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• installing avrdude
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  My avrdude program is not installing. Could u tell me what might be the problem?

  Posted by DaChosen on December 04, 2008 at 04:53:53 Pacific Time

• installing avrdude
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  Installing the programming software is different depending on your Operating Sytem. Which OS are you using? Complete (and excellent, easy to follow) instructions for installing are on the Ladyada website:
  http://www.ladyada.net/make/minipov3/software.html
  
  See if that helps.
  
  Mitch.
  

  Posted by maltman23 on December 04, 2008 at 12:47:56 Pacific Time

• programming the 20 MHz chip
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  Hi guys,
  
  I just build the SLM, its my first project in soldering. I bought the -20PU Atmel, of course the frequencies for the sound are not right (a buzzing sound). LEDs seem to be alright, I am not sure.
  But anyway - the sound. In the slm.c file there is a value of 9637 (e.g. beta waves) at the channel OCR1A at 8 MHz. I divided by 2.5 (=20 MHz) and used 3854 for one ear. Sounded good, could be 400 Hz.
  The other ear (OCR0A) has a value of 38... what the heck.. I dont really know how to change that... :-/ Anyone an idea?
  
  Thanks!

  Posted by ollifreund on November 28, 2008 at 10:55:21 Pacific Time

• programming the 20 MHz chip
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  unless you added a 20MHz oscillator and altered the fuse settings, it should not be necessary to fiddle with the timers.
  
  most likely what is going on is that you didn't change the fuses from the factory defaults. this will result in the chip running at 1MHz rather than 8MHz.
  
  try "make burn-fuse" to set the fuses, then load the unaltered slm firmware.

  Posted by foobert on November 30, 2008 at 09:27:58 Pacific Time

• programming the 20 MHz chip
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  Yeah, the 20MHz chip really means that the chip runs at various speeds up to 20MHz. But both the 20MHz chip and the 10MHz chip will run at 8MHz when used with the internal oscillator, if you tell it to do so.
  
  The main difference between the 10MHz chip and the 20MHz is that the minimum voltage for the 10MHz chip is lower, so the batteries will last longer. But with two AA batteries running the Brain Machine, they will last pleny long with your 20MHz chip.
  
  As foobert said, you will need to program the fuse bytes to tell the chip to run at 8MHz on the internal oscillator. And to do that you do as foobert said:
  make burn-fuse
  
  That should get you going at the right speed.
  
  You need to burn the fuse bytes since by default, the microcontroller runs at 1MHz on the internal oscillator, and changing the fuse bytes let's the chip know to run at 8MHz on the internal oscillator.
  
  Mitch.
  

  Posted by maltman23 on December 03, 2008 at 18:11:35 Pacific Time

• programming the 20 MHz chip
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  Okay, thanks guys, I needed to burn the
  fuses.
  Right now I'm trying to add several
  frequencies (1-15 Hz, in 1 Hz increments),
  but somehow it doesnt work. Can be
  pretty frustrating (this is my first
  electronic project).
  I used super-bright LEDs, the normal
  ones were not bright enough.
  Tried the default program 3 times, didnt
  notice anything. I am not experienced in
  meditation. I will try to get into an
  EEG laboratory next week and try the
  program twice. If I get it done, I'll
  post it here.
  Is there any place on the net to download
  alternate slm.c ?

  Posted by ollifreund on December 05, 2008 at 09:58:03 Pacific Time

• programming the 20 MHz chip
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  Okay, thanks guys, I needed to burn the
  fuses.
  Right now I'm trying to add several
  frequencies (1-15 Hz, in 1 Hz increments),
  but somehow it doesnt work. Can be
  pretty frustrating (this is my first
  electronic project).
  I used super-bright LEDs, the normal
  ones were not bright enough.
  Tried the default program 3 times, didnt
  notice anything. I am not experienced in
  meditation. I will try to get into an
  EEG laboratory next week and try the
  program twice. If I get it done, I'll
  post it here.
  Is there any place on the net to download
  alternate slm.c ?

  Posted by ollifreund on December 05, 2008 at 09:57:56 Pacific Time

• programming the 20 MHz chip
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  i built a slightly modified brain machine with the audio on the two middle outputs so they both could use timer1, then rewrote the firmware. beat frequencies of 2Hz to 16Hz are available in 1Hz increments. the firmware is designed for rgb leds, but connecting just the red will work fine. another advantage is that the brightness of the leds is controlled by the firmware. for more info, see http://forums.ladyada.net/viewtopic.php?f=25&t=6688
  
  

  Posted by foobert on December 06, 2008 at 05:17:57 Pacific Time

• programming the 20 MHz chip
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  Cool -- glad you got the Brain Machine going. :)
  
  So, now that you are trying to hack the original program by creating 1Hz increments, what, exactly, are you doing to try to make that happen, and what, exactly, does not work?
  
  Everyone has different sensitivities to light. Some find the LEDs provided to be too bright, but most like them with this brightness. If you use super bright LEDs, they may be too bright. If you find that your eyes are feeling like they are fluttering or tearing, then the LEDs are too bright. If the lights are not comfortable it will be difficult to relax into the lights, as well as the ensuing hallucinations. Are you seeing any patterns or colors?
  
  If you try out the Brain Machine with an EEG, please post your results here. It would be really cool to see if you can get some correlation between your brain waves and the Brain Machine's output.
  
  Mitch.
  

  Posted by maltman23 on December 05, 2008 at 10:23:01 Pacific Time

• programming using Mac OSX and serial-usb cable
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  Hi - Great machine! I'm trying to get mine programmed.
  
  I'm using a USB-serial cable, and going through mac osx. I've done everything instructed on the ladyada site for running on a mac, including installing xtools - and have managed to install the firmware and check the fuses, as described here http://ladyada.net/make/minipov3/software.html
  
  So now, I'm at a point in your instructions where I run 'make program-mypov' and 'make program-slm'
  
  In both situations I get a similar error, using program-mypov as an example:
  
  ----------------------------------------
  make program-mypov
  
  avrdude -p attiny2313 -P com1 -c dasa -U flash:w:mypov.hex
  com1: No such file or directory
  
  avrdude done. Thank you.
  
  make: *** [program-mypov] Error 1
  ----------------------------------------
  
  I'm assuming this doesn't indicate a successful program. Is there somewhere in the code that I can edit to tell it where the usb-serial is located? Something else?
  
  The only clue I can offer is when installing the firmware I was supposed to type into the terminal window: avrdude -p t2313 -c dasa -P /dev/cu.usbserial-FTCYG5C --- which didn't work until I changed the "cu.usbserial-FTCYG5C" bit to read "cu.PL2303-0000201D" which was the name of my serial port when I ran that "ls /dev/cu.*" command. Is this a clue to getting the program-slm and program-mypov commands to work? Also, what would correct code look like?
  
  Any help extremely appreciated. This is my first chip project and very unfamiliar with coding. Thanks in advance.

  Posted by m880 on October 29, 2008 at 09:09:53 Pacific Time

• programming using Mac OSX and serial-usb cable
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  Hey - Just as an update, or for others needing this - i got it to work. Or it's writing right now.
  
  What worked: Open the makefile with a text editor and change "AVRDUDE_PORT = com.1" to be "AVRDUDE_PORT = /dev/USBserialname"
  ... the "USBserialname" being the name given when you prompt ls /dev/cu.* in the mac install on this page http://www.ladyada.net/make/minipov3/software.html

  Posted by m880 on October 29, 2008 at 11:14:50 Pacific Time

• Brainwave machine with RGB leds
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  Posted by yavid on September 09, 2008 at 11:20:50 Pacific Time

• Brainwave machine with RGB leds
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  Hi yavid,
  
  I've experimented with different colors, and haven't found anything too cool to happen. But that's maybe just me. Eyelids do seem to filter for red light. But if you try out different colors and get some interesting results, please post about it.
  
  Cheers,
  Mitch.
  

  Posted by maltman23 on September 09, 2008 at 12:06:55 Pacific Time

• Brainwave machine with RGB leds
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  Sorry Mitch, my post seemed to have gotten cut off there. My idea is to make a brainwave machine with a dimmer and RGB LEDs. I'd mount the LED's behind light diffusing plastic. I am hoping that by doing this the user could use the machine with their eyes open and experience the colors.
  
  On the software side of things I'd like to see the color of the LED to slowly transition from one color to the next as the machine transitions from one frequency to the next. The colors would be paired to the brainwave you are trying to achieve (as an example I read in another Make article that blue is good for alpha).
  
