FifteenTwenty: now on Fontlibrary and github


Use it / download it here: FifteenTwenty on
Download it / fork it here: scruss/FifteenTwenty on github
Local copy: (268K; includes FontForge sources)

FifteenTwenty: Commodore 1520 plotter font

FifteenTwentyFor the impatient: download (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:

Commodore 1520 printer plotter (adjusted).jpg
Commodore 1520 printer plotter — by Oguenther (Dr.Guenther). – This file was derived from Cbm1520-2.jpg: , Public Domain,

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+0060    `    GRAVE ACCENT
U+007C    |    VERTICAL LINE
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.)

Building the Stick of Joy

Update, 2017-06: I’ve updated the plans so you shouldn’t need to spend  time sanding things to fit.

Not-even-remotely over-engineered retrogaming joystickTracking down old Atari-style joysticks for retrogaming can expensive, and it’s hard to tell if you’ll get something reliable. So I made one for less than the cost of a used stick on eBay.

To build this, you will need:

  • 8-way joystick , or any stick compatible with the industry standard Sanwa JLF-P1 mounting plate. This has M4 holes at 84 × 40 mm.
  • Two concave momentary arcade push buttons. In my built, I used an older design that’s much taller. You could make the joystick box shorter if you used these snap-in buttons.
  • DE-9 (DB-9) Female Socket Connector
  • Terminal block, with at least seven connectors. You’ll likely want more, so this 12 position screw terminal block should work.
  • 4× M4 countersunk (oval head) machine screws with nuts and lots of washers. You’ll need washers to act as spacers between the box and the joystick mounting plate. This allows the joystick’s dust washer to move freely.
  • a couple of metres of 8-core stranded signal cable
  • hookup wire and spade connectors for building the button harness.

The case is made from 6.4 mm high quality plywood, using a template generated by BoxMaker.  The external dimensions of the box are 163 mm x 143 mm x 83 mm. I haven’t included any kerf width in the design, so the edges should fit together easily for gluing.

Joystick box plan for download: joystick-box-201706.svg (SVG: best in Inkscape); joystick-box-201706.pdf (PDF).

If you want to make your own design, here’s the top plate plan: joystick-box-top-201706.svg (SVG); joystick-box-top-201706.pdf (PDF).

The basic DE-9 pin wiring for Atari-style joysticks goes like this:

1 — Up
2 — Down
3 — Left
4 — Right
6 — Button
8 — Ground

There are many variants that add features to this scheme, however. If you’re building for a specific computer, Tomi Engdahl’s Joystick information page has the details.

Many thanks to Andrew Horsburgh for the use of Protolab‘s laser cutter.

amiga: blank hdf images

I’m trying to get running an Amiga again, to see if I can remember what was rocking my computer world twenty years ago. I want to run that code, swim with the Fish disks, and generally muck about with what was my life back then.

Emulation is interesting. Variants of UAE (which came with an Amiga Forever CD set I bought in 1997 or so) rule the roost. Quality is variable – on Windows, WinUAE is very comprehensive, even making grink-gronk noises as the floppy spins. On Mac, E-UAE is really not worth the bother kinda okay – it doesn’t want to emulate anything above a 68000, and falls over quite often but has decent sound. On Linux, it’s plain and stable, and I happen to have an old Thinkpad going spare I can dedicate to emulation.

I would have expected all the old disk images to be readily available for download. It seems that the current owners of the Amiga name (this week, at least) still cling on to the old IP as if it has real value. The Amiga games market (which was the market) basically collapsed with Commodore in 1994. I really wonder who is buying the PowerPC based, vastly overpriced new hardware? For now, I’m relying on good old-fashioned torrent sites for my data.

I want to emulate two machines; the A500 I had for all my cringe-worthy magazine writing running Workbench 1.3, and a fast thing maxed out with all the processors and RAM I never had, probably running 3.1. While I did have Amiga[D]os 2.04 (can’t remember if they’d dropped the D by then), it wasn’t the main focus of my interest by then.

The biggest problem I have is getting hard disk image, even blank ones. UAE is picky. Here are a couple I formatted under WinUAE, both blank.

I wonder if they’ll work under 1.3?

Update: yes, they should. I formatted them FFS under AmigaDos 1.3.