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PC-98 – Window Accelerators

Thanks to the complexity of Kanji characters, early Japanese 'DOS' machines needed high-resolution text displays. This requirement resulted in the PC-98's 640x400 standard console mode. The video cards to run this were purposely-built and were never really meant to run Windows.

Due to these limitations, companies started coming out with "Window Accelerators" which provided a secondary video device, of which could produce much higher resolutions at higher colour depths. I happened to get my hands on an IO-DATA GA-1280A-2, capable of 1280x1024 @ 256 colours.

Being a secondary video device, these cards require a passthrough cable from the primary machine video output to their 'input' port. When the machine is displaying standard PC-98 graphics, accelerators will route this output straight to the monitor. Once the card is initialised, you'll hear the internal relays 'click' and video will be displayed from the card's internal ram buffer, which specific software is now sending the graphical data to.

Unfortuantely, my specimen came as-is with no cable... so a trip was made to Jaycar for a male and female set of ribbon-crimp IDC 15-pin plugs.

The card was mounted in the machine and the wiring was hooked up...

With no drivers, the card will just pass the standard video through. This is what happened until I installed the drivers for DOS and Windows 3.1. And then? Reboot... a beautiful "CLICK" from the relay on the card and...

Windows 3.1 at a ridiculous resolution.

Does it play Doom?

By default, a PC-9801 can't play doom with it's in-built EGC video card. The settings only give you the following options:

And yeah, GA-1280* is there and it works perfectly.. not even needing other drivers! Well. It runs terribly on the PC-9801VX, even with the 486 Upgrade. The shots above were taken with the card installed in my newly-acquired FC-9801K with 486-Overdrive processor and Doom runs nicely!

PlayStation 2 – Linux And VGA

Back in University, our fourth year project was a Billiards game on the PlayStation 2. I still don't know how we wrangled making games as an educational experience, but it was fun nonetheless. We used PS2 Dev Kits that came with a linux distro, mouse and keyboard. There was also a VGA adapter which only worked with sync-on-green monitors and I specifically remember having to make a lot of desk space for the 21" Sony Trinitron. Since I'd been mucking around with the 'fake' HDD adapters for the old PS2s recently, it came to me that I should try install Linux and get VGA-out going... turns out it's not as easy as one might think!

Third-Party HDD Adapters Won't Work

If you've got a SATA adapter by PPH, or something similar, and the ethernet port is covered, or totally missing, then you're out of luck. The Linux distributions I've tried require the Original Sony HDD Adapters (or one of the original clones that HAD ethernet) and will just freeze up and stuggle if you try anything else.

Fortunately, I'd secured one for AU5$ from a Hard-Off somewhere in the bowels of Japan. Currently they're going for AU50$ on eBay AU, or ~AU20$ on Yahoo Auctions Japan.

Free MCBoot As A Bootloader

You'll need Free MCBoot installed on a memory card, unless your PS2 is already physically modded. Some versions of the PS2 work with a simple "DVD" method to install Free MCBoot and you can follow these instructions if your that happens to be the case.

I disregarded the warnings and tried to use the ISO that lined up with my 5000x version, as per the version info:

It threw the expected error...

The alternative method is to make the HDD bootable to, in turn, make the Memory Card bootable. It's all a little chicken-and-egg, but it worked in the end. I downloaded the FHDB installer 1.966 and used the HDD Raw Copy Tool to flash the IMG from the archive over the HDD I indended to use in the PS2.

This disk was connected to my PC via a USB adapter to do so. Note that I was using a blank HDD here... don't use a drive with precious data! Slap the freshly formatted HDD in your PS2 and boot it up. At the same time, copy the guts of this zip file to a folder on a USB key, as we want to run the installer to get the software installed onto a Memory Card. On the PS2, scroll down to uLE/wLE and navigate to MASS and then the folder you used above. Select the installer and hit the circle button.

After it's done, shut the unit down and unplug the HDD. Reboot with just the memory card in to make sure that it works. From here plug the HDD back into your PC and format it with WinHIIP so that it wont try to boot from the HDD again!

Linux Live DVD

You'll find a miriad of Linux Live DVDs here. We'll go with Version 3. You'll then find a huge list of ISOs to choose from. We'll take the PAL Large No Modchip. Download and burn it to a DVD. Whilst that's happening, grab Kernel Loader 3.0 and copy it to a USB drive. We'll need to copy this to the Memory Card...

