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Hidden XYZZY in printer firmware


I have worked with United Barcode Industries "UBI" programmable bar code printers for many years. UBI was bought by Intermec in the 1990's and Intermec was bought by Honeywell a few years ago.

These printers use a basic-like language called Fingerprint. It is interactive or interpreted.

There were "SYSTEM" commands of the form SYSTEM and a number in the interactive part and SYSTEM 1138 had some special meaning. I'm betting the 1138 came from THX 1138.

SYSTEM 0, SYSTEM 10, SYSTEM 20 and SYSTEM 40 did things like memory dumps, listing loaded modules, etc. None of this was documented for the developer community.

Intermec came out with what is known as the XP series of printers (no relation to Windows XP) which had faster processors and more memory. These were flash ROM-based machines whereas the UBI printers used ROM chips and battery backed RAM.

I had to see what commands survived in the XP platform and to my surprise in one of the SYSTEM commands I received the prompt "Enter Meta Guru password:"

Gee, were my Amiga days coming back?

One brief flash of lightning later I entered XYZZY and the printer responded with "Meta Guru mode ON."

After rebooting the printer I entered XYZZY in Fingerprint interactive mode and the printer responded with "Nothing happens."

It's still there to this day on the latest printers.

— Harry Manolopoulos
XYZZY in orbit


"I work on software for small satellites here at Goddard Space Flight Center. On our current project, we needed a 'NoOp' command to be used to verify the uplink/downlink path without changing the state of the satellite. Of course, we couldn't resist calling the command 'XYZZY,' with the response from the satellite decoded on the ground as 'Nothing happens.' So far no one has complained about our little joke." — Mike Blau
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XYZZY does Windows


There's a cheat code for Windows' "Minesweeper" game: type xyzzy, followed by ENTER and the right SHIFT key. Then a tiny dot will appear at the top left corner of the screen that will change color depending on whether the cursor is over a bomb or not.
'Nothing happens...'

Data General's AOS/VS operating system had an undocumented command named "XYZZY." In the original 16-bit version, the response was: "Nothing happens." In a later 32-bit version, this was amended to: "Twice as much happens."

XYZZY on the road


A number of people in various states have personalized license plates "XYZZY." For one example, see http://xyzzy.com. Do you have an XYZZY license plate? Let me know!





Everything you ever wanted to know about
...the magic word XYZZY


The term 'XYZZY' from the Crowther and Woods Adventure game
"...If you use guessable [passwords] like XYZZY... my 12-year-old daughter could be reading your messages inside a day." — Martin Heller, Windows Magazine, July 1, 1994.
has propagated widely throughout both academia and the computing community. This nonsensical string of consonants is still a part of the vocabulary of many who participated in computing's earliest days.

You find mentions of it everywhere. 'XYZZY' (along with other phrases from the game such as "...you are in a twisty maze of passageways, all alike") can be found in computer documentation, classroom discussions, and in many other surprising contexts.

Origins of XYZZY


But where did XYZZY come from? Is it totally a nonsense word, or was there some hidden meaning? There are two stories on its origins.

Bernie Cosell, a friend of Crowther's at the time Adventure was originally coded, says that he was unaware of any special meaning for the word:

"Will Crowther says he made up the term out of whole cloth when he was putting ADVENT together....

"As for 'out of whole cloth,' I meant just what the idiom means: he devised this little pseudo-puzzle and needed a magic word to make it happen, and he just made one up. It has no antecedent nor is it an acronym or anything like that."

XYZZY: a mathematics 'in-joke?'


But Ron Hunsinger believes there is a more meaningful origin to the 'XYZZY' word:

"[XYZZY is] taught by math teachers the world around as a mnemonic device to remember how to do cross products.
"When I first played Adventure, finding 'xyzzy' in it was like finding an old friend in an unlikely place. Or an inside joke." — Ron Hunsinger

"'Cross products?' you ask.

"Indeed. The cross product of two three-dimensional vectors is the vector whose length is the area of the parallelogram with the two given vectors as adjacent sides, and direction perpendicular to the plane of that parallelogram.

"There is a 'simple' formula for the cross product. If A = B x C, where A, B, and C are the vectors (Ax, Ay, Az), (Bx, By, Bz), and (Cx, Cy, Cz), then:

Ax = By Cz - Bz Cy
Ay = Bz Cx - Bx Cz
Az = Bx Cy - By Cx
"Notice that the second and third equations can be obtained from the first by simply rotating the subscripts, x -> y -> z -> x. The problem, of course, is how to remember the first equation.

"You do that by remembering the 'magic word,' consisting of the subscripts, taken in order: xyzzy.

"And that, friends, is the origin of the magic word xyzzy. This use of the word was around long before Adventure (or Colossal Caves or whatever name you knew it by) was ever written.

"When I first played Adventure, finding 'xyzzy' in it was like finding an old friend in an unlikely place. Or an inside joke."


Email your XYZZY sightings to webmaster@rickadams.org today!

The Colossal Cave Adventure page
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