

Apple Macintosh SE/30: (New entry) So I decided I should grab a 68000 based Mac for nostalgia sake. Thinking about classic macs, the one that appealed the most would be an “All in One” Black and White unit, and what better one to want, than the SE/30? It’s a full 608030 with FPU, up to a massive 128MB of RAM, (Apparently the memory takes a full 5 minutes to complete the memory test when fully populated), SCSI and an expansion slot. I’ve really only crystallised this want over the last week or so.

Super Nintendo Entertainment System: Mostly so I can play JRPGs. Oh, and Super Mario RPG, which is possibly the most bizarre RPG idea I have ever seen. Squaresoft and Nintendo doing a comedy RPG in the Mario universe. It’s delightful!

PC Engine: The little console that could! Also known as the TurboGrafx-16 in the US. It’s just the cutest little console with some great games an peripherals.

The Upgrades and Peripherals

Stuff I want to get to improve the systems I already own.

DIVMMC Future: (Spectrum 48k) It’s a disk! It’s a Joystick adapter! It’s a floor polish! (So I might be lying about the floor polish). It makes playing games on the speccy so much less painful.

Penultimate + / Final Expansion 3: (VIC 20) More memory plus a butt load of integrated games. Would make the VIC 20 more useable.

MegaCART: (Creativision) All the cartridges ever made for the Creativision on one single cartridge, including BASIC. I’m in the process of making one of these myself, with the help of someone who designed their own.

Amiga Case: (Amiga 1200) My poor Amiga 1200 hasn’t had a case, ever. I have designed a laser cut case. I just need to join a Maker Space with a laser cutter or two and get it cut. I have not achieved this yet. I’ll want to do a test cut in MDF to make sure it all fits.

Mockingboard clone: (Apple II) A sound card for the Apple II. So that Ultima V makes music.

Z80 “CPM” card: (Apple II) A card allowing Z80 CPM software to be run on the Apple II. It opens up some extra apps and games that would otherwise be unavailable.

The Unicorns

These are those rare delicate beasts, that I don’t expect to ever own. If someone wandered up and offered one to me, or if I won Lotto, these would be the machines I’d then look at finding.

Atari Falcon: The last hurrah of Atari. A 68030 processor, up to 14MB of RAM, improved video and sound and a beefy 56001 DSP coprocessor. Almost nothing written takes advantage of these features, but it’s still an impressive piece of kit.

Acorn A5000: An Archimedes with teeth. Loads of RAM, a terrifyingly fast RISC processor, SCSI and the ability to do some quite improved VGA style graphics. The Archimedes family has always had this mythical allure. Pure unobtanium.

Commodore Amiga 4000/40: A big box Amiga, with everything that entails. A full 68040 powers this monster. Near the end of the life of Commodore, it had some interesting “step backwards” decisions in it (Such as IDE rather than SCSI) and some interesting “step forwards” decisions, like AGA. If I got one, I’d start saving for a Mediator so I could stick in PC peripherals alongside Amiga peripherals.

Sharp X68000: The “Japanese Amiga”. A 68000 based computer with a truly monstrous set of co-processors, capable of amazing sound and graphics. Expensive and ahead of it’s time. Sound familiar?

Apple Addendum

Just a quick note that a very helpful fellow on the Apple IIoz mailing list pointed out that there are two variable resistors on the top of the PAL card that can be adjusted to tweak the video output. (Honestly, I mistook them for Foil Film Capacitors as they were blue blocks on the top edge. It was only when I looked at them more closely that I noticed they had a tiny embedded screw-head)

A quick setup later and a bit of fiddling and I had perfect stable colour from the Apple IIeuroplus.

I then decided to see if I could improve the picture on the Apple IIe using the same approach (The IIe PAL basically just has the PAL card integrated) and it was just as simple! Find the two variable resistors and gently dial in the picture.

Now I have TWO Apple IIs that are fully set up with Disk Drives. Time to play some old Ultima V. Now where was that Magic Carpet again?

A light interlude of Yak Shaving

Foreshadowing – Copyright 2020

So here I am again, and yes, it’s been a while since I had any real progress with any retro projects.

I’ve been working on the Commodore C128D and it now reads disks, which is good, but it doesn’t read them reliably, which is bad. I also don’t currently trust the unit, as some C128 demos seem to crash. Unfortunately to get a test cart for it will cost some considerable $$$ that, right now, I’d rather be putting elsewhere.

