I just posted the project page for my
Cheap Generic LED Sequencer that I designed for Professor Conrad.

It is based on the ATTiny84 Chip. But I’m sure it would work with the ATTiny44 or ATTiny24.

The neat thing about this one is I have 8 pre-programmed sequences and they are selectable by jumpers or switches.

Not really a snow day but it was finally cold enough and the humidity was low enough in Spicewood, TX to make a little snow. We don’t have the snow makers like the ones on snowathome.com (Although I’m sure we will some day.) So we used a paint sprayer filled with water attached to an air compressor.

The temperature was about 29° and 51% humidity.

Since most of the projects I work on with Atmel are USB based the first thing I do is load AVRUSBBoot on a chip. Once the bootloader is on the chip you can re-program it by setting a jumper on your circuit and using the avrusbboot command line interface. (Example: avrusbboot ./filename.hex)

But how to get the bootloader on the chip in the first place? Easy. Buy a AVRISPMkII from an Atmel distributor. It comes with the necessary hardware and software to program chips. Then the question becomes: If I have a programmer why would I need a bootloader? I guess the answer is: convenience. Once a circuit is built with usb support, which is only 4 wires, it is easy enough to put a jumper on and use the bootloader. When I order a new batch of chips I could put them all on the programmer and load the bootloader all at once.

The downside to the usb bootloader is that it requires a 12Mhz crystal to be attached to the chip. (I primarily use Atmega8 chips.)

Although I have never used one there is a possibility of using a serial port or parallel port programmer built out of very few, cheap components.

There is a good overview of all the methods of programming an avr at ladyada.net.

One of the greatest beginning tutorials I have found for Atmel programming is the I Make Projects article called “A Quickstart Tutorial for ATMEL AVR Microcontrollers.” If you are just starting buy a couple Attiny45 chips and follow that.

Warning: To get a bootloader to work with usb you have to change fuse settings. It is easy to “brick” a chip if you give it the wrong fuse settings. Especially changing the clock and re-assigning the reset line. (Reset is needed to activate the In Circuit Programming.) Read, re-read, and triple read before reprogramming fuses. Look at RSTDISBL, SPIEN, and CKSEL.

When I prep an Atmega8 for use with the avrusbboot program I use Hight fuse @ C0 Low Fuse @ 9F and locks set to EF. As soon as you hit the button to program these fuses it will absoulutely need that 12Mhz crystal on pins 9 and 10 with the 27pf capacitors. Or you wont be able to talk to the chip again.

An online fuse calculator for avr chips.

Now that I have my quick protoboard together it allows me to take other people’s projects and put them together really quickly. Today I built the USB-LED-Fader. Since the hard parts were already done it took about 5 minutes to add the 4 resistors and LEDs to a breadboard. Then another 5 minutes to compile and upload the firmware using the bootloader.

Then I spent about an hour playing with the different LED patterns. This is a really fun project. I can see tons of potential for different status lights. Tie a cpu meter to one of the lights… the faster it flashes the more cpu is being used. One LED for email status. One for network traffic. And finally one for server status.

(The photo from the atmega8 development board shows this project on the breadboard.)

Last night I stared building a atmega8 development board. Tonight I finished it.

I got tired of building the same circuit over and over; so I made a generic board that I could slap onto a breadboard and quickly try out projects. It also allows me to rapidly prototype something new.

I based the board on AVRUSBBoot. The only thing I changed was the programming pin. I moved it to PD7. This allowed me to put PB* and PC* on the plug side of the board.

On the right hand side of the board I brought all the PortC and PortB pins as well as + and GND to a row of header pins.

The important thing about this board to me is that it is USB powered and based. I don’t need to hook up a programmer, I just use the bootloader and usb to update the software on the chip.

My header looks like this:

  1. PC5
  2. PC4
  3. PC3
  4. PC2
  5. PC1
  6. PC0
  7. GND
  8. PB0
  9. VCC
  10. PB5
  11. PB4
  12. PB3
  13. PB2
  14. PB1

Last night I showed my “Hallucination Generation” device at the The Robot Group meeting and many people asked me how the device could cause visual hallucinations. I have a theory about that.

First in normal people speak. Sensory overload in your eyes makes you see stuff.

Now in geek speak. The phenomenon of pareidolia, which is a type of apophenia, is the brain’s (dis)ability to see patterns where none exist. When the UBHG device flashes lights in the eyes it causes retinal fatigue. As the duration of exposure and frequency changes, the amount of noise coming from the cones and rods increases. The brain does its best to interpret the noise. Depending on the viewer’s natural tendency of pareidolia, what the brain interprets can range from just a flashing light to religious icons. Most see patterns like checkerboards, spirals, and triangles.

