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1  Using Arduino / Networking, Protocols, and Devices / Wifi shield seems a bit buggy on: November 29, 2012, 09:08:33 pm
I'm using a Wifi shield ( on a weather station. I've noticed a problem.

As part of a test, I unplugged the power from the wireless router it was talking to. As expected, the Arduino application noticed a dropped TCP connection and started trying to reconnect. When that failed enough times, it used the watchdog timer to reboot the Arduino, on the grounds that it needed to reset everything to get a connection going again.

That worked fine, but after the reset, the Arduino diagnosed a missing Wifi shield. I'm guessing the watchdog reset did something bad to the shield, and it stopped responding.

The fix was to hike out and power cycle everything. That's not a great solution for a weather station in the middle of winter; people looking for a very high reliability, recover-from-anything wifi solution may need to consider other options.
2  Development / Other Software Development / WiFi class reports the same signal strength every time on: November 25, 2012, 09:32:56 am
As far as I can tell, the Wifi Shield measures the signal strength once, when it acquires the signal, and then reports that same value no matter when you ask for it. This means the shield can't be used as a signal strength meter, and you can't diagnose marginal connections by moving the shield and seeing what changes.

Being able to command remeasurements would be very nice to have.
3  Using Arduino / Project Guidance / Re: Weather station - design help requested on: October 27, 2012, 12:09:30 am
According to SparkFun, where I planned to buy stuff, the current Wifi shield doesn't work on a Leonardo because the Leonardo puts the relevant communications pins on a header that the shield doesn't use.

Yes, I absolutely want to use TCP over Wifi. I had a commercial weather station that used something closer to Xbee, and reliability was horrible. Data routinely got lost, even over the small (< 100') span. TCP will give me the retries and checksumming I need to get data reliably, and I already have a wireless network at the site, so I'd like to use it.

I want interrupts for the rain gauge and anenometer because polling for changes isn't much of an option, not when the processor will occasionally be busy with analog inputs and TCP and one wire stuff. Interrupts are a simple way to get the data regardless of what's going on, and allow simple debouncing of the inputs. I could use counter chips to keep count of the rain gauge and anonemeter events, but I don't know how I'd debounce the inputs going to the counters. It's easy in software.

I want one-wire for temperature and humidity because I already have one-wire devices for those things. Once I have the basic one-wire interface working, I can write the code to handle individual devices myself.

I was looking at offloading one-write to a one-wire controller chip (with a serial connection to the arduino) because the one-wire library I saw turned off interrupts for over 60 microseconds at a time, and I didn't know how well that would go over with TCP code. But if people have had no problem combining TCP and the one wire library, I'll happily dump the controller chip.

I want analog input for wind direction because I already have a sensor that reports direction with a varying resistance, so I can get varying voltage easily.

I have no immediate use for communicating back to the weather station, but since I'll be using TCP anyway and TCP is bidirectional, I'm sure I'll find uses for it eventually.

So I suppose my only remaining question is whether anyone's had problems doing TCP and One-wire in the same processor. If not, I can probably use an Uno and a Wifi shield and get everything I need. (Or a Leonardo if someone can convince me SparkFun has it wrong.)

4  Using Arduino / Project Guidance / Weather station - design help requested on: October 23, 2012, 06:25:30 pm
I'd like to use an Arduino to create a wifi weather station. Here's what I need:
Wifi (TCP) to send and receive data.
A one-wire interface to several weather devices.
2 interrupt lines, to handle signalling from other weather devices.
An analog input to handle yet another weather device.

I've hit a wall trying to design a solution. The TCP wifi is non-negotiable; which seems to limit me to a Uno or Mega, since the Wifi shield apparently does not work with anything else. I don't see a one-wire solution for Arduinos in general (why??), so I was expecting to to use a Peter Anderson chip that converts serial commands to one-wire signalling. But to use serial ports I have to give up debugging over USB (except on the Leonardo, but the Leonadro doesn't seem to have a wifi solution.)

Am I using the wrong processor? I didn't expect this to be complex.
5  Using Arduino / Project Guidance / Re: Wifi suggestions on: July 30, 2012, 07:43:45 pm
Ok, I probably wasn't clear. I need (or want) the weather station to connect directly to my existing wifi network access point. If I need a dedicated receiver, plus a PC where the receiver is, that's not the solution I'm looking for.
6  Using Arduino / Project Guidance / Wifi suggestions on: July 29, 2012, 01:51:40 pm
I'm considering using an Arduino uno for a weather station, and need wifi access for the Arduino, so I can do a TCP connection (I'd prefer not to use a web interface).

I see a few shields out there (CuHead being one), but what I'm not finding is code samples. I'd like to have some idea how complex the code is. The shields seem to have next to no documentation, so I'm looking for some reassurance that I'm not going end up implementing TCP on my own or something. Basically... what's simple to use?
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