  I think I have a good idea, trouble is I have no idea where/how to start. Can you point me in the right direction? Would I be able to accomplish this by adapting your schematic and firmware? I was also thinking maybe I could adapt a couple of BlinkM's to do this? I really don't know anything about electronics but I'd like to learn, just need some guidance.
  
  Thanks in advance.

  Posted by yavid on September 11, 2008 at 13:24:03 Pacific Time

• Brainwave machine with RGB leds
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  yavid,
  
  i finally got around to building a minipov rgb brain machine yesterday. only one bug in the tiny2313 version of the firmware. see this thread at lady ada's forums for a description. scroll down to the 9/23 entry for the minipov version.
  
  last night i had it flashing blue instead of red and rather than the usual geometric visuals i was seeing washes of color and at the end was seeing forest scenes.
  
  anyway, take a look. i think you'll like it.
  
  bobby

  Posted by foobert on September 24, 2008 at 07:39:24 Pacific Time

• Brainwave machine with RGB leds
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  Thanks Bobby. I noticed in the ladyada forum you say the led washes from green to blue while the red flashes? Is it possible to change the firmware to do what I'd like to attempt (colour slowly changing with the flashes).

  Posted by yavid on September 30, 2008 at 13:08:16 Pacific Time

• Brainwave machine with RGB leds
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  that should be possible. as mitch has pointed out red is the easiest color to see through closed eyelids. i've tried blinking blue, using a 3.3v supply with leds with a nominal vf of 3.4v on the blue and though i can see it, it's not nearly as bright as the red.
  
  the reason i did one color blinking while two fade continuously is that it was easy to code to test the hardware, but i really liked it and never procreeded to do anything further.
  
  the main trick to color fading is calculating a step size depending on starting and ending colors and the length of the fade. the numbers are usually pretty small, so integers don't really cut it.
  
  the trick will be to make sure you always have enough light so that the blinking will be visible.

  Posted by foobert on October 06, 2008 at 01:54:38 Pacific Time

• Brainwave machine with RGB leds
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  mitch,
  
  i built an rgb brain machine that flashes the red while fading the blue and thr green in and out. it seems to me that the visuals are considerably more colorful. i used a 3.3 volt boost supply so the blue and green are very bright.
  
  had one interesting experience. i was concentrating on my breathing as advised, but began to find breathing to be distracting and tried to stop. almost worked.
  
  if nothing else the fading blue and green leds make it more interesting to watch someone else using it.

  Posted by foobert on September 09, 2008 at 18:05:08 Pacific Time

• Brain Machine workshop in Washington, DC
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  If anyone happens to be in or around Washington, DC -- I'll be giving another Brain Machine making workshop at HacDC on Sunday, 6-September, at 2pm. The workshop is free, but I'm asking people to reimburse me $25 for the parts. You can successfully build and bring home your own Brain Machine! For directions and more details:
  Brain Machine Workshop
  
  Cheers,
  Mitch.
  

  Posted by maltman23 on September 06, 2008 at 11:20:36 Pacific Time

• sorry again
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  To the following;
  
  http://d.hatena.ne.jp/dissociation/20080831

  Posted by puppu on September 06, 2008 at 09:40:52 Pacific Time

• sorry again
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  Hi puppu,
  
  That's great that you got it going! The Brain Machine should work well with just the sound.
  
  Without the lights, however, you will be missing out on the beautiful hallucinatory colors and patterns that you get with them.
  
  Getting the lights going is a fairly simple task now that you have everything else working. Please let me know how that goes.
  
  Cheers,
  Mitch.
  

  Posted by maltman23 on September 06, 2008 at 10:48:41 Pacific Time

• sound only but
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  Hello
  
  very unconscious　awakening.
  
  i labored pretty to make. anyhow, i made. To the following;
  
  http://qrl.jp/?286103
  
  next time, i'm going to make LED parts.
  
  

  Posted by puppu on September 06, 2008 at 09:34:34 Pacific Time

• Problem with programming in the new firmware...
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  Okay so I finally got the whole VVVVVV thing to work, which was awesome. But now when I change the directory (cd c:/etc.) to where the SLMFirmware unzipped contents are, I can't do the "del slm.hex" thing. The slm file is saved as a .C file. And so if I do "del slm.c" it deletes it or whatever, but then when I "make slm.c" it says "make: *** No rule to make target 'slm.c'. Stop."
  And so now I'm trying to figure out if I need to change the slm.c file into a slm.hex file. I looked in the programming code and even replaced the slm.hex to slm.c to see if then cmd would recognize the slm.c file, but it doesn't. (I changed it back). Any help would be greatly appreciated. Thanks.

  Posted by David H 206 on August 21, 2008 at 19:58:58 Pacific Time

• Problem with programming in the new firmware...
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  Hi David,
  
  If you got the VVVV pattern, you are really there!
  
  Leave the "slm.c" file named "slm.c". Then type:
  make slm.hex
  Then connect your Brain Machine (with the power off) to the serial port, then turn on the power to the Brain Machine, then type:
  make program-slm
  
  You will then have a Brain Machine!
  
  Enjoy,
  Mitch.
  

  Posted by maltman23 on August 21, 2008 at 23:01:53 Pacific Time

• Problem with programming in the new firmware...
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  WOW! It worked, haha. Thanks so much.
  But just curious, why did I simply need to leave out the 'del slm.hex' step?
  (Might as well learn it while I can...)

  Posted by David H 206 on August 22, 2008 at 00:20:28 Pacific Time

• Problem with programming in the new firmware...
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  You actually didn't have to leave out that step. You just had to not care that the command window told you that it couldn't find "slm.hex". That step to delete the "slm.hex" file is there because the "makefile" won't create a new "slm.hex" file if there happens to be an old one present.
  
  Here's more details on this:
  The "slm.c" file is a text file, full of instructions that you want the Brain Machine's microcontroller to perform (this is the controlling software, known as firmware). But microcontrollers don't understand text, they understand machine code, and the "slm.hex" file is a representation of the machine code, converted from the text instructions in "slm.c" by the "makefile" (actually, the "makefile" invokes a bunch of software to do perform the necessary tasks), ready to be programmed into the microcontroller's memory. But if there is already a "slm.hex" file present, the "makefile" will keep the old "slm.hex" file (rather than create a new one), even if you change the "slm.c" text instructions. So, you need to delete the old one first.
  
  Happy hacking!
  Mitch.
  

  Posted by maltman23 on August 22, 2008 at 08:00:00 Pacific Time

• hey mitch,
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  this has been driving me nuts. which is usually a pretty short trip. it looks like your makefile is set up so that "make clean" deletes the source.
  otherwise, it's been a blast.
  bobby

  Posted by foobert on August 05, 2008 at 08:27:24 Pacific Time

• Can't make it work
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  Hi Mitch
  After building the kit the LED's (4) all light and are blinking at various speeds.
  All software was downloaded and unzipped but that's as far as I can get it to work.From cmd.exe i get a message saying that "make is not recognized as an internal or external command, operable program or batch file" and nothing happens.
  I have also noticed that all the files now seem to be saved as wordpad docs in machine code or something.
  Hope you can throw some light on the subject.
  no Pun intended
  Tom

  Posted by speedwayrider on August 03, 2008 at 11:02:38 Pacific Time

• Can't make it work
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  Hi bobby,
  
  Sorry about that. I just left "clean" the same as from the MiniPOV3 firmware. I guess I should try these things before publishing them (embarrassment).
  
  And it also just goes to show that you should always have backups of all you files.
  
  I hope it's a short trip back to a fun life for you of making cool things.
  
  Mitch.
  

  Posted by maltman23 on August 05, 2008 at 10:03:50 Pacific Time

• Can't make it work
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  Hi Tom,
  
  If the lights are blinking as you described, then you have probably built everything correctly. Yay!
  
  It sounds like the software isn't installed properly. Sounds like you're using Windows. (Windows is actually the easiest for programming hardware.) Windows needs WinAVR. The complete, step-by-step instructions (very easy to follow) are on the Ladyada website:
  http://ladyada.net/make/minipov3/software.html
  
  You said that you unzipped the downloaded file. Did you double-click the setup file to install the software? Anyway, try following the instructions from the above link, and let me know if that helps.
  
  Best,
  Mitch.
  

  Posted by maltman23 on August 04, 2008 at 11:44:08 Pacific Time

• Can't make it work
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  Hi Mitch
  I followed the instructions from the website and the software seems to be functional, however it still did not do what it is supposed to do, I got this error message.
  Microsoft Windows [Version 6.0.6001]
  Copyright (c) 2006 Microsoft Corporation. All rights reserved.
  