Tonight, however, I finally got a second Disk II card for my Apple IIs. I’d traded this for a pair of joystick adapters (See last post). I thought this was a good deal and the kind soul I traded with also thought it was a good deal. They did warn me that there was a possible issue with the card, but they were happy to send parts to fix if needed.

So I got it home and launched into an epic evening of Yak Shaving.
For those of you not familiar with the term, it refers to that process you sometimes undergo where you start out to complete a task, but get severely derailed by the tasks you need to complete BEFORE your initial goal. The story goes something like this:
You decide to fix a component in your computer, so you go looking for a specialist tool, but when you find it, the battery is flat, so you go to find the special charger, but it only has a US plug so you start looking for an Aus to US adapter…
…and then twelve hours later, halfway through shaving a Yak, you find yourself wondering “What was I doing this for again?”

Tonight was one of THOSE nights.

It started with the Disk II card at about 6 and I hadn’t yet finished by 9:45 when I stopped.

So the first thing I had to do was find the desk. It was under there somewhere. 10 minutes of cleaning, the huge stacks of cables were gone and the C128D had gone back to the cubbyhole of shame (Where it will live for the next 6 months)

OK so now I can get to the desk. I then pulled out the card and gave it a visual inspection, and the P5 PROM was an interesting colour and texture.

Grime – Copyright 2020

YUM! Doesn’t that look delish!
I got out my sand eraser (A really excellent tool for cleaning contacts like this) and cleaned it and every other last chip on the card, making sure to seat them back the way I got them.

Once I was happy with that I had to dig out my original Disk II drives. I had stashed them deep in the tech pile as I wasn’t going to be able to use them until I got the Disk II card.

Now I had the card and the drives. Time to pull out my known good Apple IIe. Crossing fingers, I carefully plugged in the card and the drives, inserted my test software and turned it on… Some whirring and grinding and… it booted! First go! OMG!

This led to the NEXT thing. You see, the Disk II card was merely part of a long chain of steps. What I really wanted to do is get my Apple II europlus working. (There’s lots of posts about me trying to fix this system)

Now I had to lube up the disks and carefully clean the drive heads. I opened up both disks, carefully making sure that I did things like mark polarity on all cables and connectors. (Silver markers are excellent for this) then carefully clean with isopropyl alcohol and grease up the drive rails with a suitable lubricant. The drives were as ready as they ever were going to be.

Now I had recently swapped out the 16k “Language” card from one of my Clone Apple IIs for the one that was originally in the europlus and it seemed much more stable. Now I had a Disk II card I could try the system with working disk drives.

I dug out the europlus from under the clones and carefully plugged in the Disk II card and drives and turned it on… Et Volia! I was booting my test app. It all works.

EuroPlus – Copyright 2020

Except, I’m still in black and white 😦

I then spend thirty minutes looking for my PAL card (Apple II and II+s need an additional card to display PAL colour.), finding the loaner I had from a friend before finding it stuffed away in a dark corner.

One of the things I do find, however, is the Language card I’d picked up at the last Commodore User’s meet. Hmm. Let’s test that, shall we? I unplug the existing Language card, carefully disconnecting the fragile ribbon cable (Foreshadowing) and plug in the new one. The computer… sort of works. It boots up with an odd “Super ][” startup and doesn’t get much further. At this point I decide to move on. I carefully remove the card and grab the “known good” card to put back in. I’m about to connect the ribbon cable when I notice there are two bent pins.
I grab a pair of needle nose pliers and gently start straightening the pins. The first one forms properly and then “plink!” the second one snaps clean off. I swore loudly at this, as I was being careful. (It’s actually the picture in the header of the article, with the broken pin to the lower left)
Thankfully I was able to salvage the cable from the other Language card and I was back and operating in a few minutes.

I grab the PAL card and in it goes… except no colour. I can see it trying to do colour but it’s not encoding properly. The screen background (black) is blue, and white is yellow, with severe colour artifacting everywhere. As my test suite loads, the blue gets replaced by black, but there is only shades of grey, and some of the screen is still banded in blue / yellow rather than black / white.

So I grab the loaner. This only appears to have RF out, terminating, oddly, in an RCA connector.

