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1906  Community / Bar Sport / Re: Your latest purchase on: July 12, 2013, 11:02:01 pm
Got another order in with Yourduino.
Note that the chips and thermistors are package of 5 for from 75 cents to $1.50.

Order Summary:
Qty    Price    Subtotal
2.4GHz Transceiver Low Power nRF24L01+
2    $2.75    $5.50

AC Line Power Supply: 9V 1A
2    $3.00    $6.00

AC Line Power Supply: 3.3VDC 2.5A
1    $4.50    $4.50

5.5mm x 2.1mm Plug for Arduino External Power Connector
4    $0.35    $1.40

LM324 4x opamp (single supply) (Pkg of 5)
2    $0.75    $1.50

LM386 Audio amp low-voltage (Pkg of 5)
2    $0.75    $1.50

NE5532 Low Noise Dual Op Amp (Pkg of 5)
1    $1.50    $1.50

74HC165 8x Parallel-In Serial-Out Shift Register (Pkg of 5)
1    $1.50    $1.50

Thermistor 10K (5ea)
1    $1.25    $1.25

AC Line Power Supply: 5V 1A
1    $2.50    $2.50

Subtotal:    $27.15
Shipping:    $15.00
Tax:    $0.00
Total:    $42.15
1907  Community / Bar Sport / Re: "The Physics Problem" on: July 12, 2013, 03:28:15 pm
It's actually a bit more complicated about the point where your knee, foot, ankle or part of the side of the bike fulcrums support for the mass of the bike.

Models are fine as models but reality has ALL the details.
1908  Community / Bar Sport / Re: 3D gun printing good or bad on: July 12, 2013, 03:16:43 pm
Don't know Michelle Bachman,

please enlighten the non-US folks...

I envy you for not knowing. You can just turn away now or take a glimpse into madness....

Search on Michelle Bachmann fact check

She was a Tea Party 2012 candidate running on a farther right than thou ticket. If Sarah Palin was too intellectual for you then Michelle would be your girl.

50% of the people have a below-median IQ.

And they know just what the country needs. Rejection of science and a return to theocracy.

1909  Using Arduino / Programming Questions / Re: Arduino and HTML Buttons on: July 12, 2013, 02:51:26 pm
Please edit the quote tags around your code to code tags. It's not your fault the official IDE still uses a broken method but broken =is= broken.

       client.print("<button> type = "button" name = "Download" onClick ="")>Download</button>");[/color]

To print literal characters like " you need to put a backslash in, \". Otherwise "<button> type = " gets compiled as the string to print and the rest gets read as garbage.

Add: any code you're not rock-solid sure of, test it in a small test sketch where it isn't one possible error of many.
1910  Using Arduino / Programming Questions / Re: Adding hardware devices in software dynamically on: July 12, 2013, 02:37:11 pm
You could set it up to be capable of running some number of devices and then add or remove those dynamically, assuming you have power and wiring worked out.

UNO has 2k or RAM. MEGA2560 has 8k. That's for everything, heap (including buffers) and stack.

Dynamic memory -can- be done on an UNO much in the same way that you -can- put a dirt bike track in the back yard of a 1/4 acre home lot.

1911  Using Arduino / Programming Questions / Re: Question about manipulating Strings? on: July 12, 2013, 02:09:26 pm
Given UDP is a String format I am not sure of how to go about doing this.
Given that the first part of this statement is completely false, you might need to rethink your problem. YOU are stuffing the string into a String. Stop doing that, and learn to deal with strings.

I didn't check. I should have known better.

Arduino examples involving text use Strings.

Idiot mode: ON
MCU's are just smaller computers, right? Focus on "portability", not "hardware". What's good on one should be good on the other. If you can do it at all then that's the way to go. If it doesn't fit then buy a bigger MCU, problem solved!
Idiot mode: OFF
1912  Community / Bar Sport / Re: 3D gun printing good or bad on: July 12, 2013, 01:55:38 pm
You live in the state that has Michelle Bachmann for a congresswoman.
1913  Community / Bar Sport / Re: "The Physics Problem" on: July 12, 2013, 01:52:39 pm
Mad Scientist, hope you remember to put centripetal force in there? It's a biggie on a 500+ lb bike cornering at high speed.

I'm amazed there's no gyroscope/accelerometer to give warnings to the rider that they've about to hit point of no return...

some kind of buzzer to alert the rider....