  C:\Users\Tomm>cd c:\
  
  c:\>cd minipov3
  
  c:\Minipov3>dir
  Volume in drive C is S3A6022D501
  Volume Serial Number is EE5D-DA63
  
  Directory of c:\Minipov3
  
  04/08/2008 07:22 PM <DIR> .
  04/08/2008 07:22 PM <DIR> ..
  05/05/2005 08:01 PM 289 all_leds.c
  27/05/2007 02:13 AM 316 all_leds.hex
  08/04/2007 03:33 PM 612 alt_leds.c
  27/05/2007 02:13 AM 488 alt_leds.hex
  27/05/2007 01:57 AM 2,760 digg.c
  27/05/2007 02:14 AM 832 digg.hex
  27/05/2007 02:13 AM 3,107 eyebeam.c
  27/05/2007 02:14 AM 906 eyebeam.hex
  27/05/2007 02:04 AM 2,999 largeimage.c
  27/05/2007 02:13 AM 902 largeimage.hex
  27/05/2007 02:05 AM 3,165 make.c
  27/05/2007 02:14 AM 914 make.hex
  27/05/2007 02:06 AM 3,468 makefair.c
  27/05/2007 02:13 AM 963 makefair.hex
  17/04/2008 06:29 PM 5,121 Makefile
  27/05/2007 02:14 AM 3,164 makezine.c
  27/05/2007 02:14 AM 914 makezine.hex
  27/05/2007 02:12 AM 2,664 minipov.c
  27/05/2007 02:13 AM 971 minipov.hex
  27/05/2007 02:12 AM 2,217 mypov.c
  27/05/2007 02:13 AM 820 mypov.hex
  05/05/2005 02:09 PM 813 test_leds.c
  27/05/2007 02:13 AM 754 test_leds.hex
  05/05/2005 08:10 PM 470 test_sensor.c
  27/05/2006 08:19 PM 1,444 test_serial.c
  25 File(s) 41,073 bytes
  2 Dir(s) 19,629,367,296 bytes free
  
  c:\Minipov3>make program-minipov
  avrdude -p attiny2313 -P com4 -c dasa -U flash:w:minipov.hex
  process_begin: CreateProcess(NULL, avrdude -p attiny2313 -P com4 -c dasa -U flas
  h:w:minipov.hex, ...) failed.
  make (e=2): The system cannot find the file specified.
  make: *** [program-minipov] Error 2
  
  c:\Minipov3>
  Also at some point do I follow the instructions that came with the kit,
  they seem to indicate something different
  Tom

  Posted by speedwayrider on August 04, 2008 at 16:52:18 Pacific Time

• Can't make it work
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  Hi Tom,
  
  It looks like you have the software installed OK now.
  
  It also looks like you changed the line in the "Makefile" file to:
  AVRDUDE_PORT = com4
  Are you sure that your serial port is on com4? If the serial port is a different port than the one specified in the "Makefile" file, then you would get the error message you got.
  
  You can see what your serial port number is by going to the "Device Manager":
  Start -> Control Panel
  double-click on System
  choose the Hardware tab and click on the Device Manager button
  
  If you have a serial port on your computer, then double-click on the Ports icon. If you have a USB-to-Serial converter, or some other kind of converter to put a serial port on your computer, then it may be listed somewhere else in the Device Manager list.
  
  Not all USB-to-Serial converters work with the AVR chips. Be sure to get one that is recommended on the Ladyada website:
  http://ladyada.net/make/minipov3/software.html
  
  Please let me know if that helps, or if you have any further questions or problems.
  
  Once you can program the microcontroller you continue to follow the instructions in the MAKE Magazine article, which hacks your MiniPOV into a Brain Machine.
  
  Mitch.
  

  Posted by maltman23 on August 04, 2008 at 18:11:02 Pacific Time

• Can't make it work
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  Hi mitch
  Yes! I am using a USB to Serial port cable
  ( neXXtec part# 2608042 from The Source )
  It does use Com port 4, as/device manager
  so it looks like this one does not work.
  Have to go searching again.
  Thanks Mitch.
  Tom

  Posted by speedwayrider on August 05, 2008 at 06:27:32 Pacific Time

• Can't make it work
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  Hi Tom,
  
  You are really close to being able to program. Bummer that your USB-to-Serial converter is one of the ones that doesn't work with the AVR microcontrollers we're using. Ladyada suggests converters that are known to work near the top of this webpage on her site:
  http://ladyada.net/make/minipov3/software.html
  
  Please let me know what happens.
  
  Best,
  Mitch.
  

  Posted by maltman23 on August 05, 2008 at 07:55:09 Pacific Time

• fuses verification error
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  Hi,
  I picked up a kit at Hope. Everything seemed fine, the
  'VVVV' test went perfectly. Then I downloaded the slm
  firmware, compiled it and typed 'make program-slm'
  
  this is what I got:
  
  avrdude: verifying ...
  avrdude: verification error, first mismatch at byte 0x0000
  0x80 != 0x00
  avrdude: verification error; content mismatch
  
  avrdude: safemode: lfuse changed! Was e4, and is now 0
  Would you like this fuse to be changed back? [y/n] n
  avrdude: safemode: hfuse changed! Was df, and is now 0
  Would you like this fuse to be changed back? [y/n] n
  avrdude: safemode: efuse changed! Was ff, and is now 0
  Would you like this fuse to be changed back? [y/n] n
  avrdude: safemode: Fuses OK
  
  avrdude done. Thank you.
  
  make: *** [program-slm] Error 1
  
  
  What do I do now? I've tried re-running it several times, no-joy - and I can't reburn the minipov firmware either.
  
  any help would be appreciated.
  
  thanks,
  -sandy

  Posted by saender on July 26, 2008 at 22:35:08 Pacific Time

• fuses verification error
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  Hi sandy,
  
  If you were able to program in the VVVVV pattern, then that's a great start. It means that everything worked at the time you did that programming.
  
  My guess is that there is a solder connection (or two or three) that are intermittent. Try going over all of your solder connections again. With a clean solder iron tip, touch the tip to each pad, and let the solder melt and flow on each pad for about 1 second each. Another thing to look for is that there is a mound of solder at each pad (not flat, level with the board). If there are any pads without a small mound, then add a little more solder.
  
  There are 3 qualities to a good solder connection:
  1) the solder flowed nicely all around the lead and the pad (smooth all the way around the pad, with no lumps)
  2) the solder is somewhat shiny (not pitty looking)
  3) each pad has a small mound of solder (not flat against the board).
  
  Also, make sure that the power from the two battery leads is still making a good connection, and that the power is on when you program.
  
  See if that gets you going again.
  
  Best,
  Mitch.
  

  Posted by maltman23 on July 26, 2008 at 22:58:46 Pacific Time

• More results?
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  i'm interested in hearing about people's experiences with this gear. This project was my first (but definitely not last!) soldering attempt. The brain machine is very cool. I've had a lot of very positive feedback from users, with a couple being kinda tweaked out and ending the sequence early.
  Is it possible that this device just isnt for everyone? I make it a point to ask people if they're prone to seizures or have been diagnosed with ADHD. I feel almost like a doctor when setting them up.
  One issue I need to tweak is ambient sound. Folks are often distracted by the sound of events around them. How can I evade this/ I used a pair of ham radio headsets (because they look so dang cool), putting dollar store guts into them...
  Thanks, Mitch, for putting this out there. One guy told me that he can't imagine why people would want to shoot up or snort stuff if they had this machine. The same guy said, "You're changing the world 14 minutes at a time!"

  Posted by WantonInn on July 22, 2008 at 15:47:25 Pacific Time

• More results?
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  Hi WantonInn,
  
  I'm very glad you like your Brain Machine, and are happy soldering and making things. :) Please make more cool things!
  
  The Brain Machine isn't for everyone. Like you, I always warn people before they try it: blinking lights and epileptic people shouldn't mix -- most epileptic people agree! I've been in the presence of thousands of people using Brain Machines. I've found that about 90% really love it. About 5% really hate it. And the other 5% like it OK if they slide the glasses down their nose so that the lights are not as bright on their eyes.
  
  I always ask people if the light is too intense, or if it feels too intense, and suggest that they can slide the glasses down their nose at any time if it's ever feeling too intense for them. This increases the number of people who like it.
  
  Best,
  Mitch.
  