Disregard the jump to the kloader folder. In fact, disregard that that folder even exists. Just use the R1 shoulder button and paste the kloader file in the root of MC0. Once it's done... insert the DVD and run the loader!

I was joking... don't insert it yet. As you can see above, they've added a DVD video folder with a static image to tell you that the DVD ain't bootable... thanks for the warning! So, boot into Free MC Boot, scroll down to the Loader, open it and, whilst it's opening, put the DVD back in. You can then select the kernel loader from the memory card and go for gold.

We're up, and we can ping! The experience is as slow as molasses from the DVD and sound doesn't work... but let's get installed first.

Installing to the HDD

There's a great tutorial here that I followed to get this done. Download INITRD.GZ, VMLINUX.GZ, ps2fdisk and fstab and send them to a USB Key. Boot into the Linux Live DVD and open xterm.

As above, insert the USB key into the PS2 and mount SDA1 in Linux. Copy ps2fdisk from the SDA1 to a usable folder and partition the disk. Note that you cannot use the already-included ps2fdisk from the Live DVD.. it just wrecks your HDD setup. Meanwhile, since we're using a memory card to bootstrap the HDD, we can wipe the entire HDD and use the lot for our Linux partitions. Just make sure to not try and fill the entire disk with the second partition as you'll get out-of-space errors. Next, mount it and copy everything over. Finally, copy FSTAB from the USB key to the hdd's /etc/ folder. Once all that's done... reboot. It's now time to configure kloader!

Finally, reboot and copy INITRD and VMLINUX to your Memory card.

As above, reset the configuration and then set the Ramdisk, kernel and root partition. Save the configuration the Memory card and boot. Excuse the shitty video quality as my internal HDMI capture card stopped working and I had to switch to a crappy USB HDMI capture device. Also notice how much quicker that boot was when compared to the DVD boot above. And yeah, still no sound. Let's fix that...

Getting Sound Going...

Seems the 'drivers' are IRX files and we can borrow them from game discs. Unfortuantely, the newest versions don't work, so use these files: LIBSD.IRX and SDRDRV.IRX. Copy them to your USB Thumb drive and insert it.

Follow the above steps to copy them to a folder called kloader on MC0.

Next open up kloader and configure the modules. Choose the configuration rows with upper-case file-names, just because. Sound! Network! We're up! But the video quality is awful...

VGA Output

So, officially, the PS2 outputs R+Sync-On-G+B. This means that your monitor needs to understand that the green channel is a combination of video synchronisation and green data. If it doesn't then you won't get a picture. Fortunately, and since this whole topic is already 20 years old, there's numerous people online who have already solved the problem for us: use an LM1881N sync-splitter.

                      LM1881(M or N)
                         ========       
 VGA PIN 13   -----------|1    8|-----  +5v PS2 PIN 10
                         |      |
 VGA PIN  2  --\   0.1uF |      |
 PS2 PIN 12  --+----||---|2    7|    
                         |      |          ____ 680 kOhm Resistor 
                         |      |    /----|____|----\
 VGA PIN 14  ------------|3    6|----|              |-----\
                         |      |    \------||------/     |
 PS2 PIN  8 --+----------|4    5|          0.1uF          |
 VGA PIN  6 --|          ========                         |
 VGA PIN  7 --|                                           |
 VGA PIN  8 --+-------------------------------------------/ (GROUND)

PS2 PIN 11 ------------- VGA PIN 1 (RED)
PS2 PIN  9 ------------- VGA PIN 3 (BLUE)

PS2 PIN  4  -- AUDIO RIGHT                                      PS2 PIN  7  -- SVIDEO CHROMA
PS2 PIN  3  -- AUDIO RIGHT GROUND                               PS2 PIN  5  -- SVIDEO LUMA
PS2 PIN  2  -- AUDIO  LEFT                                      PS2 PIN  8  -- SVIDEO GROUND
PS2 PIN  1  -- AUDIO  LEFT GROUND                       (Share PIN 8 with GROUND in above circuit)

PS2 PIN  6  -- COMPOSITE VIDEO OUTPUT

So, it's all pretty self-explanatory above. The PS2 AV port provides +5v, so I've used that... regardless of everyone saying to use an external source? I've also used a 680kohm resistor as the original 585k was nowhere to be found. Finally, tie all the video grounds together, leaving the audio grounds separate. Also note that PS2 Pin 1 is left-most as you're looking at the PS2.

I built up a crappy prototype and tested it out... haphazardly...

And it worked beautifully! So I mounted it a little more safely in a crappy ziffy box from Jaycar...