Usually the point where you have to lift the inside foot because the peg is scraping provides a clue that that's all the lean you're going to get. On my bikes I could lean less to the right because the pipes scraped a bit sooner.

Human gyro/accelerometer is feeling where the G's are pushing. It should be directly into the seat but you can shift it a bit to get the bike more upright if you can lean yourself more into the turn which is hanging over the line just a bit btw.

The accident was determined by the entry speed to the turn. Warnings after that just let you choose to go down or leave the road on the outside of the turn.

1914  Community / Bar Sport / Re: 3D gun printing good or bad on: July 12, 2013, 01:35:34 pm
There's at least one Youtube out identifying phone lines as a FREE 9V power source. If the land lines go out, it's probably someone local with very short reasoning capability but "smart" enough to tap the line.
That's the same kind of "smart" that views sink drains and trash cans as black holes for waste. All the stuff you throw out, drain or flush just goes away, right? Whatever we have will always be there, whatever we throw out simply disappears.

1915  Using Arduino / Programming Questions / Re: Running independent from the computer on: July 12, 2013, 01:21:01 pm
USB supplies 500 mA 5V. What do you expect?

Add: Arduino can have up to 200 mA drawn through it. USB gives enough to cause trouble if you don't care about current drawn =through= the Arduino.

1916  Using Arduino / Programming Questions / Re: Question about manipulating Strings? on: July 12, 2013, 04:38:04 am
Out of the three Arduino's I have thus far two are Mega 2560 with W5100 Ethernet Shield and one Nano with a funky ENC28J60 Ethernet Shield that is not supported by Arduino. (Major pain in the ass to configure but libraries have a small footprint.)

The main concern is RAM. UNO has 2k while MEGA has 8k. Strings need space to copy themselves every time they change length. But with the extra RAM you're probably safe, just don't push it without running an occasional check.
Also be sure to find out if free() has been fixed in your IDE or get the unofficial fix. If it isn't fixed and you don't get the fix then maybe extra RAM only == extra time before the crash.
This sketch has a simple RAM check function and shows how to put constant text into flash (PROGMEM) so it doesn't get copied to RAM on startup.

#include <avr/io.h>
#include <avr/pgmspace.h>

const char PROGMEM textTable[] = { // all this text stored in flash

PGM_P tT; // will point into namesTable

const char textTable[] = { // all this text goes into RAM

void  printProgstring( PGM_P FM )
  byte fb;
    fb = pgm_read_byte( FM++ );   
    if ( fb )  Serial.print( fb );
  while ( fb );

int freeRam () {
  extern int __heap_start, *__brkval;
  int v;
  return (int) &v - (__brkval == 0 ? (int) &__heap_start : (int) __brkval);

void setup(void)
  Serial.begin( 9600 );
  Serial.print( "/n Free RAM = " );
  Serial.print( freeRam());

  tT = textTable;
  printProgstring( tT );
//    Serial.println( textTable );   
    Serial.println( );   

void loop(void)

1917  Using Arduino / Programming Questions / Re: quick bitwise question regarding << operator on: July 12, 2013, 01:15:57 am
There are some extra functions for people less than comfortable with shift operations.
About halfway down on the right, look for
Bits and Bytes


but IMO those can keep you from needing to learn bit masks and can make for clunkier code.
1918  Using Arduino / Programming Questions / Re: Need guidance on a ladder type sequence on: July 12, 2013, 01:05:26 am
Are your if arguments laid out right?
if (millis() - ch1Time >= ch1Dur && ch1Final ==0)

vs., i.e.

if (((millis() - ch1Time) >= ch1Dur) && (ch1Final ==0))

&& has lower precedence than >=

joke mode: ON
But besides that, why on Earth would the OP want to make his code more clear to read?
joke mode: OFF
1919  Using Arduino / Programming Questions / Re: Question about manipulating Strings? on: July 12, 2013, 12:44:14 am
If you're running Strings on an UNO and start to get weird behavior and/or crashes then get yourself a Mega 2560 for the extra RAM.
1920  Using Arduino / Programming Questions / Re: Running independent from the computer on: July 12, 2013, 12:36:58 am
Could it be because im using java or because im accessing the serial monitor in my code?

The Java is transmitted text. You do have plans to connect something to the serial pins, don't you? Something that will use the Java?
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