  Posted by maltman23 on July 26, 2008 at 22:51:19 Pacific Time

• More results?
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  I'm afraid the design I 'm using doesn't allow for sliding the glasses down---we used welding goggles. I thought it would look cooler and block out more light (which they do). We put the led's on the inner lens' rather than the flip-up. Comfort is an issue for some people, I'm considering adding foam around the edges. And I want to figure out a way to encase the guts.
  I think I saw a thread down here somewhere about a coin cell battery/ Anyone had success with that? I haven't done a lot of research yet, but it would definitely mske the unit more compact. I guess I'd need to figure out what houses the cell, as well as the On/Off switch.
  Thanks again for sharing information. this meme lives...
  

  Posted by WantonInn on July 31, 2008 at 15:54:06 Pacific Time

• More results?
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  Hi WantonInn,
  
  Your goggle design sounds really interesting. Care to post a link to any photos?
  
  CR2032 coin-cell batteries work great to power the whole thing. They won't last as long as two AA batteries (which last many months of heavy use), but they are very light and small, and they last for about 200 complete sessions.
  
  I've used this battery holder for the coin-cell, from Mouser (35 cents for one):
  http://www.mouser.com/Search/Refine.aspx?Ntt=122-2420-GR
  
  You can use any cheap, small switch for an on/off switch.
  
  Best,
  Mitch.
  

  Posted by maltman23 on August 04, 2008 at 11:39:15 Pacific Time

• More results?
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  I just uploaded the only decent pic I have of it:
  http://www.flickr.com/photos/22512026@N00/?saved=1
  
  The board and batteries were affixed with double-sided duct tape. It started losing tackiness so now I've got it rigged with regular duct tape. It's a mess. I really need to house that stuff.
  I've been experimenting for years with lucid dreaming and 'psychic phenomena'. One problem I have is that, when I realize I'm dreaming, I start screwing around with flying and walking thru walls and whatnot. I want to see if I can bring back information from that state, which is why this machine caught my attention. so far, I'm just getting used to navigating that state, but am hoping my hunches will be fruitious...
  

  Posted by WantonInn on August 08, 2008 at 15:55:53 Pacific Time

• More results?
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  Hi WantonInn,
  
  Thanks for the photo. Steam Punk -- looks great!
  
  Duct tape is a great thing. For this case, however, the other great thing is even better: hot glue. Hot glue is your friend. Try it out. But neither are good for connecting to batteries. This is what battery holders are for. :)
  
  If you end up taking your glasses apart to put them back together in a nicer form, you can take the opportunity to increase the resistance of R7 and R8 -- this will decrease the brightness of the LEDs. Try a few values to see what you like best -- I'd try 470 ohms as a first try. If the lights are too dim at 470 ohms, try 330 ohms; if the lights are still bright, try 560 ohms.
  
  All the best with your experiments. If you find something interesting, please post -- I'm sure others will also be interested.
  
  All the best,
  Mitch.
  

  Posted by maltman23 on August 08, 2008 at 16:39:33 Pacific Time

• More results?
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  I dont think most people are having difficulty with the brightness, just being distracted by external sounds.
  I'm thinking of adding some sort of volume control so that ear buds can be used. As it is, ear buds make it too loud. I think I saw on here somewhere about adding a potentiometer (?).
  I also had a very farout idea of building one into a Victorian-style chair. It would have like a crank to lower the headset and knife-switch for power. I'd have to learn about upholstery, but it might be worth it...
  

  Posted by WantonInn on August 09, 2008 at 08:37:25 Pacific Time

• More results?
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  Making a Victorian electric chair is too wonderful! Please post photos if you do this!
  
  Adding a potentiometer is very easy. You can use a single stereo pot, or two individual ones (either way, use audio-taper pots). Or, you can just put in two larger resistors for R5 and R6, and do trial and error to find a good volume for you earbuds. But headphones work better. If you want the steampunk look, find some clamp-like headphones and spray them silver or gold, with a few industrial-looking parts glued on? Or, for your Victorian chair, you can mount small speaker in the helmet?
  
  Keep up the great thinking.
  
  Cheers,
  Mitch.
  

  Posted by maltman23 on August 09, 2008 at 10:33:33 Pacific Time

• Possible new project?
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  First off, I would like to say that this is an amazing project and introduction into the world of microcontrollers. What if we could do the same project, but as an intro to signal processing?
  
  I am in the middle of this kit, and something occurs to me. Correct me if I'm wrong, but the brain machine needs only to A. Remember 2 frequencies: one for the left ear and eye, and one for the right ear and eye, and B. Express each of those frequencies as both a sine wave of an appropriate amplitude for headphones, and a square wave of an appropriate amplitude for LEDs.
  
  My proposed idea is to satisfy A. and the first part of B. in a very simple way: simply create and play the frequencies through an MP3 player that supports stereo output, such as an iPod, computer, or $10 no-frills device. This device already outputs the desired frequency audio, and the only trick is to have it output the desired LED signal.
  
  But wait! Aren't the 2 LEDs going at the same frequency as the 2 audio channels? If that's the case, can't we build a circuit that takes the audio signal, converts the sine wave into a square wave with appropriate amplitude, and outputs both the original sine wave (amplified if necessary) and the LED driving square wave?
  
  This device would be easy to program with multiple tracks that could be chosen on the fly, it would be completely platform-independent (Macs would load the same audio files as any other OS users), and it would be a completely different lesson for the same device!
  
  I am in no way an electrical engineer, so I ask those of you in the know if this is actually feasible. I have taken enough courses to believe that it should be, and it could be just as fun as the original! Let me know what you think!

  Posted by AdamTheMechE on July 01, 2008 at 18:51:42 Pacific Time

• Possible new project?
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  Hi AdamTheMechE,
  
  I'm glad you like the project.
  
  There are ways of making an audio player become a Brain Machine. But it's a little trickier than you suggest. This is because the audio and the blinking LEDs work differently.
  
  The two LEDs blink directly at brainwave frequencies (in the case of this simple Brain Machine, they blink at one of four frequencies, one for Beta, one for Alpha, one for Theta). For instance, for Beta, the LEDs on each eye blink at 14.4Hz
  
  The two speakers, however, create the brainwave frequencies via binaural beats, which means that the brainwave frequency is the result of the difference between the slightly different frequencies in each ear. For instance, to create Beta waves, one ear gets 415.0Hz, and the other ear gets 400.6Hz, the difference being 14.4Hz, which is the low end of Beta.
  
  Using audio editing software, it is very easy to create an mp3 file that generates a 400.6Hz sinewave on one channel, and then goes through a sequence of offset frequencies in the other ear -- this could create the exact same sequence as the Brain Machine.
  
  Making an mp3 player do the blinking LEDS is not as easy. There are two reasons: 1) we need a third audio channel for the LED information; 2) mp3 players only play in the audio range, and brainwave frequencies are below this range -- so we would need a way to convert higher frequencies into lower ones. There are ways to do this -- such as a divide-by-256 counter, and then use a square-wave at 256 times the desired frequency. And, probably the easiest way to create the third channel is to use two mp3 players, and just start them at the same time (It is probably better, but it probably isn't way important that the LED blinking and the audio be exactly in synch.)
  
  If you play with this, or other ideas like this, please post to the blog again and give your results.
  
  Cheers,
  Mitch.
  

  Posted by maltman23 on July 02, 2008 at 15:16:01 Pacific Time

• Possible new project?
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  Hi Mitch!
  
  Thanks for the prompt response. As I said, I'm no electrical engineer, so I don't have the faculty to design such circuits on my own.
  
  Has the "binaural" method been tested on the eyes? I assumed playing a different frequency in each eye would induce brain waves in the same way as in the ears. If this is not so, then I understand the limitations of my idea. Again, great project! I hope to update soon with pictures of my soft sleep mask results!

  Posted by AdamTheMechE on July 02, 2008 at 16:30:30 Pacific Time

• Possible new project?
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  Hi AdamTheMechE,
  
  As far as I know, no one has done any research on whether the binaural effect would work with vision. Although somewhat surprising, it somewhat makes sense that binaural beats would work with auditory input, since beat frequencies are a physical auditory phenomenon. The somewhat surprising aspect of binaural beats is that there is nothing physically happening to cause the beat frequencies -- it is only perceptual. People are very good at perceiving differences in pitch of sound, and that is presumably the part of the brain that is being used to perceive binaural beats. The analog with eyesite would be perceiving different colors (i.e., different frequencies of light). But I wonder what would happen if we gave each eye a slightly different blink rate? Worth a try! If you try it out, please let me know what you find out.
  
  Best,
  Mitch.
  

  Posted by maltman23 on July 03, 2008 at 15:19:47 Pacific Time

• my kit assembled
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  finally got my kit I bought at SF Makersfaire 2008 put together.
  
