TeensyROM!

So, you have tons and tons of games and music and apps on your TeensyROM. Unfortunately, you’ve probably discovered the hard way that a folder with hundreds of files in it takes quite a bit of time (relatively speaking) for the C64 to index and present, right?

If that doesn’t bother you too much, but you do have favorites you want to be able to access more quickly, and you still enjoy the physical aspect of managing your media, you could always use NFC tags to launch things instead.

Right, I heard the record scratch from all the way over here, so let me explain a bit:

You know NFC cards and tags? No? Do you know Amiibo, the little collectible figurines that you can tap on your Nintendo Switch to interact with your games in various ways? Those are using a technology called NFC, short for Near-Field Communication.

It’s really little more than a coil antenna connected to a teeny tiny little chip that stores a serial number or in some cases, whatever the user writes to it, up to a certain number of characters. The most basic format, like Amiibo uses, is really just a statically-set serial number that a sensor pad can read, by inducing a very small current into the antenna, and reading the resulting pulse that is sent back out.

This is the technology behind the tap-to-pay system available through your phone, or debit/credit cards.

You can get your own NFC tags, fobs or cards from just about anywhere online, and the reader pads are also readily available for cheap, so it’s pretty easy to amass your own collection.

Why would you do this? Okay, so look at it like this: all those Amiibo figures do is look neat, cost a lot, and unlock some unique character feature or item in a game when its contents are read, right? You can do the same thing with a generic tag you make yourself; the only really unique and difficult-to-replicate aspect of those figures is their character designs that gives them their collectability. That’s it. So now that you know you can use NFC tags as a kind of trigger, how cool would it be to be able to tap a card on a reader, and your computer reboots itself and automatically loads a specific program or game? Moreover, what if this happened almost instantly, any time you tapped a new card, regardless of what was already loaded and running??

That’s what TeensyROM paired with the TapTo (Zaparoo) system brings to the table. Tap a card, and (after you’ve done the basic initial setup) the cartridge will trigger a reset on the Commodore, while the Teensy’s cartridge emulator is pointed to a different specific program or game stored on a SD card. The result is a blink-and-you’ll-miss-it swapping of running programs simply by tapping a card, tag or fob on a reader!

You know what, here. See it in action for yourself, instead. You’ll get the idea quickly. 🙂

I know, right? 🙂

So the two components are theTeensyROM, and the NFC reader that lets you make your own virtual cartridges to swap between programs, connected to the TeensyROM’s USB port.

The reality is that tapping the NFC card is really doing little more than automatically selecting a crt or prg file that’s already on the TeensyROM, and then rebooting the C64 with that virtual cartridge file now being “active” as the first thing the computer sees on startup. However, it’s a cool little way to keep that sense of using physical cartridges, floppies or cassettes without the costs of increasingly-rare media and load times, and risks of losing something precious or irreplaceable with those old formats. Keep that old worn game cassette you’ve been holding all these years intact, just load the program from something else instead while you preserve the actual original media that introduced you to this world of miracles, instead.

Now, to be clear, you can actually use the TeensyROM by itself. You do NOT need the NFC reader add-on for it to be able to load cartridge files you select from its own built-in menu. However, you will still have to reach around to the cartridge to tap the reset button to back out of a program/game, or reset the Commodore manually with the power switch itself (like dad always did) or with whatever other reset mod you’ve built in. All the NFC portion does is make it easier to hold something physical in your hands and flip to a desired program more quickly because one card=one program, so once you’ve set it up and put a label on it, that card might as well be an instant-load disk itself (though no, the programs do NOT load from the card. They come from the SD card on the Teensy; the NFC tags just tell it which program to reset-and-run when tapped).

It’s just a little bit of “let’s pretend” that will undoubtedly conjure those childhood images of floppies scattered all over the desk or carpet, only now there’s no risk of dad losing his shit and paddling you good for ruining the software collection. 😀

Let’s put one together!

NFC Reader for TeensyROM: https://github.com/SensoriumEmbedded/TeensyROM/blob/main/docs/NFC_Loader.md

As noted in the features above, the TeensyROM is also capable of providing a MIDI interface as well, so you can connect a MIDI controller or keyboard to the USB, and use it to play music with the Cynthcart program, to start.

YouTuber Lukhash used one to connect an electric guitar for this tune:

You can also find CCGMS in the Utilities, and go exploring the many Bulletin Board Systems (BBSes) still being run out there! Yeah it’s basically telnet rather than the old-school dialup, but can we all agree that the fun of playing around on those boards back in the day had nothing to do with dealing with the downsides of old-school dialup connections? Exactly how exciting was it to connect to some well-designed BBS, wait for the awesome artwork to actually finish drawing its slow way across your screen, then for the connection to just drop before the menu got to display?? Nah, I like experiencing the Commodore nostalgia at 38,400k instead. 😀

08/22/2024: I decided to see how well my NFC “drive” enclosure design will work out in its current form. I feel like it’s pretty much finished, but now need to see how things fit together to determine if further adjustments need to be made. My 3D printer is awaiting some hardcore tuning and adjustment work, so I’ve ordered out for the prints instead. Here’s hoping for nice results!

9/14/2024: So the enclosure arrived, and while there were some design issues I need to address, the overall effect is definitely what I was looking for! Hot glue gets around the fastener placement issues, to the point that I think I can leave the screws out of the interior altogether, and just adhere to receiver board to its own little platform inside, instead.

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