And gave it a spin on a real monitor...

And yes, your success may vary. You'll need to configure two variables in the boot loader and if you only configure X and not the console, you'll get the distortion as above.

Oh yeah, to configure VGA output, just press R2 when you're at the kernel boot loader and it'll cycle through the video modes. Then you just need to edit your kernel parameters to include the following: crtmode=vesa0,60 xmode=VESA,1024x768x24. Note that you may have to manually create an xmode config file in /etc/ with the contents VESA,1024x768x24 if X doesn't listen to the command line argument.

Success! I've started productionising the adapter, so tell me if anyone wants one!

Still waiting for a few parts.

What's next?

Of course, after doing all this, I find there's a newer version of Gentoo for the PS2? Learn how to build a bootable USB here. Unfortunately, the newer version doesn't support sound?.

I wonder if I can build OTTD, like I did on the PowerCenter 180.

Sony HitBit HB-F1 II – Power Supply Modifications

Whilst picking this up from a Hard-Off in DenDen Town, Osaka, I was told by the cashier that there was no power supply and that finding one would be a challenge. I wasn't too worried about this as using a 110v power supply in AU is just painful. Secondly, there seemed to be enough information on the internet to rig something together once I'd found time to do so back home.

So yeah, the power supply is a three-pin jack with AC 18v, DC 9v and Ground. This is confirmed on my unit by the voltage ratings inscribed on the base of the unit.

Finding an external supply with these two voltages would be an expensive task, so the better answer was to review the two links above to see what they did to convert. After a quick scan, it seemed that the AC voltage was used to create a -12v rail for the cartridge port and a +12v, which also was only for the cartridge port?. It seems that the MSX itself only needed the 9v DC, which it then also converted to 5v DC to run the entire system. Let's open'er'up! There are six screws under in the base that need removing. The lid will then lift off. The keyboard can then be removed, being gentle with the mylar ribbon cable.

You're then presented with the RF shielding. They've used a plastic-coated foil and it's quite soft! It's held down by screws around the bottom half, so find them all and remove them.

From here, it's the usual Sony-esque work of art. The PCB is so clean and tidy and the layout is precise. All the power paraphenalia is top-left and most of it will be redundant once we're finished with it. We're removing the power socket, so I went ahead and removed the motherboard from the case. There's 3 screws holding this down.

They went out of their way with the PCB graphic layer. They've actually drawn the connecting circuit lines on the underside of the board. There's no need to constantly flip it over if you're trying to trace a connection! There's also amazing information on pins of important ICs... and, for that note... DC sockets?

Seeing this written on the underside of the power plug threw me! Can I just supply the above voltages and get away with it? I won't need a complex supply for AC voltage if this is the case? I wired in the 12v line and, well, nothing came out! Hah. This seems to be a mis-print on the PCB? Those are NOT the voltages required.

So, I could go on about how I tested voltages in random locations and got some things going, whilst others stopped... and vice versa... but I wont, I'll just present the answer for this unit. You'll need a power supply that has +5v, +12v and -12v. Officially, you don't need the latter two if you're just using boring game cartridges. The unit only makes +12v and -12v to send to the cartridge port, and these are only used for "special" carts.. such as RS-232, etc.

Because I'm a perfectionist, I wanted to not 'downgrade' this machine... so I chose a Pico-ATX supply, as it had all the required supply voltages and an easy-to-use DC socket.

I de-soldered the ATX plug as it was just going to consume vital space inside the MSX.

On the MSX board, there's a large horizontal cable marked +/-12v. Desolder this from the left end and solder the appropriate wires to the associated supply voltages on the PicoATX.

Finally, there are two 7805 regulators that need to be removed. There's one that's bolted to the heatsink on the left and I de-soldered the wires from the mainboard. There's another nearby with a tiny heatsink on it that also needs to be removed.

With them both out, just flip the board and solder a wire into each of the OUT pins.

These need to be fed with 5v. I love how, even though the top regulator doesn't have the OUT pin described, that you can follow the traces easily from the IN of the lower regulator. The jumper wire, on the other side of the board, in the top-left of the image is drawn on this side of the board!

Once you've de-soldered the power socket, print out my personally-designed DC socket mount and use it to mount the DC socket to the board.

Finally, de-solder the power switch cable from both ends. Using one side of the power switch (it's DPST), connect one pin to ground and the other to PS_ON on the PicoATX.

Jam the lot back into the case.