  Thanks so much Mitch. I'll have to play with it more but i think the lights are a little too bright for me right now. Will try with wearing the glasses in different positions.
  
  Also you were right about the cheapie headphones being preferable. I tried the brain machine with my Etymotics ER4Ps and it was unpleasant both in volume and tone.
  
  Although now that I am reading this page again I see I used the old 400hz firmware.
  
  My build:
  http://flickr.com/photos/rkt88edmo/sets/72157605240499308/

  Posted by rkt88edmo on July 01, 2008 at 00:39:45 Pacific Time

• my kit assembled
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  Hey rkt88edmo,
  
  Glad you got yours going! And thanks for the photos. Looks cool in the Altoids tin.
  
  If the lights are too bright you have a few options: slide the glasses down your nose so the LEDs aren't shining right at your eyes behind your eyelids, or change R7 and R8 to higher values (try 270 ohms and see how they feel), or get a cheap headphone with a volume control.
  
  Using 200Hz instead of 400Hz isn't important, but most people like 200Hz better.
  
  Cheers,
  Mitch.
  

  Posted by maltman23 on July 01, 2008 at 01:08:50 Pacific Time

• Brain Machine Kits
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  Thanks for all your patience, we now have the Make version of the Brain Machine available online at the Maker Shed: http://www.makezine.com/go/brainmachine
  
  Thanks again to Mitch!

  Posted by LJPRO on June 30, 2008 at 18:15:09 Pacific Time

• my attempt
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  hello,
  you can see my version of the machine here. made utilizing a stripboard.
  
  i've used a few times and i found the visuals very nice, but didnt make me relaxed.
  
  ive tried different LED colors:
  - clear red LEDs - clear and bright concentric red ripple-like patterns
  - diffused orange LEDs - as above, but the shapes were softer
  - clear yellowish green - barely visible patterns
  - diffused blue - LEDs didnt even blink,- probably voltage was too low to run them
  
  cheers

  Posted by happybara on June 07, 2008 at 11:41:29 Pacific Time

• my attempt
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  Hi happybara,
  
  Thanks for posting your version of the Brain Machine.
  
  I've also had the best visuals with Red LEDs. I think this is because our eyelids filter for red.
  
  If you want to use Blue LEDs, you will need to use a 4.5v power supply (three AA or AAA batteries) instead of 3v, since, as you pointed out, Blue LEDs need more voltage to make them work (often 3.6v).
  
  If the Brain Machine got you seeing nice visuals, but didn't make you relaxed, then I'd guess that the LEDs were too bright for your eyes. Try sliding the glasses down your nose while using them -- the further down your nose, the less intense the light. There should be a range of positions where you see nice visuals, and where the light isn't uncomfortable for you. With nice visuals and no discomfort, you should feel very nicely relaxed about half way through the sequence (about 5 or 6 minutes).
  
  Cheers,
  Mitch.
  

  Posted by maltman23 on June 09, 2008 at 01:14:20 Pacific Time

• Question about kit
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  I was one of the lucky ones to get the kit at the maker faire, and I'm just getting around to putting it together now. I noticed that the kit includes two 2.2Kohm resistors (for R5 and R6) instead of 1Kohm. I imagine this won't be a problem, it will just make the audio quieter, but was this intentional?
  
  Also, I'm modifying this in a couple of ways. Instead of the glasses I'm using a comfy padded eye mask with built in headphones, designed for business travelers. I will also change the firmware so it goes down to delta waves and then stops without coming back up. I am hoping this will thus function as a sleep aid.

  Posted by erics1 on May 28, 2008 at 16:03:40 Pacific Time

• Question about kit
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  Hi erics1,
  
  The 2.2k ohm resistors are intentional. The original firmware (from the above link) uses 400Hz for the audio. Since that was a bit too much like buzzing mosquitos, I changed it to 200Hz, and 2.2k ohm resistors work better with this lower frequency. The latest firmware is available from my website:
  http://www.CornfieldElectronics.com
  click on the "maker faire" button, and then click on "the latest SLM firmware".
  
  Modifying it to go down to to Theta, with occasional pulses of Delta would be great for helping you sleep. Putting it in a comfortable sleep mask is also a great idea. This is what I'm doing (along with using a more complex model of brain waves) in the sleep mask I've been working on.
  
  Please post the results after you try things out.
  
  Cheers,
  Mitch.
  

  Posted by maltman23 on May 28, 2008 at 16:54:18 Pacific Time

• Question about kit
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  Thanks for the fast reply, and it's cool to know you are also working on a sleep version!
  
  I'll be happy to post the results when I have them. One more modification I'm attempting to make these more sleep-friendly: I'm putting the battery pack and controller into a teddy bear, with a long umbilical to the sleep mask.

  Posted by erics1 on May 28, 2008 at 17:09:03 Pacific Time

• USB Version
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  I've built my first brainwave machine and have been very happy with the results. My only complaint is that I don't like the serial interface on the minipov (my serial port is in the back of my computer and is not nearly as handy as the USB port in front). I'd like to build another brainwave machine with the following changes:
  
  -USB instead of serial
  
  -Volume Control and fader (I am nearly deaf in one ear so I'd like the ability to make that ear louder)
  
  -make use of the extra outputs by adding different colored LED's (prob red, yellow and blue)
  
  -use a 9V battery instead of the AA's.
  
  Now here's the problem: I've only just started getting interested in electronics and I am not sure how to accomplish all this (although the forums at ladyada have discussed the USB problem so I have some idea what to do there). I'm not asking anyone to figure all this out for me but I thought many people have probably already suggested or tried these changes and could offer some advice/help.
  
  Thanks Mitch for the great project. How's the more advanced design coming?

  Posted by yavid on May 27, 2008 at 10:22:14 Pacific Time

• USB Version
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  Hi yavid,
  
  If you would like to use USB instead of a serial port, you can buy a USB to serial converter for about $15. Though programming is much quicker directly through a serial port. Alternatively, to add USB support to the MiniPOV kit is possible, but not a beginner's project.
  
  Adding a volume control is pretty easy. Just add two potentiometers. Search through this blog (you might have to search through both pages) for "volume".
  
  Using a 9v battery isn't a good idea. You can do it, but you'll need a DC-to-DC converter or a voltage regulator. If you want smaller batteries, try a CR2032 coin cell.
  
  Using different colored LEDs may be fun to play with.
  
  I've been working on a bunch of projects, including TV-B-Gone Pro, as well as making the Brain Machine into a ready-made manufactured product that people can buy (I'm calling them Trip Glasses). Doing Maker Faires and other geeky conferences has also taken lots of time and energy (but way worth it!). These and other projects have slowed down my progress with the advanced version of the Brain Machine that will help people sleep. But I hope to have a version of it ready this summer.
  
  Best of luck with everything! Please post back to this blog with any results.
  
  Mitch.
  

  Posted by maltman23 on May 28, 2008 at 17:02:42 Pacific Time

• KITS!!!??!??!?
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  so ive been looking all over and i read on an earlier post that these kits may be available soon on the maker store but in all actuality im tired of waiting!!!! is there anywhere or any way i can buy a kit?

  Posted by Rody21 on May 20, 2008 at 20:58:12 Pacific Time

• KITS!!!??!??!?
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  Brain Machine kits sure have been popular. All 120 of the ones that were available at the Maker Faire sold out.
  
  Rob, the guy who runs the Maker Store, emailed me yesterday saying that he is in the process of putting together more Brain Machine kits so that people can get them from the online store. Hopefully they will be ready within a few days, so please check back soon.
  
  Mitch.
  

  Posted by maltman23 on May 22, 2008 at 00:28:48 Pacific Time

• KITS!!!??!??!?
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  Hi Mitch
  I have been reading a lot about Brain Wave generators and ended up on this forum. The Brain Machine project seems very fascinating and I am very keen on trying this out. I am however located in Mauritius Island (Indian Ocean) and I am not too sure how I could get my hands on one of these. Would appreciate any help please........
  Thanks
  Ashraf

  Posted by Ashraf_Esmael on May 25, 2008 at 04:39:55 Pacific Time

• KITS!!!??!??!?
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  Hi Ashraf,
  
  If you want to build a Brain Machine, all of the parts are available on the web, and they will ship anywhere in the world.
  
  You can download the article here:
  http://www.CornfieldElectronics.com/
  Click on the "maker faire" button, and then click on the link for "Make a Brain Machine". (There's other fun projects there that you can hack from a MiniPOV3 kit, too.)
  
  The article shows all of the parts you need and where to buy them on the web.
  
