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The Lights Keep on Blinken
cavac writes "At the 19th Chaos Communications Congress in Berlin/Germany developers showed their newest developments for the closed-down Blinkenlights-Project. One of the projects was the Blinkenlights Fileserver Project. Members of this team developed a protocol and some tools similar to ftp, which you can use to share Blinkenlights-Movies. Today, a first Beta-Version was released. You might want to check it out. (It also includes the famous Telnet-Blinkenlights-Player).
We are still searching people willing to help us developing this software even more or to work with us on "Phase II": Implementing Soft- and Hardware for a Hardware-Based Blinkenlights Player. This will most likely based on one of Zilog's new Development Kits - the "Z8 Encore!"."
What is Reverse Polish Notation?
When you are at school you learn that different arithmetic operators have different precedence, although that may not be the exact phrase the teacher uses. You are probably given a mnemonic such as "My Dear Aunt Sally" (meaning Multiplication, Division, Addition, Subtraction) to tell you the order in which to do sums. For example, if you are given:
1 + 2 x 3 = ?
you know to multiply 2 by 3 before adding the 1. Early pocket calculators were not acquainted with Aunt Sally, and would evaluate this expression as 9.
Another school-days mnemonic, BODMAS, tells us to attend to the bracketed expressions first, followed by the usual algebraic operator precedence. Brackets (or more properly parentheses) remove any ambiguity about the order of evaluation of expressions. Most complex expressions could not be expressed without brackets, and they are often used in computer programming even when they are not strictly required, simply to eliminate confusion. For example:
(1+2) x 3 = ?
is guaranteed to evaluate to 9, whatever precedence rules are applied (or if the programmer has forgotten them).
The BODMAS rule is applied recursively; brackets can contain other complex expressions which themselves contain brackets, and so on.
In the early days of electronic calculators these rules proved fiendishly difficult to implement in calculator hardware. But calculator designers at Hewlett-Packard realised that a radically different method of defining the arithmetic, invented in the 1920's by Polish mathematician Jan Lukasiewicz (1878-1956) for symbolic logic, could be used to simplify the electronics at the expense of a little learning by the user. In the 1960's that would be regarded as a reasonable trade-off. For most calculator users of the time, the alternative was the error prone practice of writing down intermediate results. The Hewlett-Packard engineers called their calculator logic Reverse Polish Notation (or RPN) in recognition of its inventor.
Using RPN, it is possible to express an arbitrarily complex calculation without using brackets at all. In RPN the simple example "(1+2) x 3" becomes:
3 2 1 + x
Like a sentence in German, all the verbs come at the end. This notation may look strange at first, and clearly if the numbers where entered as shown you would get the number three-hundred and twenty-one! To make a this work you need an extra key that tells the calculator when you have finished entering each number. On most RPN calculators this is called the "Enter" key and fulfills a similar function to an equals key on a conventional calculator but in reverse. So the example would actually be input as:
3 enter 2 enter 1 + x
This gives the correct answer, 9. If you wanted to work out "1 + 2x3" you would input this as:
1 enter 2 enter 3 x + (answer: 7)
You need to think of entering numbers as being like putting plates into one of those spring loaded plate stacking trolleys you get in canteens. Every time you enter a number, it is pushed onto the stack. When you eventually start using arithmetic operators, numbers start "popping" off the stack as needed. You can also push more numbers onto the stack. At the end of the calculation you will have "used up" all the numbers and the stack will be empty.
A calculator using conventional logic will internally convert the expression to the RPN form above. This may be achieved by parsing the bracketed expression before carrying out the calculation. But more likely the calculator logic will be pushing numbers down onto the stack every time a pair of brackets is opened or is implied by the operator precedence. So in effect an RPN calculator is offloading this work to the calculator user, resulting in simpler logic design in the calculator. Nowadays the design issues of using conventional bracket notation in an electronic calculator are trivial, and yet users of RPN calculators rarely seem to want to move over to the more conventional algebraic logic. Although RPN seems strange to the uninitiated, people who overcome the initial hurdle find it a powerful and elegant tool which is ultimately easier to use. Luckily for RPN devotees, Hewlett-Packard continues to develop RPN calculators, such as the HP32 and some of the latest models have the capability of both RPN and algebraic logic. And of course Calc98 also supports RPN as a user configurable option.
Will this be supporting SVGA graphics now?
OMFG FIRST POST
Anyone who have ever used a few microcontrollers know that PIC Micro's reign supreme. Why, there have been several webservers built using tiny SM 8 pin chips!
Z8's are just a resharshed version of the X8 with onboard memory and a serial port. Their preformance sucks. 577.6 kHz in this day and age? C'mon.
To conclude:
Z8, x86, AVR, 8051 == crap
PIC == Good
PIC's are great!
PS: Michael "censorware.org" Sims, you should apoligise for mentioning Z8's. They are an embarrasment to us all.
In november 1995, the ETV - student association of EE, Delft University of Technology, The Netherlands - allready did a similar thing.
