Worklog Famicube ( Famicom disk system hardware and case mod )

[Reiko_VT]

"The Nintendo way of adapting technology is not to look for the state of the art but to utilize mature technology that can be mass-produced cheaply."

Gunpei Yokoi was quoted as saying that in his book Yokoi Gunpei Game House. It was a philosophy that helped shape the Gameboy and was carried on to numerous future Nintendo consoles like the Wii or DS where well-understood and mature technology was used in new and novel ways. I'd like to believe this way of thinking was even used on Nintendo's earliest console add-on, the Famicom Disk System.

It was introduced in 1986, just as Nintendo fever had taken over Japan and was just starting in North America. The add-on used floppy disks - a well-understood format by then - to contain their games and boasted holding up to 128kb compared to the much smaller cartridges at the time. To entice gamers, disk games were sold at a cheaper price than their cartridge counterparts, and could even be rewritten at certain kiosks in stores. For a while, Nintendo seemed to think that floppies really were the future and released some of their biggest titles on the format like Metroid, The Legend of Zelda and Kid Icarus.

Don't copy that floppy!

Let's take a closer look at the floppy disks Nintendo used as well. Nintendo chose to partner with Mitsumi and use their Quick Disk format, which had previously been used on Roland and KORG sequencers to store tracks. Each of Nintendo's disks was branded with their name stamped on the bottom which served as a rudimentary form of copy protection since the stamped name needed to fit into an opposite piece inside the drive. The discs were also very colourful too and came in colours such as a bright yellow or a softer blue.

The disks were also unique since they were also in a sequentially read format instead of a random access one. Simply put, Nintendo's discs acted more like a tape cassette instead of the floppy disk we all know from earlier home computers of the era. The data is contained in one large spiral, and the read head only needs to go from one end to another instead of seeking it out. This means there are less complex mechanics inside where the head needs to know where it is in relation to where data is stored.

Credit: Eurogamer

The floppy drive was then interfaced with the console using a RAM adaptor. It contains a special connector to fit in the cartridge slot, a small amount of additional RAM, along with an ASIC that handles the serial data and also some sound processing. There was a planned and added-on port to the RAM adaptor that was never used, perhaps it was intended to link consoles together for multiplayer like the Gamecube or Xbox could do.


Nintendo was also surprisingly forward-thinking with their Famicom Disk System. Since data like saves and high scores could be stored on the disk, the company thought of how to share them in unique ways. One example was a competition held with Mario Golf, where disk owners could go to the kiosk they purchased the game from and fax their high score to Nintendo and receive a special cartridge from them!

credit Android Arts

An Imagined Future

Unfortunately, as forward-thinking and unique as the Famicom Disk System was, technology becoming cheaper and piracy ultimately spelled the end of the add-ons life. Ghost 'N Goblins was released shortly after the add-on and boasted a 128k ROM on a cartridge format thanks to falling prices in storage. Piracy was also rampant for the system, and while Nintendo released revisions of the hardware to try and thwart pirates, it was ultimately a losing game. The system still went on to sell 4.4 million units and is still loved by many for the games it introduced.

Though, what if Nintendo had kept with the Famicom Disk System and their idea of storing games on floppy disks?

Arne, a self-taught artist, imagined such a future where Nintendo had partnered earlier with Commodore to try and branch off into the home computer market as well, but like many of Nintendo's joint hardware projects, had eventually split.

I was really enamoured by Arne's thoughtful designs and how he also went through several concept arts and revisions too. Everything was detailed and he documented his thoughts and philosophies well. I really admire his work, and one day I want to hone my skills to do what he's capable of. However, for now, I'll try my best to make his concept art a reality using my skills in prototyping, electronics, prop making, and 3d printing. Shrinking something down in size to be a cube won't be easy, especially considering that there's an entire drive mechanism to contend with if I'm using actual hardware.

 

[Wesk]

Your concept art is absolutely killer, I love it.

[edit]

Just saw it wasn't yours, statement still stands however.

 

[Reiko_VT]

Honey, I shrunk the Nintendo!

If I wanted to make Arne's concept art real using actual Famicom hardware, I needed to think hard about miniaturization and where space could be saved. Earlier revisions of the Femidom's main board were thankfully small and had a combined voltage regulator and RF modulator that was separate. By doing a composite mod and making my own power PCB for the drive and main board, I was able to save a huge amount of space. I chose to do it in an older point-to-point style for testing as well, which looks really artistic up close. I'll likely spin up a small PCB that can be soldered on under the points where the mod needs it.

Space Hog

The next obvious part to go was the large custom connector to make the horizontal PCB of the cart connector interface with the vertical cartridge slot. It was an absolute beast measuring 45mm tall with 60 pins made out of folded metal around an injection moulded spacer and holder. The connector seriously put up a fight with desoldering, and needed a combination of a desoldering iron, wick, low temp solder and a hot air rework station before it wanted to come off from the PCB. Keen-eyed viewers can likely see that even though I tried my hardest to be clean and careful, one trace did rip off in the process. Thankfully a short jumper wire was the only thing needed to restore it. I then added simple male pin headers with the idea of using a PCB to shift the adapter PCB more centre of the main board. In essence, I was making a little PCB sandwich that was a lot thinner than the original hardware.