  If you want to wait until they become available at the Maker Store, you can buy a kit for the Brain Machine all in one box, from makezine.com
  
  Of course, when you build it, you can ask any questions you may have on this blog, and I'll answer them.
  
  Cheers,
  Mitch.
  

  Posted by maltman23 on May 25, 2008 at 10:47:35 Pacific Time

• Brain Machine Kit
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  Hi Mitch
  I picked up a Brain Machine Kit at the Maker Faire. My wife and I just love the Brain Machine! I programmed a sleep mode and we use it daily to fall asleep.
  I wanted to purchase the kit as gifts. Do you know where I can purchase them online? I didn't see them in the Maker Shed. Sure, I know I could piece a kit together but the kit sold at the Maker Faire was well packaged. The kit included everything (although I did run out of wire) and at a great price.
  Anyways, hope you know something about these kits.
  Thanks.
  -garagemonkeysan
  

  Posted by garagemonkeysan on May 17, 2008 at 08:58:46 Pacific Time

• Brain Machine Kit
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  Hi garagemonkeysan,
  
  I'm glad you're enjoying your Brain Machine. Would you be into posting the firmware you used to help you and your wife sleep? I'm sure there are others who would be into benefiting from that.
  
  Lots of people have been asking me if they could buy a Brain Machine kit. Up till now they've only been available at Maker Faires and at workshops I've been giving at hacker conferences and for other groups (for the same price as it would cost if you bought all the parts on your own).
  
  But I just asked the Make Magazine people if they would be into having them at their online Maker Store. I'll let you know what I find out.
  
  Mitch.
  

  Posted by maltman23 on May 17, 2008 at 09:45:55 Pacific Time

• Brain Machine Kit
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  Hi Mitch -
  
  Thanks for the quick reply.
  As recommended in the other post, I roughly cut your meditation sequence in half.
  
  //sleep sequence
  { 'b', 600000 },
  { 'a', 100000 },
  { 'b', 200000 },
  { 'a', 150000 },
  { 'b', 150000 },
  { 'a', 200000 },
  { 'b', 100000 },
  { 'a', 300000 },
  { 'b', 50000 },
  { 'a', 600000 },
  { 't', 100000 },
  { 'a', 300000 },
  { 't', 200000 },
  { 'a', 300000 },
  { 't', 300000 },
  { 'a', 150000 },
  { 't', 600000 },
  { 'a', 150000 },
  { 'a', 150000 },
  { 't', 600000 },
  { 'd', 30000 },
  { 't', 300000 },
  { 'd', 100000 },
  { 't', 200000 },
  { 'd', 200000 },
  { 't', 300000 },
  { 'd', 300000 },
  { 't', 200000 },
  { 'a', 10000 },
  { 't', 200000 },
  { 'd', 100000 },
  { 't', 500000 },
  { 'd', 200000 },
  { 't', 600000 },
  { 'd', 800000 },
  { '0', 0 } //last element to stop main_loop
  }; //end of table
  
  We usually drift off to sleep before the sequence ends. It's a little abrupt at the end because the light and sound instantly stop. But that's okay, it's a signal to remove the unit and place it aside. The current construction isn't exactly bed-friendly. I'm thinking about building a Brain Machine utilizing a sleep mask, surface mount LEDs and a long single cable that runs to a box that contains the MiniPOV and batteries.
  
  So hopefully, the Maker Store/Shed will begin stocking the Brain Machine Kits.
  
  For those not familiar with the Brain Machine Kit, it comes with all the parts: safety glasses, 30awg wire, resistors, MiniPOV kit, caps, headphones, instructions and even the crazy artwork. I had a blast building it!
  
  - garagemonkeysan
  

  Posted by garagemonkeysan on May 17, 2008 at 11:20:00 Pacific Time

• Brain Machine Kit
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  Thanks for posting your sequence. Taking out the short amount of Beta after Theta starts was a good idea.
  
  I like your idea of making a sleep mask. Please be careful with wires while you're asleep, since if you roll over you want to ensure that it won't limit the amount of oxygen you take in -- I'd hate to see you wake up dead!
  
  I'm working on a more complex version of the Brain Machine that is specifically for helping people sleep. Like your proposed project, mine will use a comfortable fabric sleep mask and use surface mount LEDs. I'll have all the electronics sewn into the mask, including a rechargeable battery and small speakers. The firmware for this version will use PWM to enable the sound to fade out at the end (as well as independently vary the amplitude of all of the generated brainwave frequencies during the sequence).
  
  All the best with your project!
  Mitch.
  

  Posted by maltman23 on May 17, 2008 at 11:57:55 Pacific Time

• Brain Machine making workshop in Philly
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  For folks in the Philly region, I'll be giving a Brain Machine making workshop at The Hacktory, a new hacker space in Philadelphia. The workshop is on Saturday, May 10th, from 10am to 5pm.
  http://thehacktory.org/classes/brain-machine-workshop
  
  Mitch.
  

  Posted by maltman23 on May 08, 2008 at 00:53:39 Pacific Time

• OCR1A
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  What's OCR1A and what does it do?

  Posted by Always Tired on May 04, 2008 at 17:57:37 Pacific Time

• OCR1A
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  Hi Always Tired,
  
  OCR1A is the Output Compare Register for Timer1. It can do a bunch of things, but the way the firmware sets things up for this project, when Timer1 counts up to the value in OCR1A, the Timer1 output pin toggles (i.e., goes high if it was low, or goes low if it was high), thus generating a square-wave output on that pin. We use it to generate audio, at the frequencies that we want.
  
  The details are described in the firmware documentation I wrote up -- to access that documentation click on the link, above (above the photo), that says, "SLM Documentation".
  
  Mitch.
  

  Posted by maltman23 on May 08, 2008 at 00:48:26 Pacific Time

• sound problem part 2
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  Hi again,
  
  I have an update. I used a multimeter and could not find any issues with it. I decided to go on a youtube search to see if I can see the various stages of the project. I found a link called "brain machine party" This features a bunch of people and Mitch assisting a group of people with making the brain machine. I am able to do the "V"s step as Mitch demonstrated. I still believe my sound is not right. However, after listening very carefully with high end headphones, the volume is lower in one ear. It does seem to make some subtle tone changes as well! However, it never stops, it is looping constantly. I was able to find a youtube link where someone has made a brain machine and shows the unit in action! Again, I tihnk my sound is different from his, I hope I am wrong! I just wonder if I have made some error with the headphone steps. I used some thicker wire than the 30gauge recommended in the parts list. Could that be the problem? The pictures posted in my other post show the thickness of the wires used in the connecting of the speaker connector. I wonder if the capacitors must be placed in a certain way? I figured they had to be and just mimic the same setup for the LEDs beside them. The step of updating the microcontroller for sound requires the downloading of special firmware made my Mitch. The firmware posted on this website only contains two files the makefile and the slm.c. There is no slm.hex. The delete step fails obviously since no slm.hex exists. The next step creates the slm.hex. I wondered if this is just to make sure that the wrong slm.hex does not get programmed onto the brain machines microcontroller. I also downloaded the alternate firmware on Mitch's offical website and noticed a lower tone volume but still doesn't sound right. Hope this description is more helpful. Thanks again.

  Posted by a2lloyd@gmail.com on April 25, 2008 at 07:50:18 Pacific Time

• sound problem part 2
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  Hi a2lloyd,
  
  Sorry for the delayed response -- I just got back from China.
  
  I think that your Brain Machine may be working -- in any case, it is very close.
  
  The wire thickness is not a problem at all. And the capacitors can go in either way -- so no problem there, either.
  
  You mention that when you programmed in my updated firmware that the pitch was lower. That is a good sign, since the only difference with my updated firmware (on my CornfieldElectronics.com site) is that the frequencies are all an octave lower than the original firmware from this webpage. (I did that because the higher pitch was a bit too much like buzzing mosquitos.)
  
  The firmware should take about 14 minutes to go through the entire sequence of brainwaves (with the pitch of the sound and the blink rate of the LEDs changing every so often along the way) and then stop. Could you time yours and see how long the entire sequence takes before it turns itself off?
  
  If the timing is OK, then the only thing that can be wrong is the way you connected your headphone jack. Make sure that the ground wire is connected to ground on the board, and make sure that the ground wire is connected to the ground terminal on the headphone jack. Then the two other terminals on the headphone jack each go to one of the leads of the capacitor -- make sure that each terminal is connected to a different capacitor, and that there is no short between the capacitor pads.
  
  Please let me know how it goes.
  
  If by any chance you will be at the SF Maker this weekend (May 3rd and 4th), then come by my booth, and we can make it work.
  
  Mitch.
  

