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1  Using Arduino / Programming Questions / Re: WiFi Library Inefficiencies? on: January 10, 2013, 08:02:35 pm
Thanks for all the replies.  I did end up not using the String library.  It was way too unpredictable for me.  Thanks again.
2  Using Arduino / Programming Questions / Re: WiFi Library Inefficiencies? on: January 09, 2013, 10:33:06 am
What's the String bug?
3  Using Arduino / Programming Questions / WiFi Library Inefficiencies? on: January 04, 2013, 06:43:45 pm
Can anyone explain this behavior I am seeing?  Using the WiFi library I am seeing the following.

Code example 1 (where client is an instance if WiFiClient):
Code:
client.print("Some text: ");
client.print(someInt);
client.println(" some more text");

Code example 2
Code:
String var = "Some text: " + String(someInt)+ " some more text");
client.println(var);

The first example works very efficiently across the wire and all of the text gets concatenated and sent in a single packet (or two).  However the second code example runs very poorly.  I have some code that is a little more complex than the above example and when written in the style of the first example makes it to the server in 2 packets.  However when written in the style of the second, it sends it in about 6 to 7 packets with a 2 second delay between many of the packets.  And in addition, some of the packets only contained one or two characters of text.  Its very odd to me.  I was hoping to use the second style to create the body of a post (JSON) and make it easy to calculate the content length.  But it was so bad I had to go back to other style.

Any ideas about what is going on here?
4  Using Arduino / Motors, Mechanics, and Power / Re: Custom Power Cable on: December 03, 2012, 12:48:26 pm
This was not so much a cross-post, as a move.  After this question sat in this forum unanswered for quite some time, it was obvious to me that it was in the wrong area.  I moved it (or re-posted) to the other area where it was answered in less than an hour.  Thank you for adding the link back to the other post.

Is there a way to move posts? 
5  Using Arduino / General Electronics / Re: Custom Power Cable on: November 29, 2012, 11:37:45 am
Thank you gentlemen, this information helped a lot.  My cable is working great so far.
6  Using Arduino / General Electronics / Custom Power Cable on: November 28, 2012, 02:28:57 pm
So I posted this on the "Motors, Mechanics, and Power" with no luck.  I wonder if this question is better suited for this forum.  I have been trying to figure this out myself by looking at the arduino schematics, but apparently my electronics chops are not up to the task yet.
__________________________

I am creating my own power cable and wanted to run my thoughts past everyone to make sure I am not missing anything.

I have an old HTC USB charger that I want to use (5V---1A).  I need the cable to run about 10 feet so I am modifying the cable.  I have already spliced in the longer run and am measuring 5.2 volts consistently.  The question is how to connect it to the Arduino on the other end.

My initial thought is to splice a USB type B connector on the end and just plug into the USB connection on the Arduino.  I have a barrel connector I can use as well.  But from my reading, it appears that if you are using the barrel connector, or the Vin, you need at least 7V to have the board running at 5V.

I guess my main question is whether I should be concerned about the power consistency from the HTC charger and well as other potential concerns when running my own power through the Arduino's USB port.  Does it have similar power conditioning hardware as the other power input or am I risking frying my board?  I would think the HTC wall wart would be fairly well made.

Thanks for the help.
7  Using Arduino / Motors, Mechanics, and Power / Custom Power Cable on: November 27, 2012, 12:00:27 pm
I am creating my own power cable and wanted to run my thoughts past everyone to make sure I am not missing anything.

I have an old HTC USB charger that I want to use (5V---1A).  I need the cable to run about 10 feet so I am modifying the cable.  I have already spliced in the longer run and am measuring 5.2 volts consistently.  The question is how to connect it to the Arduino on the other end.

My initial thought is to splice a USB type B connector on the end and just plug into the USB connection on the Arduino.  I have a barrel connector I can use as well.  But from my reading, it appears that if you are using the barrel connector, or the Vin, you need at least 7V to have the board running at 5V.

I guess my main question is whether I should be concerned about the power consistency from the HTC charger and well as other potential concerns when running my own power through the Arduino's USB port.  Does it have similar power conditioning hardware as the other power input or am I risking frying my board?  I would think the HTC wall wart would be fairly well made.

