Show Posts
Pages: [1] 2
1  Using Arduino / Displays / Re: GLCD library version 3 on: April 26, 2011, 03:14:40 pm
kudos, bill.
2  Using Arduino / Installation & Troubleshooting / Re: Can't rewrite 8U2 bootloader on: April 10, 2011, 03:59:50 pm
Code:
lsusb -v -d 2341:0010

lets see what version of the DFU you are running.
3  Using Arduino / Installation & Troubleshooting / Re: Pin 13 Light On on: April 10, 2011, 03:51:55 pm
what operating system are you using, as this will help us try to figure out where the problem is?  Which version of IDE? Is this a homebrew sketch or a basic one?  Does this happen if you load a Blink sketch in?
4  Using Arduino / General Electronics / Re: how fast is a bluetooth keyboard?? on: April 06, 2011, 04:42:00 pm
now this is a bit old, but how about slapping an external antenna on the bluetooth module?
5  Using Arduino / Displays / Re: Ultrasonic Ranging Module HC-SR04 garbage on lcd on: April 02, 2011, 11:57:13 pm
Hey i was wondering if anyone has tried to get mm resolution from this sensor, i wanted to get more accurate readings from these sensors, if there away to access the actusl delay time the sensor reads ? that way i could calculate the distance in mm.
any help, examples would be great thanks

you can do this with the Parallax Ping modules, as the device returns the pulses as durations in microseconds, correlating that to distance...so you can do the math as accurate as you need...(within reason)
6  Using Arduino / LEDs and Multiplexing / Re: Can I use Cat5 cable to wire my lights? on: March 31, 2011, 12:09:56 am
I have routinely used cat5/5e cable for low-voltage switching applications, and have a word of advice.  If you can get your hands on "patch" quality cable, as opposed to plenum cable, do it. 

The patch cable tends to be stranded, the plenum is solid conductor.   Couple of small radius bends in a plenum cable can cause loss of conductivity / increased resistance, and those are a BEAR to isolate / work out, the stranded-patch cable tends to be more forgiving.

The patch cable tends to have thinner / more flexible insulation.

The patch cable is usually cheaper. 

Unless you're worried about any accidental smoke from your project being inhaled in large quantities, go with patch/stranded if you can get it.  Plenum cable has to meet all kinds of building codes concerning fire specification / "air handling" qualities, and frankly isn't worth the bother in this regard.
7  Using Arduino / Displays / Re: NHD-0216K3Z-NSW-BBW on: March 25, 2011, 10:19:11 pm
roffle.

i've had luck with NHD displays, never used a serial model though.
8  Using Arduino / Sensors / Re: Two Ping sensors on one Arduino on: March 18, 2011, 09:28:48 pm
I've bene playing with a Parallax Ping module now for a while, and I've noticed that it excels at large, flat objects and has trouble over 5 feet with cloths, fabrics and irregularly shaped things (ie, People).

Having some understanding of how the arduino has to talk to the Ping sensor, does it absolutely HAVE to be identical pings at the same time?  The Ping has to be triggered, send a burst out, wait for the return, and then send the timing back to the arduino...sooo (hypothesizing) if you were to stagger them by (standby - rapid datasheet math here) 25 milliseconds...you could theoretically have them operate on the same arduino.  For the project that you are proposing, I don't see why this couldn't be accurate enough...

As I see it, if you write code poorly enough, you'll have more delays and slowdown in the coding execution, than you will inaccuracies by the two units being offset by 25 milliseconds...if you write your functions correctly, they can easily compensate for the staggered execution... i think...

is 25 milliseconds gonna kill ya?
9  Using Arduino / Displays / Re: LCD graph? on: March 13, 2011, 10:31:25 am
thx floresta, forgot to mention it's a code snippet.
10  Using Arduino / Displays / Re: LCD graph? on: March 12, 2011, 11:32:30 am
never mind...i got the VPN on my phone to work!

here's what I had

Code:
int barGraphValue(int cm){       
/*  This is purely for the gauge component of the display, the map command maps the values returned in cm
across the range of values for the sump bottom  (limitSumpLo) to the sump overflow (limitSumpHi) to the
range of bar graph values for display. 
*/
  int barGraphMap = map(cm,limitSumpLo, limitSumpHi, barGraphMin, barGraphMax);
    {
    barGraphMap = constrain(barGraphMap, barGraphMin, barGraphMax);
    }
    return barGraphMap;
}


int drawBarGraph(int barGraphLevel){
  GLCD.DrawRect(0,13,17,50, BLACK);                                            // draw outline of bargraph
  GLCD.FillRect(1,14,15,49, WHITE);                                           //white out the entire thing
  GLCD.FillRect(1,(63-barGraphLevel),15,(barGraphMin+barGraphLevel), BLACK); //draw new fill level
  }

As I said before, I knew no C prior to two weeks ago...so this is all self taught, and I'm sure someone else out there can rip this apart in 5 minutes...but it works! :-)
11  Using Arduino / Displays / Re: LCD graph? on: March 12, 2011, 11:24:31 am
I wrote up a LCD bargraph for a sump well meter...

long and the short of it is I mapped the value over a 50 value range

Code:
bgLevel map(sumpLevel, sumpMin, SumpMax, BGMin, BGMax)

and then I drew a box using the GLCD.DrawRect for the outside of the graph, and then drew 2 consecutive GLCD.FillRects (one white, the value of the entire DrawRect in order to clear the previous value (and not do a complete GLCD.ClearScreen) and then the value fill, which was static X dimensions, and for the Y dimension - it subtracted the bgLevel from the bottom Y pixel (so the graph would fill from the bottom up), then left the remainder empty. 

I don't have the code available to me now, and I taught my self all the C I know in the last two weeks...but it does exactly what I want, and it works well.  I can put it in if you want, when I get home.
12  Using Arduino / LEDs and Multiplexing / Re: Is something wrong with my LCD screen? on: March 11, 2011, 07:09:25 pm
The sketch ... (ie the code).

sorry.


you're POSITIVE the connections are good?
13  Using Arduino / LEDs and Multiplexing / Re: Is something wrong with my LCD screen? on: March 11, 2011, 06:08:13 pm
please cut and paste the sketch you are working, that vid/cam resolution gives me eyestrain.
14  Using Arduino / LEDs and Multiplexing / Re: Is something wrong with my LCD screen? on: March 11, 2011, 05:29:39 pm
you have an incompatible setup there.

The LCD you are using is not 16x2, as the code library you are trying to make work requires.  The one you are apparently using is 20x4  The LCD (just from looking at it has 20 pins (making it most likely a parallel data bus)...and you have 11 hooked up.  Obtain the data sheet for the LCD you are using, interface that with the arduino you are using with the required hookups, and then find a library which supports your LCD driver chip.


All you are currently doing now is powering the logic circuit and LCD backlight.
15  Using Arduino / General Electronics / Re: Board-behavior in vacuum, low/high temperature ranges and vibrations? on: March 11, 2011, 04:07:36 pm
Epoxy is not very good heat conductor. There is a product called "Arctic Silver Epoxy" and it conducts heat extremely well. It is expensive, however, you probably don't want to fill your whole enclosure with it.

cut directly from the Arctic Silver interwebs...

Even though Arctic Silver Thermal Adhesive is specifically engineered for high electrical resistance, it should be keep away from electrical traces, pins, and leads. The cured adhesive is slightly capacitive and could potentially cause problems if it bridged two close-proximity electrical paths.


it was a nice idea at the start. If you had a significant heat source, what if that source had a simple heat pipe on it to a radiator?
Pages: [1] 2