  Posted by maltman23 on April 29, 2008 at 06:25:57 Pacific Time

• sound problem
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  Hello!
  
  I am currently stuck with my brain machine project! I got stuck on step 2f. You say that you will hear sounds, well I hear the same sound on both left and right speakers of the headphones! I think I am doing something wrong. I had no trouble with the flashing of the firmware. I thought that I screwed up the R5 and R6 because I put them in backwards (brown on the right side of the r5 and brown starting on the left side of the r6) I have extras, so I pulled out one and put a fresh back in the same way. This did not solve the problem. I am including a large amount of pictures to help diagnose the problem. I had a ton of fun building this amazing invention! Great job!
  
  Here is a zip of 6 closeup pictures.
  
  http://www.sendspace.com/file/6lc3h8

  Posted by a2lloyd@gmail.com on April 20, 2008 at 15:07:07 Pacific Time

• sound problem
  You must be logged in to reply.
  
  
  Thanks for the prompt reply. I checked the various threads and I believe something is wrong with my setup. Possibly bad soldering? I looked at someone who posted the audio/video to google videos, my sound is nowhere near the output on mine! Its the exact same sound! I guess I should check the connections with a multimeter. Thanks for your help.

  Posted by a2lloyd@gmail.com on April 21, 2008 at 05:00:30 Pacific Time

• sound problem
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  Hi a2lloyd,
  
  Sounds like you have almost everything working. And maybe you actually have everything working.
  
  The sound should be coming out of both speakers, and the pitch out of each speaker should be close, but slightly different -- with one ear having a very slightly higher pitch than the other. Is this possibly what you are hearing?
  
  Resistors are not polarized, meaning that it does not matter which way you solder them into the board.
  
  But it does matter how you solder the wires on to the three terminals of the headphone jack. The headphone jack has one terminal that is offset from the other two, and this terminal is the one that needs to connect to ground (the blue wire in the photo in the MAKE article). The other two are the left and right speaker, and it doesn't matter which is which for this project.
  
  Unfortunately, I am not able to get your pictures. Maybe it is because I'm in China at the moment?
  
  Does what I wrote help you out?
  
  Mitch.
  

  Posted by maltman23 on April 20, 2008 at 22:57:50 Pacific Time

• can't program my kit :(
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  I've built the minipov3 kit precisely to the ladyada website design, save LEDs 1-4, R5 and R6. The lights flicker in sequence with a short pause after each cycle.
  I then installed the January 07 version of AVRdude and unzipped the firmware files to C:\slm.
  I turned off the kit, plugged it in to one of my two serial ports, then turned it back on.
  When I get to typing "make program-mypov", howevever, I get an error message. Here's what my screen says:
  C:\slm>make program-minipov
  avrdude -p attiny2313 -i 10 -P com2 -c dasa -U flash:w:minipov.hex
  
  avrdude: AVR device not responding
  avrdude: initialization failed, rc=-1
  Double check connections and try again, or use -F to override this check.
  
  avrdude done. Thank you.
  
  make: *** [program-minipov] Error 1
  
  
  
  
  I've tried changing the com port in "makefile", but that hasn't helped. I've looked at every post in response to the project here, and none seem to address this specific issue. Does anyone have a clue why I can't program this kit, and thus why I can't see some sweet visualizations?
  Thanks :D

  Posted by Travoid on April 13, 2008 at 13:50:51 Pacific Time

• can't program my kit :(
  You must be logged in to reply.
  
  
  There could be a few things that might be wrong. But you got the test firmware working, so you are mostly there.
  
  There may be some bad solder connections on the programming parts: the 9 pins of the serial port connector, R10, R11, R12, D1, D2, D3. Also, are any of D1, D2, and D3 in backwards? All of these parts need to have the black bar on the diode match up with the white bar on the board.
  
  You may be using the wrong com port. Check out what com ports are available on your computer, and make sure that the com port number is correct in the makefile. If you are using Windows, you can find the com port number(s) in the control panel, and look under System -> Hardware -> Device Manager -> Ports (COM & LPT.
  
  Please make sure that power is supplied to the MiniPOV Kit when you run the make command.
  
  Mitch.
  

  Posted by maltman23 on April 15, 2008 at 01:58:06 Pacific Time

• LED2 port is dead- need to recode SLM to another port
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  Everything works, the brain machine is ready to go... but the LED2 port (PB1) never worked from the get-go. I soldered the left eye LED to the LED7 port (PB6) instead.
  
  This is fantastic, except that the SLM code points to the non-working PB1.
  
  How do I change the SLM code to reflect my left eye LED on PB6 now?
  
  Thanks so much for the help.
  
  -valerie

  Posted by valerievergen on April 09, 2008 at 12:38:25 Pacific Time

• LED2 port is dead- need to recode SLM to another port
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  Well, I took a guess at which was PB6- they seem to both be blinking at the same rate, though difficult to tell. Please let me know if I have done the right thing before I give someone a seizure:
  
  {
  PORTB |= 0b01000001; // turn on LEDs at PB0, PB6
  delay_one_tenth_ms(onTime); // for onTime
  PORTB &= 0b10111110; // turn off LEDs at PB0, PB6
  delay_one_tenth_ms(offTime); // for offTime
  }
  
  It's just a matter of on and off, right? Does it need to change anywhere else in the code?
  
  -valerie

  Posted by valerievergen on April 09, 2008 at 13:01:04 Pacific Time

• LED2 port is dead- need to recode SLM to another port
  You must be logged in to reply.
  
  
  Hey valerie,
  
  Yay, you got it going! You did exactly the correct thing to change from PB1 to PB6.
  
  Strange that PB1 didn't work. But I'm glad you'll be tripping on your brainwaves with PB6.
  
  Cheers,
  Mitch.
  

  Posted by maltman23 on April 09, 2008 at 13:14:53 Pacific Time

• LED2 port is dead- need to recode SLM to another port
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  Hi Mitch,
  
  Thanks, I'm not too great at all this- it feels good to accomplish. One last thing- the sound in the left ear (PB2) is MUCH quieter than the right ear (PB3). We're talking explosive sound vs. whisper sound. Luckily, my earphones can adjust volume per ear, but the disparity is still quite noticeable.
  
  Is it supposed to be this way, or do I have another damaged port? If so, which of the next ports should I resolder the left ear to? (Oooh... soldering ears now.)
  
  -valerie

  Posted by valerievergen on April 09, 2008 at 13:51:03 Pacific Time

• LED2 port is dead- need to recode SLM to another port
  You must be logged in to reply.
  
  
  Hi valerie,
  
  The volume from the two ears should be the same. Are R5 and R6 both the same? They should either both be Brown-Black-Red-Gold, or both Red-Red-Red-Gold. Also, try checking your solder connections (if they're not already covered in glue).
  
  For the sound you don't have an option of using other port pins, since PB2 and PB3 are the only two pins that output the two times used to generate the sound.
  
  If you reverse the headphone, does the low-volume side switch ears? (Or, is one of your ears way less sensitive than the other?)
  
  Mitch.
  

  Posted by maltman23 on April 09, 2008 at 13:59:01 Pacific Time

• very loud, not much of a 'beat'
  You must be logged in to reply.
  
  
  hey mitch, i built it (hooray for me!) and the lights blink with a tight pattern (looks to be about right) but the sound is not what i expected. one ear is certainly a slightly different pitch than the other, but the noise is somewhat harsh -- it's LOUD, to say the least. Kinda sounds like tonal guitar feedback or like something from an older sci-fi movie (e.g. 2001/Andromeda Strain/Alien). the binaural beat is imperceptible, as to me it just sounds like on (loud) long tone (near the dial tone in frequency, i'd say).
  
  ANother person posted similar results i think, so i'm just asking, This is normal?
  
  Thanks mitch!

  Posted by geodonuts on March 24, 2008 at 14:35:46 Pacific Time

• very loud, not much of a 'beat'
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  Hi geodonuts,
  
  The sound should be a constant pitch in one ear, with the other ear shifting pitch up and down (slightly) as the lights change blink rate.
  
  If the sound is too loud, then you should slide the headphones to the side of your ears until it isn't so loud. If the sound is annoying then it won't be very relaxing (clearly). You can also try some other headphones, since some are louder than others (I wouldn't recommend ear buds, since they'll probably be too loud). You can also try replacing R5 and R6 with a larger value, which will decrease the volume.
  
  (Similarly, if the lights are too bright, then you should slide the glasses down your nose until the light is not uncomfortable. You can also exchange higher value resistors for R7 and R8 to make the LEDs blink dimmer.)
  