It's in Dutch, but there are some pictures.
-- Sig (appended to the end of comments you post, 120 chars)
At the 19th Chaos Communications Congress in Berlin/Germany developers showed their newest developments for the closed-down Blinkenlights-Project
Celebrating its 20th anniversary the Chaos Computer Club has made a special present to itself and the city of Berlin. From September 12th, 2001 to February 23rd, 2002, the famous "Haus des Lehrers" (house of the teacher) office building at Berlin Alexanderplatz has been enhanced to become world's biggest interactive computer display: Blinkenlights (a term defined by the Jargon File). The upper eight floors of the building were transformed in to a huge display by arranging 144 lamps behind the building's front windows. A computer controlled each of the lamps independently to produce a monochrome matrix of 18 times 8 pixels. During the night, a constantly growing number of animations could be seen. But there was an interactive component as well: you were able to play the old arcade classic Pong on the building using your mobile phone and you could place your own loveletters on the screen as well. Blinkenlights was up and running at until February 23rd, 2002, running 23 weeks and 5 days in total. During that period, we constantly improved its feature set. Even now, work on Blinkenlights is not completed. The software has been released as Free Software under GPL. Our documentation video shows all aspects of the project in 11 minutes. For the friends of Blinkenlights we have prepared a little trailer movie [QuickTime 5 Format, 3,2 MB] [MPEG-1 Format, 3 MB]. If you want the soundtrack of the trailer have a look here. Overview Using your mobile phone you could play Pong with Blinkenlights or your friend. The program Blinkenpaint enables you to create your own animations allowing you to take part in our contest. For the nerds there is a description of the Blinkenlights Movie format and a couple of nice tools to display and convert your animations. A look behind the scenes reveals some technical details of our system. A list of press reports about Blinkenlights und a couple of interesting links to other projects complete the overview. Get a regular update on what is going on with the project on our News page. WebCam Those who wanted to have a remote view on the building were able to have a look at the pictures of our webcam. The WebCam is no longer in operation. We are going to publish the WebCam picture archive here soon. The BerlinOnline WebCam looked at Blinkenlights as well, although it was a bit more distant than our cam. Maybe you find some nice pictures in their archive as well.
I confess, I don't know much about how this system works... but wouldn't this be a neat way to get your protest message across? I mean, say you oppose Nike's sweat shop labour practices. Go to Nike headquarters, covertly set up the system, program a message like, "Just Don't Do It" or whatever strikes your fancy, and time it to start in the middle of the night. I expect the first few incidences would get huge media exposure, and have the added benefit of being somewhat more acceptable to the general public - thus, getting your message across to more people. I know it'd certainly grab my attention... you can see only so many crowds with signs before you sort of ignore them.
Phase II: Implement Soft- and Hardware for a Hardware-Based Blinkenlights Player.
Phase III:
Phase IV: Profit.
I was in Berlin last February and I saw Blinkenlights on the evening of 12th at Alexanderplatz and it was so great to watch. Hopefully we'll see something like this again some time. I wasn't able to make it to the one in Paris, but I'm sure it was just as great to watch.
dacs
Blinken Lights on The Keep
the Hell moderators! with To
Every generation thinks that they invented they latest gizmo. The "Blinkenlights" referenced at http://www.jargonfile.com/jargon/html/entry/blinke nlights.html
as being from 1959 is actually a rehash of a sign for radio transmitters (das transmittenmachinen). I was working on my novice ticket when I first saw a very yellowed version taped to a radio transmitter in 1962 at my "Elmer's" house in Key West, FL. He had been a radio operator on merchant ships going back to spark gap days and had picked up the sign somewhere along the way. Everything old is new again.
All these applications with so much blinking lights might be bad for the eye.
It's a well known fact that blinking light sources with a blink frequency below 16 Hz can do much damage to the eye and the optic neural system. This is one reason why you should always play 3D games like Quake on fast computers - if the fps rate is below 15 this effect might damage your eyes.
Despite all critics from well scientific authorties the members of the Blinkenlights Project have refused to increase the default blink frequency to 25 Hz. Only at this frequency damages can be really ruled out. The only reaction they got was: "Plz shut up, wnkr. Thx."
However, at this point I must warn you the set they blinking frequency at the blinking applications too high. At frequencies above 143 Hz the Starnikov-Holderman effect comes into play which has effects on the visual cortex, too.
Note also that this has nothing to do with refresh frequency of computer monitors - the refresh of a screen is not really a blinking effect, it's a gradual intensity/spectrum shift were very different formulas apply.
Owner of a Mensa membership card.
you chicks wanna cyber?
Where is your regular dumbass comment?
Everytime someone mentions Blinkenlights I think about StarWars.
(If it hangs then I can tell you it's a complete remake of StarWars episode IV)
Look a monkey!
The Z8 runs at 50MHz. It's widely used by companies like Ford and Boeing. PIC stopped being the best 5 years ago, and has since then been surpassed by Motorola and Zilog who offer cheaper and better products.