When re-assembling, make sure to not screw the latches on the printer port. Try not to slice your fingers as you pinch them together and feed the board into the case.

Don't forget the two screws on the back of the case which hold the RCA socket and DC socket in place. These poor connectors get a lot of punishment. Before totally closing up this machine, I threw all the parts I removed into a zip-lock bag and stuck it under the lid. You never know, someone in the future might want to restore it to original condition?

And then it was done! Test? Of course...

Unfortunately, this unit doesn't have cursor keys! It's only got the gamepad directional arrows, and so I can't even play my favourite game.

Atari 7800 Controller Button Replacement

This Atari 7800 Gamepad came to me with one of the plastic buttons missing. They're held into the shell via two 2x2mm lugs and they must have perished after decades of abuse.

Without waiting around, I popped open the case and measured up the surviving button.

The button has a slight gradient on top, which I'm sure my 3D printer will struggle with...

And underneath there's a small tab to press on the rubber membrane inside the controller. Anyway, straight into Tinkercad I went to design a replacement.

I didn't even bother with the tab on the base... it's all just flat. The rubber membrane in the controller has a flat top anyway.

It printed OK! Could do with a sand, but I didn't have any wet-dry.

Not the prettiest... but it works perfectly! Here's the STL.

def concat_episodes(episode_name, concat_files):
    plfile = "file_list.txt"
    f = open(plfile, "w", encoding="utf-8")
    for filename in concat_files:
        f.write("file '" + filename + "'\r\n")
    concat_command = f"ffmpeg -stats -safe 0 -f concat -i {plfile} -c copy '{episode_name}'"
    print(concat_command)
    subprocess.run(concat_command, shell=True)

def concat_episodes(episode_name, concat_files):
    plfile = "file_list.txt"
    f = open(plfile, "w", encoding="utf-8")
    for filename in concat_files:
        f.write("file '" + filename + "'\r\n")
    f.close()
    concat_command = f"ffmpeg -stats -safe 0 -f concat -i {plfile} -c copy '{episode_name}'"
    print(concat_command)
    subprocess.run(concat_command, shell=True)

Random HDMI Capture Cards

I can't believe I'm calling these cards retro, but they are! They're all early 00s and the drivers are only for Windows XP and Vista? How random... I had no idea there were cheap PCI-E HDMI Capture cards back then. I would not have had any reason for them back then, and hardly do today, but I'd picked them up in a Hard Off somewhere across Japan for 1$ each and thought I should finally test them out.

DRECAP DC-HC1

First up is a DRECAP DC-HC1. It's tiny and came with a low-profile case bracket. I unscrewed the bracket and loosely placed it in my machine, making sure to NOT move the HDMI cable once connected.

Whilst looking for drivers... actually, prior to that, whilst trying to ID the card (there are no valid serial numbers or other identifying marks), I found other cards that also seemed to be identical. I then stumbled across this blog post which indicated that the base card was a Timeleak HD72A and that the drivers could be found here.

With the correct drivers installed, everything worked nicely!

KEIAN DM626 H3

The second card was identified via Yodobashi Camera product listing! How cool. Out of stock! Knowing the product name, I then went googling for drivers. It turns out the original site is long gone and, since their support page had ugly javascript, webarchive can't help to find drivers.

I stumbled across this blog post with great info on installation. It turns out you can use the Monster X3A drivers here for this card. The X3A only has one port, so it seems we'll only use the closest port to the motherboard? ... it actually turned out that any port on the card worked! Unfortunately, sound didn't.

Mucking around with Composite Signals

As that I couldn't get audio from the second card, I went with using the bracket of it on the first card! I wasn't ready to have a loose card hanging around inside my PC's case.

The HDMI port, by total fluke, lined up 98% and cables were securely connected. From there, I purchased this little beast for AU12$ on eBay...

And you know what? It works nicely! Here's a Sega Master System II hooked up. I've got a switch to toggle the PAL/NTSC pin, so when you see (and hear) it switch from PAL 60 to PAL you'll know why!

Nice... No more mucking around with other TVs... I can now use this to continue the long chain of Atari and Sega mods/repairs.

Christmas ’94, Tandy-Style!

This turned up on eBay and I couldn't resist! Recently I'd found stamp books and Australia Philotelic Assoc orders forms, amongst Lego Catalogue order forms (unfulfilled, I must admit!), but nothing from Tandy. I saw this for sale and new it needed to be preserved!

SALE ENDS CHRISTMAS EVE, 1994.