Now I need to make an RCA to PAL Antenna cable. I go into my cable bin and find an unused RCA lead. Off to my garage parts bin to find an unused PAL Antenna end, and I think I’m ready to go. (Spoilers! I’m not)
While I’m here, I quickly grab a spare RCA end, “just in case”, and head back to my work bench. I get ready to assemble when I notice the inner core of the PAL Antenna connector is missing. This sucks because that means I can’t get away without having to break out the soldering iron. I dig through my cables and find an unused male to male PAL cable. I carefully cut it in half, and solder on the RCA end I’d (thankfully) grabbed while in the shed.

A quick bit of routing later and the cable is plugged into the antenna port on my TV and I’m ready to start tuning in the TV. Luckily my TV supports Analog RF stations. Unfortunately after 20 minutes of fiddling, I have been unable to get a stable TV signal out of the card and there I will need to finish for now.

On the one hand, the Apple II europlus is now booting to the point where I can happily work with it. On the other hand, I still need to resolve the PAL card issue, or live with Black and White. You know? It’s a secondary system. I might just live with Black and White. πŸ˜€

Inputs and Outputs

So now I have a working Apple IIe, and an ability to put software on it, my mind turned to games, and more importantly, how to control games.

You see, unlike almost everyone else, Apple had joysticks as an afterthought. (Apparently Woz wanted to play Pong). As a result, the Apple 2 supports one Analog joystick with two fire buttons, made up of the two pong controllers with their buttons. Also, to complicate things, they were made with 150kΩ potentiometers, which apparently nobody makes into joysticks any more.

I had initially thought about scratch building one, based on the work of Quinn from BlondiHacks. (Go watch her YouTube, it is both informative and entertaining). I even got as far as buying some components and designing a controller. In the end I was put off by the recalcitrant nature of my Apple II europlus.

But now, now I had a REAL computer and LodeRunner was beckoning! Taunting me!

Yes I could play it with keyboard… just. But it wasn’t fun.

What was a hacker to do?

Well, while thinking back to Quinn’s blog post above, and referring mentally to building my first Arcade Cabinet (Oh god! FIFTEEN years ago?) I remembered a trick where you could use off the shelf Arcade bits to fake an analog joystick. Arcade buttons have both a Normally Open (NO) and a Normally Closed (NC) connector on each, so you can get sneaky!

I also happened to own a LOT of Arcade bits still, as I had planned on building a tabletop machine that never eventuated. (Maybe one day I’ll get the bug again)

Off to the shops and I purchased a packet of resistors and some cable and I had a joystick! It wasn’t pretty and it was ungainly but I was playing LodeRunner like a champ! Well, I was once I got the axis in the right order. Yep. I had a 50% chance and I got it wrong. But it was playable!

And that was that for a few weeks until I attended an Amiga User’s group meetup where I purchased 2 PC joysticks and a Apple 2 memory card. It was that sort of meetup πŸ˜€

One of those joysticks was glorious. A true salute to retrocomputing.

I knew I had to get this plugged into the Apple II. Initially I tried to reverse engineer something. I knew the IBM used 100KΞ© pots, and I could use Quinn’s maths to calculate that I needed a 10nF capacitor to make it work, but I was a bit worried by the buttons.

Then I thought “I bet someone has already solved this problem!” and a bit of Googling later and I had this!

I figured I could do a nice version of this, with a case and a neat little veroboard PCB in about half a day.

About this point, a friendly soul on AppleFritter contacted me and offered me a disk controller card for my Apple II europlus. Did I want to trade anything for it? I suggested I had some PC joysticks and was about to build an adapter? He said he was interested in two as a swap so away I went. Oh, and that I should join the Apple II mailing list for Australia.

The second topic posted? “Anyone have an Apple II joysitick?”

How could I resist?

A quick discussion ensured and I agreed to sell him an adapter with an IBM joystick for a reasonable price. He was happy. I was happy. All I had to do was make them…

It took all weekend but I got there. In the end I mucked up exactly one thing. Stupidly, I forgot (As I do every time) that IEC adapters change the wires order to 1-6-2-7-3-8-4-9-5. D’oh!

A quick resolder of my original model and away it goes!

