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16  Community / Bar Sport / Re: Question about FAQ and Open Hardware. on: June 27, 2014, 01:33:16 pm
The design I$ open source and calls for a "specific" controller because That part meets the design specification
If this is an issue for your design purposes...
Pick one that does... It would also be good to verify that the control software is compatible with your choice of hardware and controller.
Much as the 'original' designer did..'


Doc
17  Using Arduino / General Electronics / Re: nrf24l01+ damage on: June 27, 2014, 04:23:19 am
Are you using level shifters for the control and I/O?... AFAIK the 24L01+ doesn't have 5 v tolerant inputs or power supply

Doc
18  Using Arduino / Programming Questions / Re: attiny 85 (spi,BitBanged...) on: June 22, 2014, 12:58:46 am
It's really Great to be able to read them as a dialog... Most educational..  Thank You.

Doc
19  Using Arduino / General Electronics / Re: Measure High current on: June 21, 2014, 02:57:12 pm
Measuring the drop across a series resistor in the ground leg of a power supply is perfectly do-able but not really advisable unless you have a means of sensing the voltage at the high side of the sense resistor to detect an open condition or all the electronics are TOTALLY isolated from everything AND I DO MEAN EVERYTHING else connected to that node....
IMO a lot of extra crap to emulate the inherent isolation provided by a hall effect device.... Safety is NEVER, NEVER a place to try to save a dollar or "Simplify" a design.
You have been advised of how to do the task 'correctly' the obvious way, Twice...
What is the underlying issue that keeps you asking about how to do something inherently VERY Dangerous.
Were your engineering skills at the same level as your 'apparent' coding skills you would know this and not ask a useless question.
1A @ 1KV is 1 KW... this is a NON TRIVIAL current and voltage and 'accidents or parts/construction failures are generally LETHAL to both the equipment and the operator.
The answer to your question about ground sensing of DC current is perfectly valid... However after 40+ years of engineering experience, Something I would NOT attempt to do... simply because the safety devices added to limit the available fault voltage are subject to failure from the conditions imposed by the measurement techniques... OR.. Are of a nature as to degrade the available accuracy... NOT under ANY circumstances a 'wise' choice

Doc
20  Using Arduino / Programming Questions / Re: got some questions about a code on: June 18, 2014, 10:13:40 pm
Since a flip-flop is a shift register component it would be an interesting and educational exercise to expand that snippet to an n length shift register...

Doc
21  Using Arduino / Programming Questions / Re: Particle Filter with Sensor Inputs on: June 17, 2014, 11:06:31 am
Nor are you going to deal with multipath issues. At the frequencies used radio waves behave much like light. There will be interference zones where the RF (radio) 'waves' will add and subtract, both Time, sign and amplitude.  All of which are more related to reflections than absolute Losition relative to the transmitter. In a manner solar to "Ghosts" seen on old analog television receivers... not, young cricket, a linear change in amplitude that would indicate relative distance...

Doc
22  Using Arduino / Microcontrollers / Re: How do I flash the bootloader on this board? on: June 13, 2014, 03:55:46 am
I went through that issue about 15 years back and I found with the 16CXXX controllers that I lost about 1 in 10 chips.. I tried pre-programmed devices as well as a "Glomper' Chip... Remember them?...  and a connector to the programmer both were less than satisfactory and this fueled my comments... When the second order for that product was placed I got real intimate with  Pogo pins...
I'd like to apologize for my comments about 6 pin connectors. I didn't look at the first picture picture carefully and  "Ass u me d" that the board on the referred web page was the same as the OP was...
Tack Soldering 6 wires to a male two row X three pin header  and soldering them to the relevant pins is for me no big deal.

Doc
23  Using Arduino / Programming Questions / Re: Read variables from SD Card on: June 11, 2014, 05:20:01 pm
It Would take a long time to "Use Up" or wear out the Eeprom... and it does  require less additional hardware..

Doc
24  Using Arduino / Microcontrollers / Re: How do I flash the bootloader on this board? on: June 11, 2014, 04:27:45 pm
The mistake I made was to not look at all of the pictures before offering simple advice that might n\be beyond the technical ability of the OP.
@ Crossroads... on the referenced website this was the picture I referenced http://www.infinity-hobby.com/main/images/article/201402-03xw/20140310xw04-02.jpg. and it clearly depicts a standard 6 pin ISP connector
I do apologize for the confusion I created but my idea is still a possible concept in that 'tack' soldering a 6 pin header to the ISP pins is no big deal...
Certainly less than that fancy clip on device that might be used once... Yes, I'v seen the part in several threads prior to this one and the sales price too.
What I fail to understand is what to do when/if the code is upgraded... scrap the old one or send it to the "Factory" for upgrading?.
IMO that part is a production device most useful to compensate for poor board layout...  IE the lack of an ISP connector
I apologize for missing the photo of "His" board which is apparently much different that the "Solution" proposed on the referred.
website.
I keep a small stripboard with a 6 pin (2 X 3) and 6 small wires soldered to the pins just for that purpose...
WAAAY less expensive than the clip on device that was referenced... unless it is used as a production tool...
And yes I do make or repurpose boards with ATMega328P-AUs...

