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VTech Socrates – Educational Video System

This poor unit was found in a box of random junk at the local tip shop. It's a VTech Socrates educational computer based of the Zilog Z80 chipset. It seems to have standard RF input/output, but someone has gone ahead and wired in their own antenna cable? The couldn't be bothered finding a screw-to-plug antenna adapter?

After working out how to tune an analog signal on my TV, I applied 12v... A very slow screen started to appear! Is that Johnny-5?

Giant Bomb's Review of the system doesn't give a favourable view. It seems that the unit had a 'very short life' due to slow graphics/animation and little software being available. It does mention the extra items, such as the mouse and touchpad... of which I've been unable to find physical examples of.

The expandability is obvious in the above photos.. you can see the Cartridge slot and Expansion slot on either side of the motherboard.

Composite Mod

Just like most items that come across my workbench, I don't believe there's any need to keep them as RF-output. RF modulators were a requirement back in the day as TVs only had RF-antenna input. RF was fine for terrestrial signals, where a cable would be slightly inconvenient! Not so when the unit producing the a/v output was located right next to the TV. Once composite signals started appearing on TVs, there was absolutely no need to convert to-and-from RF. Of course, it was already too late for devices that only had RF output.

The RF modulation circuits in these units usually consist of a silver modulator unit and the inputs to this are more-or-less the exact composite signal required. Removing (or bypassing) the modulator is an easy step and RCA sockets can usually be installed somewhere in such units. Here's how to do it on a Famicom.

Anyway, back to the Socrates. The original owner had already trashed the RF modulator, so I chose to remove it. The ribbon that runs to it is pretty hard to work with, but I spliced into it and ran the wires to RCA sockets instead. I provided both right and left audio plugs, but they're both wired to the same single mono audio output signal.

From there, the picture was clean and crisp. The sound too! Of course, it's always hard to take photos of CRTs.. I tested it on the BeoVision MX 7000.

And.. about that refresh rate... this was it trying to draw a spelling game over about 12 seconds...

I was presented with R A I O D as a scambled word challenge...

Nope.. it doesn't know what RAID-0 is.

Cartridges

A short time googling found me at Team Europe's blog post regarding the innards of a VTech Cartridge. How cute are they? Designed after a floppy drive, of which you jam in the side of the machine when it's turned off.

The insides look as simple as an EPROM on a board with a single capacitor? I was about to ask for the board pinout, as it seems there's one or two traces under the chip, but then I came across their post from this year regarding their multicart! Hah, it's exactly as expected... an EPROM on a very simple circuit board. They've used an EPROM that's 8x too large, to fit 8 images (all games ever produced) on the chip... you then select the start offset with the dipswitch.

I've sent out a message requesting one... let's hope they're still available!

Setting up a Palm OS/Sony Clie Development Environment

Why would I do this in 2019? Because fun! I found this unit in Malaysia and wanted to try and control my BeoVision MX 7000 with it. Turns out that none of the software I tried wanted to work! Actually, even at first, I had trouble trying to install the applications. Everything wanted HotSync? Muhahaha... I remember those old days! The I found this forum thread where everyone is just like "duh, copy the files to the LAUNCHER folder"... and so, I did.. and so, well, the apps worked... but that was about it.

Of course, before even getting the MS to read, I needed to find a reader that would support it. There seems to be (at least) three types of MemoryStick and this thing uses the very first version. I tried my standard card-reader that I use constantly for my camera's SDHC card, but this wouldn't read the MS at all. Fortunately, there was an older reader (with CF slot!) in my box-o-junk that happily read the MS. Of course, it then didn't read the SDHC, so there was a lot of juggling to get data transfered.

So, the apps.. OmniRemote Pro was the closest to work. It supported learning and even supposedly 'recognised' my fake BeoVision remote. But no attempt to send the signal back to the TV worked.

At least I now knew how to run external programs... let's write one!?

Cygwin + PRC-Tools

GCC for Palm OS (or PRC Tools) is a self-contained compiler that sits on top of Cygwin. It even comes with source code examples. I've recorded the steps below to set up a functional development environment... the code even worked on the Sony!

