
Teensy USB Development Board - 16MHz, $19 - andreyf
http://www.pjrc.com/teensy/
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dcurtis
What practical use does this serve? Just for fun hacking?

For anything of significant use, I think you need something like the Beagle
Board (beagleboard.org) or a Gumstix. Anyone know of any others?

~~~
davi
Looks like fun to me.

I know very little about hardware hacking but I had an idea the other day: I
wanted to rig a mini-stoplight up (green, amber, red LEDs) that I could plug
into my computer's USB port and hit hot keys to change which LED was lit.

Then my wife could look over and see if I was super-focused or not. When I was
thinking about code or trying to do science writing, I would toggle the thing
to the red LED; when I was screwing around on HN, I would toggle it to green.

I looked around naively but couldn't find something small & easy. This product
could maybe fit the bill nicely.

Whether my wife would appreciate such a thing is another matter. :)

~~~
Xichekolas
Bonus if you write some code to detect your activity (based on active
application or typing/clicking patterns or who knows what) and then
communicate via usb to your stoplight.

At that point, you could probably sell the thing on thinkgeek.com and watch
cubicles everywhere fill up with activity indicators. Of course, there would
have to be manual override, so cube workers could set it to red all day when
they don't feel like doing anything.

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davi
Nice. Maybe let user build rules like:

When a Terminal window is in the foreground and has an open ssh session -->
amber

When Firefox in foreground, displaying news.ycombinator.com --> green.

Never automatic red, though: I would want to conserve its signaling value, so
that it would always mean, "if you talk to me right now you are going to mess
up a thought structure that was difficult to build".

[edit:

Hm, a little bluetooth-enabled one of these actually would be a pretty cool
thinkgeek product.

]

~~~
GHFigs

      -- In AppleScript while I wait for tea to steep...  
      if application "Terminal" is frontmost then
      	tell application "Terminal"
      		get name of first item of windows of it
      		if result contains "ssh" then
      			set red to false
      			set yellow to true
      			set green to false
      		end if
      	end tell
      end if
      
      -- or a one-liner...  
      if application "Terminal" is frontmost then tell application "Terminal" to ¬
      if (name of first item of windows of it contains "ssh") then set stoplight to "yellow"

~~~
jrockway
This is even easier with a window manager like Xmonad, since you can configure
it to "log" state changes. No polling necessary.

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ComputerGuru
Can this device communicate via USB during runtime or is the USB port only
there for programming purposes?

~~~
ComputerGuru
To answer my question:

The Teensy's USB port is multi-purpose. If the HalfKay bootloader is activated
(via a push-button on the board), the USB port is used for firmware-
manipulation purposes. HalfKay lives on the EEPROM.

Once the device is powered off then on, the USB port is used as a normal
communication device and can be fully utilized to speak with the PC or other
USB peripherals. USB communication code is in your program and lives on the
FLASH.

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lacker
In a few years, naming the product "Teensy" will seem ironic.

~~~
akd
Not really. Further shrinking of that board is constrained by the number of
I/O pins required, whose size cannot shrink because of the limitations of
human solderers.

~~~
zain
In a few years, your comment will seem ironic too ;)

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ars
Only if we switch to using iron based solders (or solderers)..... :)

~~~
Tichy
Maybe we'll all have tiny micro-assembly bots and rapid prototyping printers
that can also print electronics, so nobody needs to solder anymore.

~~~
palish
Maybe someone will invent magic, and we'll be able to _abacadabera_ in pea-
sized 10ghz processors!

My dad told me once that some people from his generation were positive we'd
have colonized the moon by 2010...

~~~
jacquesm
your dad was probably quoting people that were not taking in to account the
various money sinks that ate up the funds that could have been used to make
that happen.

Wars and such...

~~~
ars
That's not it. It's not about the money - it's about the interest. There is
just no reason to colonize the moon, so no one did.

~~~
ConradHex
There is a compelling long-term reason to colonize the moon: to solve the
issues we need to solve to expand to other solar systems.

If we don't, it seems totally possible that at some point a large-scale
disaster on Earth could wipe out all human life.