The next logical question is: Why use Alpha, Beta, Delta, and Theta waves as the basis for the frequency of flashing? I guess the best answer is: Why not? They seem to work fairly well. I do want to make a future version where each of the four frequencies can be tuned to what works best for my body’s specific nature.

Introducing the Unfocused Brain Hallucination Generation device. A Trance Machine based on visual stimulation.

In ancient times people used what is known as the Psychomantium to talk with the spirits. Nostradamus used one to tell the future. In the 1960′s Brian Gysin and Ian Sommerville created the Dreammachine. Recently pioneer Mitch Altman gave us the Brain Machine in Make: Volume 10.

All of these devices try to bring us to a heightened state of consciousness where we can achieve our full potential commune with the universe and see the future.

My device does one thing and one thing only. Makes you see trippy stuff.

I’ve built a Psychomantium. I built the Brain Machine. What I learned was that playing with your visual processing can make you see stuff.

The Brain Machine makes you see really neat stuff. Stuff like I used to see in the old days staring into a Circle K cup held over a strobe light. I tried the Brain Machine without the sound and it seemed to make me have hallucinations as well as with the sound. Plus certain transitions, like from theta to delta, made really neat visuals.

Getting bored quickly and wanting to just have the transition visual effects I made my own. This one has buttons. It allows you to switch from one state to another at will. It allowed me to find out what worked best for me.

This is just the start of my path down the visual stimulator trance machine path. I plan on making one that I can tune to which ever frequencies in each range work best for me. Then I plan on making one where I can easily store programs of different patterns and play them back. Possibly as a USB device. I have even thought about making one that will fill a whole room with light so that the patterns can be given to me while sleeping.

This is going to be fun. 8)

Like I said in my last post I have been working on some tools for writer brainstorming. The first one was the “article title writer” at TheWritersSecret.com. Next is a one for brainstorming movie titles. I call it “Movie Brain”.

The tech behind it:

It is written in JavaScript. That way the work of sorting through the data is done by the client machine instead of the server. JavaScript also has some pretty decent string handling abilities.

I collected over 11,000 titles from the WikiPedia list of movies. These are stored by category and are processed into usable data using a combination of awk, grep, and php scripting. For example:

cat horror_words.txt | awk '1==1 {printf("\"%s\",\n",tolower($2));}' | sort | uniq >movies_all.js

The engine uses a very simple template technique. Examples:
“() meets (2).” The parenthesis would be replaced by two different random words. “Boy meets Bacon.”
“The {} and the ()” The brackets would be replaced by a random amount of random words and the parenthesis would be replaced by a single word. “The egg substitute and the curmudgeon.”
“[]: {}” Here the [] means a year. “2012: Pirates Invade”

The last piece of tech was a fun part. When you generate the random list of movies you can see what they would look like with your standard coming soon movie title over a black screen. Just click on one and see what I mean. It uses JavaScript and CSS to generate and animated the title. For a time I had added zooming in on the title but I didn’t like how much processor it hogged.

I also used a technique for the coming soon generator, to keep it all client side, that I had never used before. A couple days ago a friend asked if it were possible to do forms without a server. Apparently it is possible if you are using method GET. You can just have JavaScript parse the URL to read the data.

While writing the JavaScript I found a wonderful resource JavaScript equivalents for PHP functions.

Tonight I am working on a brainstorming tool which needs lists of movie titles.

The tool will eventually be able to generate movie titles based on which genre you are interested in. I made one of these back in the ‘day’ when I was wanting to make a horror movie. The title I came up with then from the brainstorm software was ‘Reanimation Vermin’. Which was a story about a mad man who identified with squirrels.

The tool I am making today will cover more genres and I will add the ability for you to give it a title and it will use Bayseian classifiers to say which genre your movie title would most likely belong to.

The most important thing I’ve learned today is which genres are most popular based on the wikipedia lists of movies entries. (Example: War Films)

11085 total
1960 horror.txt
1731 comedy.txt
1242 western.txt
1095 drama.txt
1011 noir.txt
921 sci-fi.txt
760 war.txt
523 action.txt
499 fantasy.txt
488 sports.txt
452 adventure.txt
303 disaster.txt
100 comedy_scifi.txt
I imagined horror would be #1. I was surprised that western was greater than drama.

Last night I demoed the “Trampoline Sensor MK II” (patent pending) at the EFF Plutopia event @ SXSW.

If you were at the event and have any questions please leave feedback here.

Video by Vern Graner of the Sensor in action at a The Robot Group meeting.

The trampoline sensor was awarded an Editor’s Choice Ribbon at Maker Faire Austin. Local news Video of the Trampoline Sensor MK II @ Maker Faire. (About 1/2 way into the clip.)

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