Doc
25  Using Arduino / Microcontrollers / Re: How do I flash the bootloader on this board? on: June 11, 2014, 11:40:12 am
Why not purchase the hardware mentioned and then follow the instructions in the mentioned website?
There are 6 pins in what looks like a standard ISP header footprint on the PCB which should make the task relatively easy
As a possible method to get around the additional hardware requirements you might solder a six pin (2 X 3) standard male header and connect it to the programmer...
Then follow the rest of the flash procedure mentioned in the website you referenced...
Either do the above or just buy the appropriate hardware mentioned and follow the procedure to flash the new bootloader.
Simple...

Doc
26  Using Arduino / Installation & Troubleshooting / This Program Requires on: June 07, 2014, 05:08:12 pm
at least Java Development Kit 1.5.0...
This is after I downloaded Arduino 1.0.5 R2 and 1.5.6R2. installing 1.5.6 went fine but the 1.0.5r2 installation gives me this message when I attempt to open the 1.05 IDE "This program requires at least Java Development Kit 1.5.0"......
What to do? or what did I do wrong.
The box is a Samsung NP-N150  Notebook with an Intel Atom processor with 1 GB of Ram...
What to do?... I'm lost as 1.5.6 seems to work OK

Doc
27  Using Arduino / Programming Questions / Re: Problems with code for hc-05 bluetooth, dht11 temp sensor and lcd keypad on: June 03, 2014, 12:16:15 pm
Generally it's Very Poor practice... to use the maximum limits for anything except a defined "Drop Dead" point.
I tend (through 45 years experience) to be very conservative... If my design 'requires' more than 25%of the Maximum available pin current then it's time to use a buffer...
Conditions are always variable.. to a degree but your example of 70 mA for a relay coil violates two important ones...
1. Never... Never, Ever exceed the Max rating of ANY parameter... even when you are certain that it Isn't An Issue Whatsoever.
2. NEVER, NEVER, EVER USE A CONTROLLER PIN TO DIRCTLY SWITCH AN INDUCIVE LOAD OF ANY TYPE, even with a back emf diode for protection.
The diode will, if it is fast enough and big enough (to safely dissipate the energy stored in the magnetic field) deal ONLY with the back end... but the surge current from making the afor mentioned magnetic field will exceed the MAX pin current and can very easily be an order of magnitude greater than the "ABSOLUTE MAXIMUM RATING"...
While it 'might' work... there are always unintended consequences...
Remember that there are "Conductors" or "Wires" inside the IC... and quite small ones at that.
High current pulses drop voltage across those "Wires" and those "voltage pulses" created from the current pulses will typically be the source of many types of "undefined behavior" in your code. Noisy power supplies are the most frequent design mistakes...
Small fet's are ideal as buffers... Use them... And use bypass caps , 100 nF as close to the chip as physically possible! and a 1 uF (minimum) bypass for every 2 IC'S ON A PCB or more for breadboard development environment.
Don't forget the diode... while there is a body diode in the fet it generally Isn't a good part for controlling the charge stored in an inductor..

Doc
28  Using Arduino / Project Guidance / Re: current sensing options on: May 28, 2014, 07:36:31 pm
look on Ebay for a Hall Effect Current sensor... ACS712ELCTR-30A-T Hall Effect High Current Sensor
http://www.ebay.com/itm/ACS712ELCTR-30A-T-Hall-Effect-High-Current-Sensor-/161045293860?pt=LH_DefaultDomain_0&hash=item257f0c2b24
Is an example of one and is available from Allegro in 5 to 30 A ranges.
The output centers about Vcc and is I believe a 5V device than can measure current bi-directionally Or AC and DC..
The ACS712ELCTR-20A looks ideal for a 10A sensor... I took the liberty of attaching the relevant data sheet..

Doc
29  Using Arduino / Programming Questions / Re: Arduino Nano and two 32x16 Sure led matrix displays on: May 26, 2014, 02:37:59 pm
There exist several libraries for the 3208/16 Sure display panels I'm using the Gauvravmm library.. with 2 Sure 3208 panels and it works well... I do have some sample code for 2 ,3208 panels. Thanks to Pedro147 as i remember it was originally for one panel but the modifications for two were simple. I'm using a Pro-Mini for the controller and the original Sure controller board for the display PSU. Google shows a bunch of code and library files... Adafruit might also have what you want too... They sell a Nice 3216 3 coloor display as well..
https://github.com/gauravmm/HT1632-for-Arduino

Doc
30  Using Arduino / Programming Questions / Re: Displaying a Keypad on Touch Screen on: May 24, 2014, 10:40:25 pm
There is a keypad sampleUTouch  sketch that works well Too..

Doc
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