Regards,
Brett Glass <brett@lariat.org>
Patent violation programming contest II (remember first at 19C3 of CCC? http://www.ccc.de/congress/2002/).
- party/patente/i ndex.html
t .h tml
Some violating software pieces of Patent-PartyI
http://www.elug.de/projekte/patent
Patent violating prograsmming contest II
http://www.elug.de/projekte/patent-party/contes
Why didn't slashdot accept a story about 19C3? Europe's most important Hacker congress and shlashdot remains silent.
http://www.ccc.de/congress/2002/index.en.html
1. Install fancy blinking lights in a building
2. Controll these lights to show various animations, attracting people to stare at them
3. Show animated ads in size of a whole building with this technology
4. Profit!!
Now if I only knew what to put in step 3... uh wait a second...
U.S. Decision On Iraq - How Policy Was Set
By Glenn Kessler Washington Post Staff Writer (Sunday, January 12, 2003; Page A01)
On Sept. 17, 2001, six days after the attacks on the World Trade Center and the Pentagon, President Bush signed a 21/2-page document marked "TOP SECRET" that outlined the plan for going to war in Afghanistan as part of a global campaign against terrorism.
Almost as a footnote, the document also directed the Pentagon to begin planning military options for an invasion of Iraq, senior administration officials said.
The previously undisclosed Iraq directive is characteristic of an internal decision-making process that has been obscured from public view. Over the next nine months, the administration would make Iraq the central focus of its war on terrorism without producing a rich paper trail or record of key meetings and events leading to a formal decision to act against President Saddam Hussein, according to a review of administration decision-making based on interviews with more than 20 participants.
Instead, participants said, the decision to confront Hussein at this time emerged in an ad hoc fashion. Often, the process circumvented traditional policymaking channels as longtime advocates of ousting Hussein pushed Iraq to the top of the agenda by connecting their cause to the war on terrorism.
With the nation possibly on the brink of war, the result of this murky process continues to reverberate today: tepid support for military action at the State Department, muted concern in the military ranks of the Pentagon and general confusion among relatively senior officials -- and the public -- about how or even when the policy was decided.............
Read the full article here - How U.S. Policy On Iraq Was Set
In addition to others that did something similar, the BBL headoffice in Brussels, Belgium have even made a contest out of it in December '99. You could download a program and send in your own animations, see BBLMarnix2000. It was fun to see the animations when driving towards it. Some can still be viewed in the archive.
I don't have anything to say, I just feel sorry for this story since it only has 39 comments. This will push it up to 40, which maybe won't look quite so sad there on the front page.
I forgot to mention that there ARE hardware-project already available. But they all need to have a running PC. My "Phase II"-Hardware Player should be portable. Most likely it will also include the original PONG-Game so you can use it as some kind of portable BLINKENLIGHTS-Gameboy or so :-)
Look, this thing is totally safe! Built it myself, you know. You just press that button like this and then turn that lev
Or, if you want to attach the nodes to Ethernet, the Ubicom IP2022. It's still reasonably inexpensive, but has 64K of Flash, 20K of RAM, and built-in 10baseT Ethernet support. That way you don't have to invent any new protocols to wire the things up.
The only drawback of the IP2022 is that the SDK is somewhat expensive. If you just want basic tools (a compiler, assembler, linker, and debugger), you can use the GNU tools. But the SDK includes the Ethernet driver, TCP/IP stack, small HTTP server, etc., which would be useful for an application like this.
Disclaimer: I've worked for Ubicom for a little over four months. Before that, I was a satisfied customer, having designed their SX part into the first generation ReplayTV box to handle IR remote functions.
I love how they moved the page to Sourceforge due to heavy traffic from slashdot. Suck it, OSDN!
sulli
RTFJ.
...lights blinken you!
I was living in Berlin during the DDR collapse and the wall. Before that collapse, Technical Univ on West side had setup a lazer pointing to the east (or was it the other way around). I wonder of that was used for communication between the E and the west.
I can remember the day the checkpoints went open and ANYONE in the east can go to the west. Everyone on the E made a bee-line to the KuDam (Kufurstendam St) where all the big retail stores were.
Last summer, I go back there, and there is very little evidence of the WALL and it's really hard to tell whats E or W now.
Berlin is Awsome. Free wiFi on most of the parks (Complements of CCC).
To quote Ted Knight in Caddyshack
Don't you people have jobs?
Like the ads on the buildings in Bladerunner??
I mean why not? They hammer us everywhere else now, they even spam our cell phones and beepers with crappy ads for crappy products.
Might as well get the buildings going too!
I think the project they had was cool. It was a fun thing and it had major geek factor. But I think it was a prototype for things to come..
This drawback can be easily avoided, if you use ready-made module with high-level programming language.
Check for example IPJV-ES module - it is based on the IP2022 and have embedded Java virtual machine. All necessary external interfaces available, you simply need to write your Java program and upload it to the build-in FTP - and project like this is finished.