So for each of them I made a small circuit for the 2 resistors and 2 capacitors. I had to narrow the metal of the DB15 (And then file it off so there were no rough edges). Each board had to be soldered to the two connectors, and due to clearance issues, I had to ever so slightly widen the case at the DB15 end.

Why is the 9 pin on a short cable? Because that way it won’t be acting as a very effective fulcrum on the Joystick port on the back of the Apple II.

WHAT WOULD I DO DIFFERENT IF I HAD TO DO IT ALL AGAIN?

Well, lets say I had to do a whole bunch of these, there are certainly a bunch of changes I’d make.

  1. I’d make a PCB.
    1. That PCB would have the DB15 mounted on the edge of the board, to save space. Also a LOT easier to solder than individual wires.
    2. The other end would have a 10 way pin header so I can make up a cable with IEC connectors on each end. It’s SO fast to make.
    3. I’d add an inline potentiometer on the X and Y axis so you can really tune them in.
  2. I’d set up a rig so I can repeatably mill out the ends of the cases.
  3. I’d find a suitable tool to allow me to nibble rather than file the ends of the DB15 connectors in a neater way. I’m sure there’s something out there.

So it was a weekend’s work but I learned a lot and was VERY happy with the result. Oh and LodeRunner is a lot easier with my lovely retro-joystick.

Apples and Unicorns: A sudden rush of RetroComputing (Repost)

(Originally posted on LinkedIn Jun. 24, 2020)

Retrocomputing is a funny hobby. When you’re dealing with computers that are 20+ years old, most things tend to plod along at a stately pace. Maybe a new upgrade here. Maybe a new purchase there…

And then there are periods like that since my last post, where over the period of a fortnight I gained several new systems in a rush.

A Bunch of Apples

First up, as I have posted before, my Apple IIeuroplus is not a happy piece of fruit. I’d described changing the RAM, but I was despairing. I’d planned to use the Cassette port and use the rather nifty site here to download some diags disks, but it wasn’t even reliable enough to do that. I’d decided there was nothing more to do, so I packed it all away and got on with my life.

Then, almost out of the blue, the person who gave me my initial Apple II mentioned they knew of someone potentially interested in divesting themselves of an Apple IIe, the enhanced model of the Apple II. Was I interested? Ooh yes please!

I reached out to the individual with the Apple IIe, and offered to either pay or swap for a Commodore 64. They got back to me quite quickly and said that as they had got the Apple IIe for free, they didn’t want anything for it. It had been sitting idle for ten years and they wanted the space back. Oh, and did I want a couple of untested Apple II clones as well?

I was gobsmacked by this super nice offer! I took them up on it and arranged to collect the systems.

And then a Unicorn appeared…

In the context of collecting, a Unicorn is any super rare item. So rare that they may as well not exist. An item that, if you want one, you better be prepared to pay.

In my eBay “Saved Searches”, a super rare computer I really wanted appeared, and it was at a reasonable starting bid! This was the fabled “Dick Smith Wizzard” AKA the Creativision. I’d only seen two come up in 3 years of watching, and one of those was a $1500 “complete collection, in box” that I just couldn’t justify. I carefully put in a bid, with a maximum bid of $251.50, the odd amount being slightly over a $50 mark, as many people stop bidding at multiples of $50. I was the front runner at $199!

And that’s where it sat for the first four days of the 7 day auction. I was hopeful that maybe this time I’d get the prize, but I didn’t want to get my hopes up as surely I wasn’t the only hunter after this particular prize. Sure enough, with 3 days to go a rush of bids appeared and the price shot up to $210, then $250, where it sat for a few hours, and then a flurry up to well over $350. This was more than I could easily justify for a system with only a handful of games, even if I did have an emotional attachment to the system. Dejectedly I shut down eBay and mentally “walked away”. Some lucky hunter would get the prize and be happy. I consoled myself with the thought that in the next day I’d be getting some Apple IIs.

Collecting the Apples

At the arranged time I drove out to meet the collector. We chatted for a good half hour about all sorts of things in the domain of collecting old systems. They were primarily a Mac collector, and had got the Apples as an “Adjacent” system, rather than as part of their primary collection, thus their preparedness to give them up to gain space. It turns out that I knew the original owner of the systems, in a very “Perth” kind of way.

