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Photo taken at: Protolab Makerspace

For the impatient: download FifteenTwenty-master.zip FifteenTwenty-Regular-OTF.zip (or more options …)
Updated: now with all ASCII glyphs!
Update, September 2016: this font was officially squee‘d over by Josh “cortex” Millard on the Metafilter Podcast #120: Hard Out There For A Nerd. I had the great pleasure of meeting Josh at XOXO 2016, too.
The Commodore 1520 was a tiny pen plotter sold for the Commodore 64 home computer. It looked like this:

I never owned one, but it seems it was more of a curiosity than a useful product.
From a nerdy point of view, however, this device was rather clever in that it packed a whole plotter command language, including a usable font, into 2048 bytes of ROM. Nothing is that small any more.
Thanks to the epic efforts of Jim Brain and others, this ROM is now archived on Project 64 Reloaded. Looking at the code, I was struck by the elegance of the encoding: it packs a full X-Y plot instruction in one byte.
Based on my work with the Hershey font collection, I thought it would be fun to extract the coordinates and make a real OpenType font from these data. I’m sure others would sense the urgency in this task, too.
Since Commodore computers used a subset of ASCII, there’s a barely-usable set of characters in this first release. Notable missing characters include:
U+005C \ REVERSE SOLIDUS U+005E ^ CIRCUMFLEX ACCENT U+0060 ` GRAVE ACCENT U+007B { LEFT CURLY BRACKET U+007C | VERTICAL LINE U+007D } RIGHT CURLY BRACKET U+007E ~ TILDE
I’ll get to those later, perhaps.
Huge thanks to all who helped get the data, and make the bits of software I used to make this outline font.
(Note: although the Project 64 Reloaded contains some extraction code to nominally produce an SVG font, it doesn’t work properly — and SVG fonts are pretty much dead anyway. I didn’t base any of my work on their Ruby code.)
Nope, no clue. Here’s the source if you want to play with it in a vector drawing program.
Update to the Update (2026): Forest City Surplus in London, Ontario still has them (as of 1st March 2026) in stock at $5: Sayso Mini Scrolling LED Message Boards, Digital Business Signs. I scored a few, and may actually finish this someday …
Update: I thought I’d work out this audio format some day. I haven’t yet, and since I no longer have the hardware, likely never will.
You may still be able to get Sayso Globord programmable LED signs in surplus stores. It’s a 7×24 LED scrolling sign that you can program with a lightpen or with audio input.

The unit comes with no software, but has a link to https://www.dropbox.com/sh/q1q9yhahwtblb23/AACpMeXQjYyD8ZWC-65vNgcxa printed on the box. (Link is still active in March 2026!). It’s an archive of the programming software, manual, and canned audio files for a whole bunch of standard messages. Here’s an archive if the dropbox link goes away: SaySo.zip
If this page goes away, the software is now on Internet Archive: SAYSO Globord LED Sign archive
The audio files used for programming the display are clearly FSK-encoded, but I haven’t quite worked out the relationship between the tones and the display bits. Here’s what I’ve worked out so far:
The editor runs nicely under DOSBox, so you can experiment and save samples as WAV files. Here’s a sample display with its corresponding audio linked underneath:

I’m not sure how much extra work I have time or inclination to put in on getting this working, but I hope that my preliminary work will be useful to someone (maybe this person).