Thanks for the help.
8  Using Arduino / Networking, Protocols, and Devices / Re: Official WiFi shield Network Scan problem on: November 20, 2012, 12:03:20 am
The Arduino WiFi shield seems to work fine on our corporate g only routers (well they are a/g).  It does occasionally have an issue connecting but that seems rare.  The sample code worked as is.  I wish I could give you more.  We did try the DFRobot wifi shield and it did not work at all for us.
9  Using Arduino / Networking, Protocols, and Devices / WiFi.disconnect() not behaving as expected on: November 19, 2012, 11:57:34 pm
I am  in the process of writing some code that is trying to be as power efficient as possible.  I am pleased with what I have written for the Arduino itself, as well as the sensors, but I am struggling with finding ways to reduce the power consumption of the WiFi shield itself.

I did noticed that even with the WiFi shield connected it doesn't seem to be powered (at least none of the LEDs are lit) until the WiFi.begin() method is run, which gave me an idea. 

For a good portion of the day, the Arduino will sit in a powered down state.  As I am putting the Arduino to sleep, I thought if I called the WiFi.disconnect() method it would put it back in the pre WiFi.begin() state.  That way the WiFi shield isn't sitting there maintaining a connection to the AP while the Arduino is sleeping (and therefore hopefully using less battery).  And when I run the command, it seems to disconnect just fine.  However after a few seconds (and while the Arduino is sleeping) it seems to re-connect to the AP all on it own.

Does anyone have any idea how to power down the WiFi shield while I am wanting to be in low power mode?  I have already had the suggestion to power the shield from an external source.  However, at this time I am not wanting to remove the shield from the Arduino itself (the compact connection is one of the reasons we bought the shield).  I am first looking for options that will work while the shield is mounted.

Thank you all for your time.
10  Development / Other Software Development / Power Saving for the WiFi shield on: November 16, 2012, 08:19:55 pm
As directed by the WiFi library reference page, I am posting my request/suggestion here.

It would be really nice if we had the ability to control power state of the WiFi shield programatically.  I am realizing that any power saving features that I may implement in my arduino code may be rendered irrelevant due to the fact that I can't control the power state of the WiFi shield.

Just a hope.  Thanks in advance.  The Arduino WiFi shield has already been 100% simpler than others we have tried.
11  Using Arduino / Project Guidance / Re: Power Saving Options on the WiFi Shield on: November 12, 2012, 03:37:49 pm
Considering the shield is directly attached to the Arduino, I assume powering it manually is impossible without removing it and manually wiring the shield to the Arduino board.  This is not ideal as it adds to the bulk/mess of the unit (part of the reason we opted for the shield to begin with).  Although we have not ruled out this approach, it is not preferred.

So it would appear that there are not any obscure power saving features built into the WiFi shield itself (akin to those built into the arduino). 

I did have the thought that if I just disconnected the wifi from its access point, right before the Arduino was put to sleep, it might reduce power.  I would assume that while the shield is unconnected, it is sitting idle and the radio/device would consume far less power.  But would it be enough?  Has anyone tested the power consumption of the WiFi shield while in various states?
12  Using Arduino / Project Guidance / Re: Power Saving Options on the WiFi Shield on: November 06, 2012, 02:44:10 pm
I want this device to connect directly to our network.  None of those others can do that without an intermediary.  The intermediary is a deal breaker for what we are trying to do.
13  Using Arduino / Project Guidance / Power Saving Options on the WiFi Shield on: November 05, 2012, 03:41:39 pm
I plan to run my project off of batteries and have been doing research on the power saving options on the Arduino Uno itself (sleep functions, etc.).  But the shield seems to continue to run at full power regardless of the state of the Arduino.  So I am feeling like all of my power saving ideas are useless if the WiFi shield is going to suck up all my battery anyway.  I don't see any libraries that deal with the power state of the WiFi Shield.

Does anyone have any ideas about how to improve battery life while using the WiFi shield?
14  Using Arduino / Project Guidance / Re: 802.11g WiFi Shield on: November 05, 2012, 12:48:43 pm
Just to close this thread I figured I should say that I did end up getting the Arduino WiFi shield.  Within 5 minutes I had the thing installed, talking to our enterprise access point and hosting a web server.  The difference in experience between these these two shields was night and day.
15  Using Arduino / Project Guidance / Re: 802.11g WiFi Shield on: October 23, 2012, 11:51:15 pm
So I think we are getting sidetracked a little from my main question.  Has anyone tested the Arduino WiFi shield with 802.11g only routers (without mixed-mode or 802.11b compatibility enabled)?
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