Firstly, download Cygwin 32-bit Setup from here. 64-bit won't work! Once downloaded, run setup-x86.exe -X from the command line to allow unsigned packages. Choose a local mirror and then add http://prc-tools.sourceforge.net/install in the User area below. After adding, both mirrors will be selected... hit next. Search for prc and check the selections...

Make sure you then also choose to install make and pilrc. Hit next and let it all install. Whilst that's happening, go and download the Palm OS SDKs from here. Yes, you'll need to download the whole lot (Download as Zip from the root github folder), but it's not that big. Once downloaded, extract the contents to a new directory called c:\Cygwin\PalmDev.

If everything has been done correctly, then open the Cygwin Terminal and run palmdev-prep.exe.

$ palmdev-prep.exe
Checking SDKs in /PalmDev
  sdk-1         headers in 'include', no libraries
  sdk-2         headers in 'include', no libraries
  sdk-3.1       headers in 'include', no libraries
  sdk-3.5       headers in 'include', libraries in 'lib'
  sdk-4         headers in 'include', libraries in 'lib'
  sdk-5r3       headers in 'include', libraries in 'lib'
  sdk-5r4       headers in 'include', libraries in 'lib'

When GCC is given no -palmos options, SDK '5r4' will be used by default

Writing SDK details to configuration files...
...done

Yes, we got it installed!... Now grab the code from this link and try and compile it...

$ make
m68k-palmos-gcc -O2 -Wall -g -c -o helloworld.o helloworld.c
      3 [main] m68k-palmos-gcc (11268) C:\cygwin\bin\m68k-palmos-gcc.exe: *** fatal error in forked process - couldn't allocate heap, Win32 error 487, base 0xEF0000, top 0xF50000, reserve_size 389120, allocsize 393216, page_const 4096
    915 [main] m68k-palmos-gcc (11268) cygwin_exception::open_stackdumpfile: Dumping stack trace to m68k-palmos-gcc.exe.stackdump
      1 [main] m68k-palmos-gcc 1983 dofork: child -1 - forked process 11268 died unexpectedly, retry 0, exit code 0xC0000142, errno 11
m68k-palmos-gcc -O2 -Wall -g -o helloworld helloworld.o
pilrc -q -ro -o helloworld.ro helloworld.rcp
build-prc -n helloworld -c helo helloworld helloworld.ro

That error looks a little scary... but whatever... let's see what happens?! Noooo waaaaay....

We got an icon! Does it work?

Look at that glorious string of redundant text! Next I'll come back and write actual source to talk via IRDA. Maybe even to my Matsucom On Hand PC?

Sony Clie PEG-SJ30 (N50)

I picked up this Sony Clie at the Chinatown fleamarkets in Kuala Lumpur during the last trip and have finally gotten around to testing it. As expected, the battery was dead-flat, so I didn't have much hope. Also, no cables or other accessories... so how to bring it back to life?

I found a standard rechargeable 3.7v battery after unscrewing the back panel. I say 'standard', as this voltage seems very popular for small rechargeable devices! I don't have any rechargeable batteries on hand... but then remembered something else I'd picked up in Malaysia!

The current battery was dead, so I snipped the connector and wired it into the drone battery...

Niiiiice! It works! But this isn't a good answer... the battery is too big for the unit. Off to Jaycar I went to pick up a GT4195 battery. This one happens to be the correct voltage and fits perfectly!

Off the shelf, the battery came with zero charge! That's pretty unusual actually... I don't think I've ever bought a rechargeable battery from anywhere and have it have absolutely no juice. This straight-away presented a problem... I have no charger for this PDA, meaning that I can't seal the battery in and charge externally. So, I had to wire in another plug to use the drone charger to keep this thing going. Not 100% awesome, but it's a workable solution.

After a full charge, or so the usb-charger reckoned with its red light off, I gave it a quick test. All worked perfectly with this smaller battery!

I'm also surprised it accepted the year 2019!

Before I knew it... we were at the home screen.