The haul included a CRT Greenscreen monitor, a DuoDisk twin 5ΒΌ” Drive and the three systems. I thanked them again, loaded up my car, promised to keep them in the loop on the status as I looked at the systems and headed home, as I had a meeting coming up.

I got home, unloaded the car and joined my wife on the couch to attend the meeting. (It was a video-conference)

About three-quarters of the way through the meeting I was idly checking my phone when I got a message from eBay. The subject line was “eBay Bid Change Notice”…

The Hunt Rejoined

I blinked, and carefully read the e-mail. “…The following item, on which you placed a bid has had a bid retraction or cancellation, and you are now the high bidder.”

Wait, what? I was the highest bidder again? Whoa! I nearly cried. I showed my wife who was suitably amused. Later that evening I got outbid again, but only by a slim margin.

Meanwhile I had cleaned up the first of the Apples (the IIe), inspected the power supply for correct voltages, and got it to boot to a prompt. An excellent start. I carefully added in a Floppy Disk card and Drive. It was now booting from floppy disks. I ran the onboard diagnostics and it passed all tests. Exciting! These tests also revealed that the IIe had a memory / 80 column card upgrade in place already. Nice!

I also inspected the two “Clone” Apples. (One of them had a handwritten note identifying it as an “Orange”, and sure enough, where there would normally be an Apple Key, there was a round Orange Key instead). One turned out to be a clone of the Apple IIe and the other a clone of the older AppleII+. Unfortunately there were no ROMs in the sockets of the II+ clone.

Moving back to the genuine IIe, my next step was to see if the serial card that had given me such problems on the II+ would work at all. If it DID work I would be able to use a serial link to read disks off my PC. In it went, no errors, no problems. This was looking really good! Next step was to get the transfer software over onto the Apple. This was one of those classic “Chicken and Egg” problems where if I had the disk, I could make more disks, but I’d need the disk to make the disk… or did I? Remember that useful site at the top of the article? I had seen people mention that they’d found it the most reliable way to get the needed first disk. What did I have to lose.

I grabbed my trusty iPad, found an audio lead and plugged it into the Cassette port at the back of the Apple II. I stuck a blank disk into the disk drive. I booted the Apple into it’s BASIC command line from the onboard ROMs and told it to “load” from tape. On the iPad I then played back the carefully constructed WAV file at full volume. It picked it up and proceeded to load a preloader! This preloader then formatted the floppy disk and copied over the rest of the disk image to the floppy. Was it that easy?

Why yes it was, and also fast. As someone used to the infamous C64 serial based floppy disk drives, the Apple II Disk is lightning fast. I booted off the freshly minted disk and it worked! Now what? My next obstacle involved me fossicking through my box-o-cables until I found a long USB cable. (Thanks past me for saving that 5M USB2 AtoB cable). I then dug out my USB Serial port and plugged it in. There was a bit of excitement when the server part of the software decided it didn’t like the serial port, but a reboot fixed that in short order. The next order of business was a simple one, but threatened to derail the project. I needed a 9 pin to 25 pin serial adapter. After a thorough look through my collection, I asked my housemate if he had one. He did! It was still plugged into a modem. πŸ™‚

I had communications! The two systems were talking despite the 25 year difference in age between them. However, my initial attempts to transfer data all failed. There was one final obstacle would not be solved to the next day.

Meanwhile…

I had now been outbid on the precious “unicorn” system. I knew I could afford a bit more but didn’t want to push it too hard. The auction was due to finish the next day at 1:30pm. I decided to sleep on it and see if I still wanted the system in the morning. My wife was supportive (She puts up with SO MUCH) and when I got to work in the morning I had decided to up my bid to $327.50 and to leave it there. I’d either get the system or I wouldn’t. I put my bid in and the price jumped up to $311. I was still in the game. I spent a nervous day, occasionally checking eBay but otherwise trying not to get too excited. With an hour to go I decided to “cold turkey” out of eBay and just see what happened. All the excitement was infectious and I found myself working on my real work much more intensely than usual. And then… “You Won!” came through my e-mail. I had got it for $311. That evening I arranged to pay for the system, and the seller contacted me to say he’d ship it Wednesday morning. I haven’t yet received it, but I’ve already started researching what else I can do to improve the system.