  Also, you can try programming in my latest firmware, rather than the firmware from the "official" link near the top of this page:
  http://www.CornfieldElectronics.com
  click on the "maker faire" button, and then find "the latest SLM firmware" link. This firmware is almost the same as the original, but the pitch is an octave lower, which is a nicer pitch than the original 400Hz, which is almost like mosquitos. I recommend using 2.2K ohm resistors for R5 and R6 with the latest firmware (though it doesn't matter too much).
  
  Mitch.
  

  Posted by maltman23 on March 26, 2008 at 19:46:16 Pacific Time

• well never mind
  You must be logged in to reply.
  
  
  actually whatever, i just tried it and it seems about right. thanks anyhow!

  Posted by geodonuts on March 24, 2008 at 20:32:58 Pacific Time

• I Want to Buy a Brain Machine
  You must be logged in to reply.
  
  
  Anyone interested in selling their Brain Machine?
  Thanks,
  Lee

  Posted by capelee on March 17, 2008 at 08:16:17 Pacific Time

• I Want to Buy a Brain Machine
  You must be logged in to reply.
  
  
  I've had so many requests for people who want to buy a Brain Machine already made that I decided to make 10,000 of them. I'm hoping they'll be ready for sale at the Maker Store this summer, maybe as soon as May. If you would like to keep informed, feel free to opt-in to my email list (I send out a newsletter once every month or two or three):
  http://tvbgone.com/cfe_optin.php
  
  Mitch.
  

  Posted by maltman23 on March 17, 2008 at 22:10:28 Pacific Time

• I Want to Buy a Brain Machine
  You must be logged in to reply.
  
  
  Would you recommend this to someone for use in hypnosis induction? and would you know of a good frequency to use?

  Posted by Always Tired on March 22, 2008 at 15:48:46 Pacific Time

• I Want to Buy a Brain Machine
  You must be logged in to reply.
  
  
  Hi Always Tired,
  
  I am not a hypno-therapist, but I would think that this could be helpful. Use half of the sequence to get you deeply relaxed, and then if you want to be, you could be much more susceptible to being hypnotized. Try it and see how it works. And please let me know.
  
  If you really are always tired, then meditating may be helpful for you. I used to be tired all of the time, and meditating has been helpful for me to have more energy in my life. (I also had to be more aware of what I ate, and avoid foods that I felt more tired afterwards).
  
  Mitch.
  

  Posted by maltman23 on March 22, 2008 at 16:59:09 Pacific Time

• I Want to Buy a Brain Machine
  You must be logged in to reply.
  
  
  Yay, it came in the mail today. I might have some results for you by tomorrow.

  Posted by Always Tired on March 28, 2008 at 21:16:11 Pacific Time

• I Want to Buy a Brain Machine
  You must be logged in to reply.
  
  
  Now that i'm done procrastinating this, I built it, it works, but it doesn't really doesn't affect me in the ways I thought it would. It's too weak.
  
  I went for an EEG once, and when they put a strobe to my eyes and got to a certain frequency I started feeling myself go under. I'm just not getting anywhere near the results I was hoping for. D:

  Posted by Always Tired on May 03, 2008 at 01:06:42 Pacific Time

• I Want to Buy a Brain Machine
  You must be logged in to reply.
  
  
  By the way,
  My email is capelee@gmail.com

  Posted by capelee on March 17, 2008 at 08:17:11 Pacific Time

• not using kynar wire
  You must be logged in to reply.
  
  
  can i use 20-24 gauge wire that i found lying around or do i absolutely need the 30 gauge stuff? will the voltage be that much different with slightly fatter wire?
  
  just trying to save myself about six bucks. thanks!

  Posted by geodonuts on March 15, 2008 at 11:53:43 Pacific Time

• not using kynar wire
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  Hello geodonuts,
  
  I like the 30 guage mostly for aesthetic reasons -- it's small and not very obtrusive (I also like that its insulation doesn't deform when you heat it). But the electrons won't care if you use larger wire. I'd still recommend using at least two different colors so that you don't accidentally wire up things incorrectly.
  
  Mitch.
  

  Posted by maltman23 on March 15, 2008 at 15:01:24 Pacific Time

• To Slow
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  I build the machine, but the blink rate is about once a second.
  pls help

  Posted by paul32 on March 13, 2008 at 06:58:20 Pacific Time

• To Slow
  You must be logged in to reply.
  
  
  Hey Paul32,
  
  It might help if you gave me a bit more to go on. What else does it do. What steps in the project did you complete? Did you program in the SLM firmware? What does the audio sound like? Give me a bit more to go on.
  
  Mitch.
  

  Posted by maltman23 on March 13, 2008 at 09:00:20 Pacific Time

• Frequency measurements
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  Hi Mitch. Here are the results of my oscilloscope measurements:
  
  6734-6,749 Hz
  12,48-12,5 Hz
  ~2,49 Hz (short time to measure in the standard-program)
  16,18-16,23 Hz
  
  Youre a bit too fast most of the time. Perhaps you could use an external clock source in order to achieve more accurate timings.

  Posted by Pink_Goblin on March 03, 2008 at 11:25:50 Pacific Time

• Frequency measurements
  You must be logged in to reply.
  
  
  Your measurements are pretty close to the target frequencies of 14.4Hz, 11.1Hz, 6.0Hz, and 2.2Hz. Your Brain Machine is less than 1% too fast, which is pretty good. Each measurement is still well within the range of Beta, Alpha, Theta, and Delta, respectively. There is no need, but if you would like to get more accurate, then you can add an external crystal or ceramic resonator. You'll then need to change the fuse byte in the microcontroller to let it know how to power on with the external source instead of the internal oscillator.
  
  Mitch.
  

  Posted by maltman23 on March 03, 2008 at 19:41:51 Pacific Time

• Frequency measurements
  You must be logged in to reply.
  
  
  Sorry, I meant to say 11%. The timing is still within bounds of working well.
  
  Mitch.
  

  Posted by maltman23 on March 03, 2008 at 19:45:10 Pacific Time

• Brainwave Sequence Editor
  You must be logged in to reply.
  
  
  Many thanks to Armin Bajramovic, who emailed me with software he wrote that makes it incredibly easy to create your own Brainwave Sequences for your Brain Machine.
  
  With this software you can create a Brainwave sequence visually, and at the click of a button it will create the firmware code that you just copy and paste into your Brain Machine firmware file (slm.c).
  
  Here is a screen shot:
  http://www.tvbgone.com/mfaire/slm/ArminBajramovic/screenshot.png
  
  And here is a link to the software (for Windows and Linux):
  http://www.tvbgone.com/mfaire/slm/ArminBajramovic/SLM_Sequence_editor.zip
  
  Enjoy,
  Mitch.
  

  Posted by maltman23 on February 25, 2008 at 23:19:28 Pacific Time

• New project
  You must be logged in to reply.
  
  
  I plan on using my spare parts left over from this project for my own little idea, but I don't know enough about electronics to figure it out on my own. I'm working for a new independant coffee shop called BrewNerds and I want to wire my name tag to have a few blinking LED's on it. So, I have some of the LED's, the same ones used for the Brain Machine. I also have a bunch of capacitors and resistors. If I want to make a circuit so that a LED in my name tag can have a wire that runs down through/behind my apron and into my apron pocket, where the batteries and whatever necessary components would go, how would I wire the circuit? I have a case thing for 2 AA batteries (same as the one in the brain machine) should that run to a resistor, then a capacitor, then the, lets say, 2 LED's and then back down to the batteries? Would this succesfully make it blink?

  Posted by cdxnolan on February 23, 2008 at 20:38:23 Pacific Time

• New project
  You must be logged in to reply.
  
  
  Your want to make LEDs blink using only a battery, a resistor and a capacitor? Sounds like McGyver to me, dude. You can't do that unless you use two Transistors (http://en.wikipedia.org/wiki/Multivibrator) or an NE555 (http://www.kreatives-chaos.com/images/157t.png) or something like that.
  
  What about using blinking LEDs?
  
  http://www.lumex.com/pdf/SSL-LX5093BID.pdf

  Posted by Pink_Goblin on February 24, 2008 at 02:01:48 Pacific Time

• New project
  You must be logged in to reply.
  
  
  Yeah, using 555 chips is a cool way to blink LEDs. Or, now that you know how to use microcontrollers, and since they're so inexpensive and fun to use, why not buy another ATtiny2313 and program it to blink all sorts of LEDs, and you can really go to town?! :)
  
  Mitch.
  

  Posted by maltman23 on February 25, 2008 at 22:07:42 Pacific Time

• Firmware runs too fast
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