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Modding an original PlayStation

I hadn't played one of these since... maybe... 1996 when my neighbour and I got Abe through his quest. I found this unit at an op-shop recently for AUD$40 and couldn't resist.

The first thing to do was a tear-down + clean. Of course, a friend then told me he had a spare modchip for it.. so... why not do a proper job whilst the unit was still open.

In true Sony-style, the units disassemble perfectly easily and are neat and tidy inside.

Once you're down to the motherboard, it's simply a matter of determining where to wire the chip. To do this, you'll need to know which chip you have and which model motherboard. Mine was a Multi-Mode 3 and I installed it onto a PU-23 motherboard. I followed the instructions here.

Flatten the chip so that you can glue it on top of an IC later.

Then just run all the wires with as-little-slack-as-possible. This just means you wont have any issues with wires getting in the way of screws later.

Test when the case is open, test when the case is closed and test again later. When testing, the CD tray mechanism requires the case to be held firmly together so that spacing is correct for laser alignment.

Last time I was in BKK, I purchased a selection of random Japanese games. Pachinko, Abe's A'go go(Odyssey), Myst and Tekken 3. Turns out they all work perfectly.

Abe's A Go Go is actually a random text-replacement version of the english version. The cutscenes are still in english with subtitles.

And then you get a random ticker at the top with instructions for non-english speakers... Anyway... time to go and play the rest.

Amstrad CPC464 Restoration

I was hoping this would be a plug-and-play, but a machine this old was always going to be a challenge. I received this unit as part of a lot with the other 6128s and have finally received a tape to test on it.

From the outside, the item was a little dusty. That white piece, which looks like a pivot of some sort, fell out when I rotated the unit to see underneath. Never a good sign... Either way, I plugged in the unit and power it up (it happily uses the same RGB and power setup as per the 6128). To my surprise, I got straight to the main BASIC screen! To try my luck further, I loaded my demo tape and typed RUN"...

All good so far... then I noticed that only the left spindle was spinning on the tape player. The right wasn't collecting any of the read tape... I had a hunch where it was going......... yep.

Time to pop it open.

Dusty... OK... I can handle that... what I can't handle is a spring (from somewhere?) magnetised to the speaker. The ad-hoc shotty taping-and-soldering was also a little bit of a surprise.

Regardless, looking at the tape player mechanism I quickly found two dead rubber components. The band to the tape counter had perished...

So had the rubber ring that drives the right spindle. This makes perfect sense and explains why the machine tried to consume my tape.

Finding spares

There's a few options online for spare parts. eBay was my first choice and I have the two main belts on the way from Germany. This'll take a while. I actually really only need the band for the tape counter, but it won't hurt to replace the main drive belt also.

The second part is a concern. It's a tight ring and my initial searching has come up with zero results. Might have to head to the hobby shop today and find a car tyre or o-ring. Meanwhile, did someome say o-ring?

Drive 'wheel'

Not having much luck with o-rings, I went to my local hobby store and bought some Fleischmann HS Scale traction tyres (00544001) (actual picture here). I bought 4 in total and just layered them up on the wheel. I was a little worried about alignment as any friction would cause the tape speed to change.

It has seemed to have worked.. but now the main drive belt is slipping. I'm going to assume it's loose and therefore not getting the required amount of traction. More waiting until the next set of spares arrives!

Drive and Counter belts

The set was ordered from eBay and arrived from the UK in good time. As expected, two belts in a bag. Much stronger and more flexible than the belts they were to replace.

There's one screw underneath to remove and then you just slide the belt over the wheels. Make sure you not twist the belt when installing. It's not 'extremely' tight, so it's pretty easy to install.

Read Errors

Back to testing. The tape drive started operating perfectly, so I attempted to load the cassette once more.

Yosh! We're getting somewhere... but then...

Read Error Codes indicate failures whilst reading from tapes. Sometimes this is a dirty head, other times the head is out of alignment. I wiped down the head with an alcohol swab and then started to attempt alignment. Not really knowing what I was doing, I hooked up the audio to 'listen' to the data and twisted the alignment screw until the audio was loudest and clearest.

After a lot of errors, I seemed to have it stable, so I restarted the machine and tried again. It got all the way to Block 11! Then it just wouldn't continue. I hung around until I could make it say 'abba'.

Was the tape dead? All of a sudden I had a hunch it could be the power supply... so I swapped to an old AT power supply... but it didn't seem to be able to provide enough current...

And then I accidently plugged in 12v...