Back to the Apples

Now I had the “unicorn” under control and corralled, I could get back to my Apple computers. That night I started playing around with my newly created Serial Link setup. Initially I thought it was related to the sources of media that I’d found, but then I realised it was my media. It turns out that a good percentage of 30+ year old disks are going to be unreadable. Finding some unused disks in my collection, I tried again and I had successfully imaged across a game that I wanted to try on the Apple.

Great! My game boots! I can play! Only one problem. It was all black and white. So I tried it with a different monitor (A Commodore 1901 CRT, designed for my Commodore C128D) and it was still black and white. I then tried it with an Apple Colour monitor. Colour! But why is the blue showing as pink and the red showing as green? It’s not like I’m splitting out the colour as RGB… That monitor started failing about that point so I put it aside for another day. (I hate working on CRTs. I have been working on them since the early 90s and I still hate them. So many ways they can fail in spectacular and antisocial ways. Even with the “right” tools like a proper discharge strap I just don’t wanna!). I also tried a Composite to HDMI adapter and only got black and white. Anyway it was time for bed so I put it aside for another day.

The next evening I had another window of time, so I decided I wanted to the bottom of my colour issue. Jumping on my usual Apple II forum, I did some searching to see if anyone else had hit a similar issue. Almost immediately I found a post of someone with a similar problem. Scrolling through pages of in-depth technical discussions on the differences between PAL and NTSC systems, timings, Capacitor values and other minutiae, I finally reached the bottom of the article. The original poster hadn’t solved their problem, but a year or so later a different poster had added “I fixed my colour problem by switching the switch on the motherboard from “mono” to “color”. Wait, what?

Sure enough, opening up the case and looking at the board revealed a tiny switch on the right hand side of the board labelled “mono/color” and it was in the “mono” position. Several minutes of swearing followed. A flick of the switch and I had colour in my games.

This was about the point (in between forum searches) where I also checked out the voltages on the clone IIe (Henceforth referred to as the Orange) to see if I could get anything out of it. Voltages checked out fine. I plugged it all in, turned it on. It beeped but no picture displayed. I re-seated all the obvious chips and tried again. Still got a beep then nothing. Oh well. It had been given to me as “not working” so that was fine. I figured I’d look at it later. Shortly afterwards I plugged the Apple IIe in to the same setup and also didn’t get a picture. Waitaminit. Sure enough the OTHER end of the video cable had come unplugged with all my video testing. Plugging it back in and testing again, my Orange IIe booted to the command prompt. Huzzah!

The Future

At this point I’m quite happy with the Apple IIe and Orange IIe that I have. I don’t have enough parts to add a Floppy drive to the Orange IIe yet, but once I’ve tested the cards from the Apple in the Orange, replacement cards are actually not too hard to come by. I also need to see if the ROMs from my Apple IIeuroplus work in the Clone II+. Maybe between the two I’ll be able to get a II+ working. There’s also a project afoot to make a replacement ROM set for the II / II+ family that would help get the system back on it’s feet.

Long term, the Apple II is very expandable. Upgrades I’d like to get in the coming years include a soundcard, a virtual Floppy Disk and a Z80 card so I can run CP/M. With the prices though, it’ll be a slow process.

As for my new “unicorn”, I think I’ll investigate a Composite mod for it, as well as some other “homebrew” kit. Options include a tape interface and some sort of “universal” cartridge.

Reocomputing: Two Steps Forward, One Step Back (Repost)

(Originally posted on LinkedIn Jun. 15, 2020)

Retrocomputing continues to help me find my happy places.

I’ve been extensively working on new things. I recently rebuilt the area all my consoles live, to simplify things, going from having to use four different remotes in various combinations, down to two, one of which is only used to turn on the telly.

Currently I have seven different devices plugged in, all using different connection technologies, all needing to be scaled. It’s a nightmare of cables and adaptors but I got there in the end and now it all just works.

I also finally “emptied” a project box by finally fixing one of my retro computers. I now have a working C128D. It had stopped working a while ago, with the PSU tripping under load. After a lot of research, trawling through forums and finally asking someone to break out a multimeter and measure some resistances, I was confident the issue was with the PSU. A complete rebuild later and it’s happily booting! There’s a couple of minor issues I want to resolve with the disk drive, and I want to heatsink the custom chips but I’m generally very happy with it. Can’t wait to fire up some of the more obscure titles that could take advantage of the extra processing power over the C64.

