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dynode

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Awesome I’m just doing a POE design now.

- Was having a conversation today about isolation and grounding for POE (product has a metal case). Do you have a reference? Or standard?

- TVS ahead of the bridge right?

- Do you have a part recommendation or reference design for ideal diode POE?

Replying to myself a quote from my article

"It’s easy to notice a bug when examining the colors for Google (note, this is normal google.com not a doodle). Notice how the three colors are light gray, dark gray, and white – not the typical red, green, blue, yellow color scheme. Why? Well, when the image screenshot is resized to 320 x 240 pixels for processing, the colors are dithered. The number of pixels in the new image that lie between red, green, blue, yellow and white – the dominant background color – is much larger than the number of pixels that are colored. Because of dithering, those between pixels are closer to shades of gray, than colors, and thus the k-means clustering (with EM) finds shades of gray and white to be the “color of Google”. I’m not sure if this is a bug.. what do you think?"

Paul, I made something similar - http://bardagjy.com/?p=1639

I had the same problem with Javascript so I used I used Selenium to drive Chrome to take a screencap of the page. Then I used K-Means clustering with EM to convert the pages to their constituent colors.

I scraped 100 and 1000 of the Alexa top 1M. Cool to see another approach, great work!

It's not that bad.. typically you use a 32.768kHz ("watch") crystal then divide by 15 to get one second. You can do it with two chips (a bunch of solutions, one is two 7468).

Some more info - openocd is a not bad open source JTAG server. <http://openocd.org/>

The TL866 I suggested does support your part.

If you've got the flash in a TSOP - another trick for getting at the flash is to find a FPC cable that has the same pitch as your TSOP and solder it down on the board. FPCs with varying pitches are available at Digikey etc. That way you don't have to remove the flash from the board.

First thing to do is have a look at the datasheet <http://www.eonssi.com/upfile/p200892917341.pdf>. I was hoping that it'd be SPI or I2C, but it's a big parallel flash, so reading it is going to take some hardware.

Comes in two packages a TSOP and a BGA. I'm hoping you have the TSOP. If you've got a TSOP, you can get a socket for it / probe it. You can probably also get a socket for the BGA but you might be paying out the nose.

I like the JTAG approach as well. Assuming it's connected to a processor or FPGA that's got boundary scan, even if the rest of the system isn't cooperative you can bitbang the contents of the flash out using the JTAG hardware.

The JTAG silicon - even if it's on the same die as the processor / FPGA is totally separate. It's something like a tiny state machine. Read up on it, really powerful. <https://en.wikipedia.org/wiki/Boundary_scan>

Another option is to transplant the interesting flash from the dead device to an identical working device. Use the working device to read out the contents of the memory. This will require some soldering skills.

Or.. you can pull it off the board, and get a programmer. The industry std is Xeltek but they're $$$$. I've got a TL866, works pretty well. <http://www.eevblog.com/forum/blog/eevblog-411-minipro-tl866-...

Or.. you can read the datasheet and build yourself something with an arduino. You'll run out of pins though, so maybe a pro? or maybe port expanders.

Good luck!

Do you have any links or sources?

I too remember something like that, but was under the impression that CAs are still ok.

But of course, judging by the massive downvoting you've gotten, I suppose you're incorrect. I wish those downvoters would explain their viewpoint rather than downvoting...

Hey that's neat. I worked on something similar back in 2009/2010.

<http://bardagjy.com/?p=614>

We used a G1 dev phone to fly a 1.5 meter wingspan airplane. We used only sensors in the phone, camera, gps, etc.

Honestly it didn't work too well - we needed either a much better model of our airframe, an airspeed (not groundspeed) sensor or an airframe that could power through 10-15 mph winds.

In the end however, we demoed waypoint navigation and imaging the waypoint. You text it lat/long and it texts back a picture.

We did it as a proof of concept (for an interested govt agency), modern smartphones are neat, but bespoke, real-time hw, with navigation grade sensors are probably an order of magnitude more effective (though an order of magnitude more expensive).

Working with android to do robotics was.. interesting. We had to do all sorts of hacking to make the phone behave a little as possible like a phone and more like a real-time controller. What do you do when someone calls the phone while you're flying an airplane? How do you keep the phone application from taking over and exiting out of your navigation app? While the airplane is 1000 ft in the air?

I wrote my thesis with latex + git. Merging can sometimes be wonky, but no wonkier than usual.

I had my sister review my thesis for grammar and spelling, she doesn't do git, so I checked out a coy in a dropbox folder and shared it with her. She made her edits in the folder, and would send me emails as she finished each chapter. After she finished a chapter I would check in her changes and merge the diffs with FileMerge.

Worked pretty well, though we only collaborated on text, I never merged figures or equations. I also had a cron job that would render the head of the master and put it on my website so my advisor and committee members could check in on my progress.

This effect is also used to generate these images http://cvcl.mit.edu/hybrid_gallery/stein_series.html

From the page "In the eight hybrids arranged above, at a close proximity, you will perceive Albert Einstein. Each image carries a shadow of an ulterior individual as well. Stepping away from the images will reveal eight respective identities of notable figures that exist in the low spatial frequency of the images, and Einstein will slowly disappear. Each hybrid carries a dichotomy of fame arisen from diverse disciplines, and a legendary cognitive intellect. The conversion of which gives rise to unique personalities."

Which is why it drives me nuts when people refer to the Raspberry Pi as "open hardware". You can't get even close to the datasheet without an NDA.

They time interleave four Analog Devices AD9288 [0] dual 100MS/s 8 bit ADCs that are over clocked to sample at 125MS/s (so 125MS/s times 8 = 1GS/s).

What's fascinating is a number of people in the HW community have managed to reverse engineer the Rigol DS1052 scope. A Hellene on the EEVBlog forums has lovely pencil drawn schematics [1].

[0] http://www.analog.com/en/analog-to-digital-converters/ad-con...

[1] http://www.eevblog.com/forum/blog/rigol-ds1052e-nasty-surpri...