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[on:]

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?

[Reply #1 on:]

Simple to use is an RN-XV (Roving networks) http://www.rovingnetworks.com/products/RN_XV. It simply has a serial connection which you can configure to be transparent to your application.

The drawback is a lack of flexibility. You don't have the same control over the connection(s) as you have with a product like the WiShield or the WiFi Bee.

[Reply #2 on:]

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.

[Reply #3 on:]

Ok, I probably wasn't clear. I need (or want) the weather station to connect directly to my existing wifi network access point.

Isn't that what the RN-XV module does?

[Reply #4 on:]

@OP: You're probably stuck because the RN-XV is in the XBee form factor. That does not mean it's a ZigBee network module. You get WiFi (as the RN-XV), GPS, Bluetooth, ZigBee and probably other modules in this form factor, it's not limited to one usage. It does connect to a WiFi network but it's configured and used through the serial interface. I use mine to gather moisture soil and temperature data which it sends directly to my server, over the network not by using another PC.

[Reply #5 on:]

@OP: You're probably stuck because the RN-XV is in the XBee form factor. That does not mean it's a ZigBee network module. You get WiFi (as the RN-XV), GPS, Bluetooth, ZigBee and probably other modules in this form factor, it's not limited to one usage. It does connect to a WiFi network but it's configured and used through the serial interface. I use mine to gather moisture soil and temperature data which it sends directly to my server, over the network not by using another PC.

When you say serial interface over WiFi, I'm not sure what you mean.  So like a Serial.println("hello"); would transmit "hello" over WiFi, but to where?  Using TCP/IP?

[Reply #6 on:]

When you say serial interface over WiFi, I'm not sure what you mean.  So like a Serial.println("hello"); would transmit "hello" over WiFi, but to where?  Using TCP/IP?

No.  It transmits it to the device connected to the serial pins.  In this case Serial.print() would send the commands to the WiFi device.

The WiFi device is designed to receive commands over Serial.

[Reply #7 on:]

James C4S is correct, the characters sent over the serial interface are usually commands for the device. One of these commands is telling the device to connect to some port on some host and then you get a connect message (if successful). After that you have an almost transparent connection to a server you can use more ore less like the serial connection to the PC you use for programming your Arduino.

If you program the RN-XV appropriately you can have a transparent connection without sending commands to the device. It then automatically connects to the configured server at the configured port at power-up. Server in this context just means a computer reachable for the Arduino over the network and running a program that is listening on that configured port.