As for the Apple II, it still isn’t working any better. I need to get it back on the bench. I’ve had someone suggest a rather clever website that plays back audio files that I can then play directly into the Apple II tape port, which will then (hopefully) write out a disk for me.

The Apple II forums I hang out in suggest I should probably just abandon my current model, due to all the limitations it has, and get a newer model. Unfortunately that’s not cheap, particularly as they’re not well represented in Australia, so I’d most likely need to import one from the US, easily doubling my costs through import duties and shipping.

I’ll keep that as a backup option. Until then I’ll keep slogging on with this one. The price (free) was certainly not something I could argue with.

I’ve started thinking more about my “next” purchase too. I’ve managed to secure an Atari 800XL, a lovely 8 bit machine designed by engineers who went on to design the Amiga. Unfortunately it and the BBC Master system are stuck in the UK by Covid 19, as the people who were going to bring them back to me have been under isolation for several months now. I think I might just have to “bite the bullet” and get them to ship them to me.

I’m thinking about getting an Amstrad CPC system, most likely the CPC6128, as it’s a nice sweet spot of compatibility and power.

After that it gets more difficult to choose. I do have a wish list, but some of the remaining systems are tricky to source at the best of times. I’d love to add an Acorn Archimedes of some sort. A Microbee would be a lovely Australian system to have, but I suspect the next thing I’ll actually get is a Harlequin 128.

I still need to get my NES working, so I will need to order a proper edge connector for mine, as I’m 99% sure that’s the issue. I have located an improved edge connector, but once shipping is factored in, I’m going to have to save for this one. I’ll get there, just not this month.

Continuing Adventures in RetroComputing (Repost)

(Originally posted on LinkedIn May 18th, 2020)

Based on a picture from WikiMedia: https://commons.wikimedia.org/wiki/File:Apple_II_Plus_Inside_Microsoft_80_Column_Card_Closeup.JPG

As I have posted here before, my current hobby is fixing up old computers. Some of this involves working with components and tools not easily available at your local walk-in electronics store. Some of these can be covered by the “usual suspects” such as RS Components and Element 14, (My preferred suppliers) but some of these can only be purchased from obscure suppliers, often in China.

As you can imagine, recent global events have slowed the supply chain down dramatically, but things are finally starting to trickle through.

As a result, I was finally able to tackle my Apple II+ recently, having finally received my 4116 DRAM chips. The Apple II used 3 banks of 8 of these to generate the first 48KB of memory, with an additional bank of 8 on a “Language Card” (So called because they were needed to run additional languages such as PASCAL) to bring it up to a compliment of 64KB.

The whole point of this was to get the whole shebang ready to run a serial link back to a PC so I can copy across floppy disk images.

Unfortunately I still have an intermittent issue with memory corruption, and it’s really annoying. I am in a “chicken and egg” situation insomuch that, if I had a working system, I could get diagnostic disks made which would help me to resolve the issue, but as my system doesn’t work, I can’t get the disks, which means I can’t find the problem…

(Insert joke about holes in bitbuckets)

I’m not giving up, however. My current plan is to pull it all out of the case and check key busses with an oscilloscope. See if I can isolate out where things are “going bad. I’m also tempted to get a EPROM programmer, as many of them will also test 74 series logic. I may also see if someone on the various Apple forums are willing to burn me a couple of Diagnostics disks.

If that fails, I might just have to buy another Apple II to use to help me fix this one!

Here’s a list of what’s already been found and fixed:

  1. Many chips with significant oxidation on the legs. They looked like they had been steeped in strong tea with a browny black patina. Cleaned with a sand eraser and their sockets cleaned with electronic contact cleaner. This improved things a lot, and got me to the point where it’s semi-stable.
  2. Custom cable constructed to connect from the Floppy controller to the Floppy drive. I had to customise both the cable and a connector. Apple used a 19(!) pin D connector, which I worked around by getting a 25 pin connector and pulling 6 pins out with pliers.
  3. On the Language card, replaced ALL the 74 series logic chips with new ones. Also replaced the ribbon connector between the card and the motherboard. This was, once again, a custom made part.
  4. Identified and replaced all 4116 memory chips. I believe all the ones I was using are good components as I “swap tested” them, but it was cheap to swap out all of them, so now they’re identical. I did find several bad ones.

