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Showing posts from September, 2019

Song Melody Recognition Research

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Make your Arduino dance to a little tune (or just pass on the message)  Someone with a Samsung washing machine wanted to be able to receive the "all done" notification from the other end of their house.  Here's a video sample with some owners interacting with their washes.   I didn't turn up a straightforward solution that I could easily implement (it's a lot easier to get music converted to drive a MIDI keyboard) there is plenty of reference material that should lea someone else to a solution .  Considering the usage time saving to code development time, it might be most practical to just put a wireless baby monitor near the washer. After glancing though some example projects and academic papers, I concluded that my solution would simply use a tempo-measuring-like setup measuring the interval between notes, if the sound impulses matched the tempo of the song I would call it a match (on review, the notes are not as staccato and easy to separate as a mu

Another Cool Board Maker, New to Me

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     I just ran across the Odroid Computer family, by a company in business for some years. Made by hardkernel.com ((South Korea) Their Raspberrry Pi-like boards run Linux and Arduino . (fun to have a Gigahertz speed Arduino , hopefully in Arduino mode, real time code execution is predictable) Their newest model the ODROID-XU4 has an ARM® big.LITTLE Octa core processor. It runs Ubuntu 16.04 and Android 4.4 KitKat, 5.0 Lollipop and 7.1 Nougat.  (You can make a multi-system boot setup.)  Benchmarks show the processor to be 7+ X faster than a Rasberry Pi 3.  Due to the 2 Ghz.  Cortex-A15 cores on the $49 board.  ( 2 - Big 2 Ghz cores,  2 - little 1.4 Ghz cores) While the Ras Pi System on Chip components are made by Broadcom (Irvine) the Odroid chip is made by Samsung (South Korea)  Their Raspberry Pi like boards have a 40 pin GPO connector with Power, Ground and some signals matching the Pi's. See their Wiki pages for more down and dirty details I ac

Technical Information Sources

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This is the start of an occasionally updated info link list..    Some links are to sites that somehow are providing access to academic papers that are usually sold at a significant cost, it is annoying to have to pay $15-$50 for a decade old article on some obscure algorithm development at a taxpayer funded facility.    There is a documentary on one guy (who contributed to the development of the internet) who was an advocate for freedom of information, he ended up caught in legal action that did not go well for him. "The Internet's Own Boy: The Story of Aaron Swartz"    (Prosecuted by MIT for Scholarly Journal “Piracy”) The full 1:45 documentary is on Youtube  (His speech on the subject is at @37.34) Academic Papers Sites :  hobbydocbox.com (google search finds 111,000 docs)                                          intechopen.com     (Open Access: Physical Sciences, Engineering and Tech)                                                                  

E-Paper Displays, Pros and Cons

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I got an e-Paper display to experiment with, the  2.9" SPI module I choose, the Amazon warehouse price turned out to be near $2 cheaper than the Chinese maker's store price , strange...  E-Paper technology uses no backlight, it gives the appearance of paper using colored particles suspended in oil, they are low power devices, in fact they retain an image with no electrical connection.  The disadvantage of this sort of electro-mechanical thing moving around particles is a slow update rate, standard black and white displays like used in ebook readers update a page in about 2 seconds. which is tolarable for just advancing an ebook page, but the slow responce makes normal user interface designs clumsy. Waveshare.com is a big supplier of raw displays an display modules in several forms.  The generic SPI module I chose was about $5 less than the Raspberry Pi hat version and is compatible with several devices. The various waveshare modules appear to use the same basic circuit, th