I like to add PCB artwork where I can with projects, it can really make things feel more personalized or professional. My cartridge shift PCB seemed like the perfect blank canvas, so I added a small logo I noticed on Arne's concept art. PCB artwork is done by taking advantage of how circuit boards are made and how they have plate copper and several different kinds of coatings that define where solder go and also label where parts are. This board has female header pins on one side and then a card edge connector that matches the pitch of the cartridge slot.

While there could have been more elegant solutions to make it thinner still like reverse engineering and making a revised PCB, I thought this was a good balance between saving height and working within my own skills.

Here we can see the final stack up. The entire assembly measures 42mm tall, which is 3mm less than the original cart connector by itself! With that, the Famicom side of things has been reduced in size the furthest I can take it. I now have to go on to the disk drive to see what can be shrunk down.

 

[mknrls]

big fan of Arne (Android Art) concepts and excided for you to bring it to life!

 

[Stitches]

 

[Reiko_VT]

Reverso

Opening up the disk drive, I was surprised at how empty it was once the battery compartment was removed. Thankfully that makes reducing the drive side would be very easy since there's only one PCB to adjust! The PCB on the left is a simple power board that works as a voltage regulator and controller for an LED and motor. I'm partially lucky as well since this is an earlier revision, Nintendo later went on to make daughterboards for the PCB and even whole new PCBs to add piracy protection.

Since the power board is only single-sided and uses jumpers for a few connections, reverse engineering was simple and non-destructive too. Using a photography rig that I built, I took a top-down image of both sides and then adjusted for any lens distortion. This let me overlay both sides over each other and see both at the same time by using Photoshop and a bit of layer blending. I then added more translucent colour layers to the image to figure out the connections and the large copper pours. After making a rudimentary schematic I went into an electronics design software and started to build a final schematic that I could eventually make into a board. The whole process took about a day, and even if it was my first time trying to reverse-engineer something, it was relatively simple.

The board files I sent out to a PCB manufacturer came back after a week, and after some testing, everything worked perfectly! Here's Nintendo's version on the left, and mine on the right. I'm sure if I used equivalent modern parts for some of the transistors and chips, the resulting circuit would have been even smaller. I eventually changed out all the connectors as well, since the older and proprietary ones took up a lot of space compared to modern board-to-wire connectors you can get from companies like Molex. I'll have to make my own cables in the future, but it's something I'm well versed in and even enjoy sometimes!

Now with things shrunk down as far as I could personally get them, I could start to figure out how to put everything together in its new form factor. I took some influences from how older computers used to be built for my construction methods and surrounded the Famicom PCB and drive inside a metal cage for rigidity. I have some metalworking skills, but I'm not great at sheet metal or being accurate with it, meaning it'd be better if I outsourced them. Companies like Laserboost can easily produce metal pieces by taking files produced by CAD software, and I used them to make the drive cage. I'm not affiliated with them, but I have used their services to build things like custom keyboard plates and found they have a good service and make accurate parts as well.

 

[Reiko_VT]

Then, after a short wait for the parts, I could get some product shots.

 

[Stitches]

I do like me some metal forming

 

[Reiko_VT]

Cables and 3D-Printing

Now with the inner frame in hand and with the majority of PCBs made, I could get on to one other way I could make this build smaller. Nintendo used big and bulky connectors both internally and externally, which makes sense, the connectors on the outside were ones that kids needed to handle and needed to be easy to grab! By using smaller connectors and some careful cable management, I was able to save some more space internally. Now the most size-determining component is the Mitsumi Quick Disk Drive and a power connector at the back of the Famicom motherboard. I can and will be changing the back connector on the Famicom with a PCB of my own design to break out the power, audio and video a little better.

With how the whole project progressed, I was pretty confident that I could start 3d printing the pieces. I'm using PLA since it's easy to print and comes in a wide variety of colours, which came in really handy when I was trying to match that distinctive Famicom red! There are a few stories of how that red came to be, some say it was the then president's favourite colour, some say it came from a pack of cigarettes, and others say that it was from a scarf the president of Nintendo wore pretty often. Whatever the story may be, the specific red they used was RAL3032 - otherwise known as Pearl Ruby Red - and filament makers like Filamentum and Colorfabb offer it!

For the curious as well, the whole Famicube recreation is 16.8 cm³ or 6.6 in³. The drive itself is 4.5cm 14.5cm x 12cm (height, width, depth), so I think I managed to get it as compact as I can!

 

[thedrew]

I'm really digging your professional photography, really takes this worklog to the next level!

 

[Reiko_VT]

I wanted to share a brief progress update! The 3d printed shell is done, and I'm really happy with the aesthetics! It was a little bit of a struggle to get the top on since some of the cables have a clearance of only 2mm or so. I have an idea of how to fix that issue though, so stay tuned!

All that's left now is adding decals to the case, making a breakout board for the controllers, and making a custom controller for the build too!

I'm also figuring out a small set or location to take some photos with my SLR when the build is done too.