Meanwhile, it has a Memory Stick in the slot... a quick check found the following...

Joy! Time to format that and get some IRDA software to try and control the BeoVision MX 7000.

Iomega 1GB Jaz Drive Power Supply

Picked this little beast up from the flea markets recently. It came with 2 disks and no power supply! I was so excited to see a random pile of SCSI junk at the markets, that I forgot to check if everything required was in the bundle when I picked it up.

The power plug on the back looks like a PS/2 cable with a lower pin missing. Why do it for? Of course: proprietary power means you need to contact their service desk when you need a replacement... or do you?

I started hacking up a spare PS/2 extension cable and got it to fit!

As I was rummaging for a compatible brick that could supply both 12v and 5v, I found that I already had a "ps/2-style" power adapter in my box-o-shite. It had exactly the right pinout, with voltages all in the correct places, but the extra pin was stilla an issue...

I grabbed the sharpest pair of snips in the toolbox and quickly hacked the plug into submission. With that pin clear, it was time to test...

Noooo waaaaay... it also worked perfectly when on a SCSI card. Nothing interesting on the disks though!

Adding more RAM to a Toshiba Satellite 300CDS

Picked this up recently and loved the design and specifications. It needed more RAM though, so I started unscrewing it to find the relevant slot. Turns out there's minimal effort needed... not even a screwdriver! Usually you get a panel underneath with a cute RAM icon, or somesuch, but there was no such thing on this unit.

Instead... there's a lever-point on the right-hand-side of the unit, on the edge of the 'bevel' that runs along the top of the keyboard. Once popped out, the keyboard nicely lifts up and you have full access to the RAM slot.

The trusty box-o-crap was emptied and all laptop RAM shown. 4 were a good fit, but all SDRAM. Unfortunately this unit only accepts EDO!

Matsucom OnHand Wearable PC

Saw this on eBay... no one else bid on it? Are you serious? It's one of the first smart watches! It was also one of the first to have its own software development kit.

Totally reminiscent of a Casio, it's a chunk Matsucom OnHand PC which is actually the american clone of the Seiko Ruputer. In the package is a whole lot of documentation, software, the watch, a docking station and a cute little extra battery holder.

I expected CR2032 coin cell batteries, but it turns out it wanted CR2025s? I went off to find some...

Using it

I was immediately presented with "Fatal Error" after turning it on. The default action is to try and open "My Computer", so I assume that area of memory is crap.

I booted my Windows 98se VM and plugged through the serial port. We were connected in no time and I was straight-away warned that the internal memory was rubbish. A quick format later and I had a connected watch!

The file browser kept throwing an error that shortcut.ini was missing, so I created an empty file in the relevant directory, which successfully shut the error up. I wonder what software I can put on this thing?

The community still exists!

There's a whole raft of software at PC On Hand. This website actually has all the information you could ever want. If you're bored, it seems you can even convert movies into short animations to play on your watch.

I quickly downloaded the fishtank and copied it to the watch with zero effort required.

Yup... Fish. Worked nicely... EXF seems to be the compiled executable for the watch and it was seen as such in the file browser after copying. It's then a really quick navigation on the watch itself and, before you know it, you've got a mini aquarium on your wrist!

Software Development

PcOH-C For Windows is here, but they want you to register to download. I tried to do so, as I'm a legitimate human and was happy to see what random emails they wanted to send. Regardless, the signup process is dead... so the file is out of reach... or is it? I changed the URL from .asp to .zip and, you guessed it, the 1.6mb of glory downloaded. Here's a version just for keep-sake. The SDK is required, and that URL doesn't work either... so here's the entire product CD.

There's a few samples in PConH and I quickly compiled the first one. MAIN.EXF was created and I was able to upload it to the watch straight from the IDE. Before that though, the IDE has an emulator in it! You don't even need to deploy to your watch to test!

I copied it to the watch anyway...

It also executed perfectly fine and, as expected, the relevant indicator popped up when pressing the joystick directions. The best part was that you can do diagonal actions as well... might come in very handy for a game!

What's next? I think this watch deserves a mini-model-railway.