Take your time when playing with old electronics... I've now received the dreaded Grey Screen of Death and that means any of the internal ICs could be toast. I might muck around and try and swap the socketed ones between the 6128... but otherwise... I might have just lost the battle. $%$#%#$%#%.

There's a lot of good information here on over-voltage. Seems I've cooked the lot.

Chips on the board

I'm putting this here in case I ever feel game enough to do a full board chip replacement.

Chip	Purpose	Quantity	Status
AY-3-8912	Sound	1
AMSTRAD 40009	32K ROM; O/S and BASIC	1
74LS145P	BCD-to-Decimal Decoder	1
74HC153P	Dual 4-input multiplexer	4	Found, not ordered.
HD46505SP	Video PPI	1
D8255AC-5	CRTC	1
74HC273P	D FLIP-FLOP	1	Found, not ordered.
Z8400AB1	Z80A 4Mhz CPU	1	Found, not ordered.
74HC32P	Quad 2-input OR gate	1
74HC244P	Octal buffer/line driver; 3-state	1	Found, not ordered.
74HC373P	8-BIT DRIVER	1	Found, not ordered.
M3764-20RS (Or 4614?)	RAM	8	Found, not ordered.
74HCU04	Hex unbuffered inverter	1
AMSTRAD 40010/40007	Gate-Array	1

Barcode Scanner: Cheating in Style.

I picked up a random hand-held barcode scanner from the markets a few months back and it's been sitting on the shelf waiting for a proper reason to exist. Whilst playing a marathon game of Bubble Bobble on the MSX (and losing, we just couldn't beat the boss), I google'd for cheats. They were all enterable via the keyboard on the main screen... but then it occurred to me... A barcode scanner on a PC would be the best way to quickly type in cheats for your game of choice.

The Scanner

This thing is a hand-held model with stand. It's a DataLogic QuickScan QD2100 and the drivers can be found here.

Note that the device will install perfectly well on windows and show up as a HID Compliant Keyboard.

Once installed, any barcodes scanned will be input via a virtual keyboard, along with a carriage return! To fix this, I'd assumed we'd install drivers and configure the device via software. It turns out instead that we'll need to directly configure the scanner itself via programming barcodes. Grab the manual here and browse to page 90. Read the instructions that they've mentioned:

1. Go to page 91 and scan the top programming code.
2. Scan the Set Global Suffix code
3. Scroll all the way to page 291 and scan the 0 code twice
4. Scroll all the way back up and scan the programming code again to exit

Making Barcodes

There's a ton of online sites that'll do this for you. My first hit was Barcodes Inc's online barcode generator. From here, even from the screen, you can zap the codes and test the device. It should all work pretty flawlessly.

Doom

I must admit, as soon as this idea came to mind, this was the game that I thought of first. Yes, it's dos-based and this scanner isn't... but that doesn't stop me from using it under DosBox.

GOD Mode	All Guns/Keys/Ammo/Armor	Show location details
Temporary automap	Temporary radiation suit	Temporary light
Temporary invisibility	Temporary invulnerability	Temporary berserk
Change map detail	Chainsaw	Walk through walls
All Guns/Ammo/Armor

What's Next?

You could use this to automate processes: Run-through an entire game maybe? Play music? Probably nothing at-all worthwhile... but nonetheless still fun!

Reveal MusicSTAR MIDI Piano Keyboard

Picked this up at a local tip shop a while ago for cheapcheap and have finally gotten around to checking it out. It's a short MIDI Keyboard from Reveal, model number MKB02. It turns out the company no longer exists; but Creative did try to save them back in the day.

Anyway, the keyboard is really nice. It has the standard IO: Power plug, power switch and MIDI out. On top you'll find buttons to adjust pitch and octaves.

Mine didn't come with an AC adapter, so I purchased the closest 9v 200ma supply I could find.

I was concerned whilst hooking this up as to the polarity of the plug. Usually you get the little symbol somewhere on the unit to dictate where positive is. Every other MIDI device I've seen lately has positive on the outside... but this does seem to be a Japanese thing.

The best way to solve this was to crack the unit open... it's a keyboard nonetheless, so it probably needed an internal clean anyway!

That last photo is of the IO board. The best bit? The power runs in from the DC jack into a friggen bridge rectifier! Why am I so happy/excited about this? It means the polarity doesn't even matter! It more-or-less treats the input as AC and converts it to its own polarity. How good is that!? All devices should do this.

Anyway, the next step was to simply hook it all together into my SC-55. Of course... it just worked perfectly!