Retrocomputing News (Repost)

(Originally posted on LinkedIn Feb. 6th, 2020)

(Image from Wikimedia, used under a CC license - https://commons.wikimedia.org/wiki/File:Acorn_BBC_Master_Series.jpg)
(Image from Wikimedia, used under a CC license – https://commons.wikimedia.org/wiki/File:Acorn_BBC_Master_Series.jpg)

Well, I continue to collect old computers and consoles. It’s a fun hobby and exercises skills I don’t get to use at work as much any more.

The pleasure of starting with a beat up old system and getting it working properly is a real buzz, and lets me practice both practical skills (Such as soldering) and analytical skills (Such as fault finding).

Currently the collection is getting along nicely.

I have the following computers:

  1. A Commodore Vic 20 (5k RAM, 1MHz 6502)
  2. A Sinclair Spectrum (48k RAM, 4MHz Z80)
  3. An Apple II europlus (48k upgraded to 64k, 1MHz 6502) – I have replacement RAM on order for this beastie. Until then it tends to “barf” whenever I try to load a disk needing more than 32k.
  4. 4 x Commodore 64 (64k RAM, 1MHz 6502) + an assortment of peripherals, such as disk drives, printers and such
  5. A Commodore 128D (128k RAM, 2MHz 8502, 4MHz Z80, Integrated FDD) – Sadly this machine needs more work as the power supply trips when I turn it on
  6. A BBC Master System (128k RAM, 2MHz 65SC12) – This is so new, it’s still on it’s way to me
  7. An Atari 1040 STfm (1M RAM, 7MHz 68000) – Upgraded with a Gotek Floppy disk emulator, a nifty gadget that allows you to use a USB stick to pretend to be a floppy drive.
  8. A Commodore Amiga 1200 (2M RAM, 14MHz 68EC020, AGA Graphics) – This one is waiting for me to get a chance to laser cut the case. I have extensively customised this one, as it had been “hacked” before I got it. This taught me a lot about circuit board design as I designed and ordered my first commercially manufactured PCBs for this system. This also has a Gotek.

I am also building up some “classic” consoles too:

  1. 2 x Nintendo Entertainment Systems – Neither work currently but I know why. I just need to actually buy the part to fix it.
  2. A Sega Megadrive – I’ve been trying to get decent RGB Video out on this for MONTHS, but it’s manage to elude me so far. I’m not giving up yet though. A new week, a new version of an RGB cable.
  3. A Commodore Amiga CD32 – Oddly this one can be very easily upgraded to be a full blown computer comparable to the Amiga 1200 above. So far I’ve resisted the urge.
  4. A Sony Playstation 2 “Phat” with an added hard disk and network card.
  5. An original XBox. (Dear Microsoft, calling your THIRD XBox console the “XBox One” was a dick move. Seriously. Do you know how hard it makes getting info about the original?)
  6. 2 x Nintendo 64. Mmm. Tetrisphere was such a masterpiece.
  7. A Nintendo Wii. The optical drive has died so I use an external HDD instead. Much more convenient.
  8. An XBox 360. Eh. It was cheap.
  9. A Playstation 3. I bought this new. It was shiney when I got it. A particularly nasty weekend doing far too much overtime payed for it.
  10. A Wii U. Kids got it as a Christmas present, when they were no longer very new. I like Breath of the Wild on it.

I also have a Raspberry Pi setup as an emulator to cover those systems I haven’t yet collected. If you are only casually interested in the old systems, these come highly recommended!

Once I have the Beeb, there’s not too many “must have” systems on my wish list, not counting the occasional “Unicorn” system out there that I’m unlikely to ever get.

I still want to get an 8 Bit Atari, such as the Atari 800XL, and I am actively searching for a Microbee, either in kit form or an original. (These were used in Australian schools in the 80s). I’m also likely to buy a Harlequin 128k kit (Emulating the later Spectrum 2+). Finally once I have all those I’ll probably start looking for an Amstrad CPC 128.

As for consoles, I’d like to add a Sega Dreamcast and a Super NES. However I keep my eyes open for the disturbingly rare Dick Smith Wizzard. (AKA the CreatiVision) The latter is definitely veering towards “Unicorn” status.