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goodgoblin
I wonder if this can be used to create Halloween Haunting effects - i.e.
playing a sound when an IR trigger is ...triggered. I would love to embed
something like that in a scarecrow with a crazy mask sitting on my front porch
in a rocking chair. Kids come up - trip the IR - and the eyes light up and it
says 'Happy Halloween MUHAHAAHAHA!!!!.

~~~
mattmichielsen
It definitely can.

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jws
Well fine. If you are going to sell me one laid out better than I managed and
assembled for less than I can have the board fabricated and the parts
purchased for a lot of 10 then I'll just have to buy your product instead.

I was close though. About 10% larger in area.

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sh1mmer
I heard way more people doing stuff with the Arduino.

Do people know how Teensy and Arduino compare?

I do know that Arduino is 100% Open Source which is why so many cottage
electronic outfits provide them premade.

~~~
jws
Comparing to arduino:

* Teensy has a native USB, much faster than the USB/serial bridge of an Arduino. I also find the discrete transaction nature of USB easier for communication, though good old fashioned serial is easier for many people to integrate on the host side.

* Arduino has analog inputs, the chip in Teensy does not. If you need analog you can either add an analog converter chip, or go ghetto and use a digital pin, a resistor, and a capacitor and time how long it takes to recharge after you flush the charge. Drawbacks abound.

* Arduino is a complete environment tailored to easy uptake. This is the _most_ important point of Arduino. You can take someone who does not know what a compiler is, and in minutes they can be in control of hardware. The brilliance of Arduino does not show in the bullet list, it is brilliance by omission.

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dbul
I was just about to look for a brain for my robot. Excellent! The only concern
I have is that the AVR is soldered down; it won't do unless there is a socket.

~~~
jws
I don't think any of the AVR USB microcontrollers come in a DIP format.
Sockets for the available formats tend to be pricey, large (relatively), and
not a good choice for high vibration environments.

Why do you worry about being soldered down? I suppose if you are going to
accidentally blow the chip it is a cheaper repair, but with a cheap hot-air
unit and the video tutorials at SparkFun you should be able to replace that
chip if you like. (You will have to figure out how to load the initial
bootloader if it is different from the one supplied by AVR, but AVR's is
sufficient.)

If you do blow a pin, it probably isn't a total loss. I was winging a little
change to just such a processor and ran a 24v line to a digital pin. The pin
stopped working, but the rest of the chip continued just fine. The moral is
for prototyping you can just use different pins, learn your lessons, and your
final deployed unit should be fine.

~~~
HeyLaughingBoy
And with proper design you won't blow the chip. Let me rephrase: with proper
design, the only thing that will blow the chip will blow the entire board!

Even so, if you do it's only $19!

~~~
jws
Proper design doesn't cover: "Oh look, I can also monitor the 24v battery
level if I stick a little voltage divider onto this extra pin" followed by
soldering the pin to the wrong end of the high resistor 30 seconds later and
powering up.

Frequently these breadboard type computers get accidental shorts from large
fingers or are attached to incompletely specified devices ripped from old
equipment. That's the only pin I've ruined in many projects and lots of
breadboard work, but it happens. It's nice to know I can just move to the next
extra pin and continue.

~~~
HeyLaughingBoy
[Shrug] At risk of sounding like a curmudgeon: learn to be careful, this isn't
software.

With experience some things become second nature: no loose conductors on the
test bench; double check before powering up; test one change at a time; add a
temporary BIG resistor to any input that's over the PS voltage, don't change
connections with power applied, etc.

Ask me how I know that EPROM based devices release a pretty purple flash right
before the smoke comes out :-)

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nas
Neat. I've had good luck with Olimex stuff, for example
[http://www.sparkfun.com/commerce/product_info.php?products_i...](http://www.sparkfun.com/commerce/product_info.php?products_id=29)
. You need to buy a parallel, usb, or serial programmer as well but that's a
one time cost.

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kragen
Awesome! How do you use it in Linux?

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samlittlewood
<http://www.pjrc.com/teensy/loader_linux.html>

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kragen
Great, thanks! I wonder if there's a free-software approach too.

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samlittlewood
Digging a bit deeper, yes:

<http://www.pjrc.com/teensy/loader_cli.html>

Has the source to a command line downloader (GPL)

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mbowcock
I've used these in the past - <http://www.ti.com/msp430> \- I believe they
have lower power requirements than the AVR (at the expense of less memory).
Does anyone know if the AVR has a external memory controller?

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jws
That AVR does not, but they come in other variants with much more memory and
ones that allow external memory (though at the expense of many pins).

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Devilboy
Could anyone recommend a cheap, small GPS unit that would work with this?

