Trouble with Implementing Gadgeteer Devices

Oct 21, 2013 at 3:05 PM
Edited Oct 21, 2013 at 3:10 PM

3 classmates and myself are currently attempting to implement a main project broken down into 4 components consisting of :
  • GHI Fez Hydra acting as a "Smart Picture Frame" , essentially acting as a picture frame with the capability to show the user upcoming tasks, weather information, display pictures, and set an alarm. Modules included are a SD Storage module for storing pictures to cycle through, RN171 WiFi module for connectivity, Tunes module for alarm audio functionality, and a T43 display module for the displaying of all aforementioned features.
  • GHI Spider acting as a security system, utilizing a motion sensor and camera to take pictures and send them to the Lab of Things hub for storing and viewing. Modules included are USB host module for temporarily storing any pictures taken before sending them via Ethernet to the Lab of Things hub, Serial Camera for taking pictures, PIR module for detecting motion, J11D Ethernet module for the transmission of pictures taken with the serial camera to the Lab of Things hub.
  • A Windows 8 tablet/laptop that can alter the various settings of the system including the size of pictures taken, arming and disarming the motion sensor, and other settings.
  • Lab of Things hub which allows them to speak with each other.
We are having a bit of trouble with the Gadgeteer side of things given that the examples bundled with Lab of Things include components that we do not have, namely, the RS21 WiFi module. The only WiFi module we have access to is the RN171 which seems to fulfill a different niche than the RS21 and is thus not completely applicable to what the documentation requires. As such, we have been attempting to alter the example code to fit our needs but are running into issues with the codes complexity and difficulty in understanding a lot of what we are given within the documentation.

Any and all help would be greatly appreciated.
Oct 22, 2013 at 9:35 AM

Thanks for posting! There are quite a few Gadgeteer-compatible networking modules, and they offer different capabilities so they are not necessarily drop-in replacements for one another

The Ethernet J11D module should be easier to swap in for the WiFi RS21 module as both modules use the NETMF TCP/IP stack. But, you do not need all the implemented functionality to do with discovering and joining a wifi network, since the Ethernet is already joined to a network. If you take the HomeOSGadgeteerDevice library, remove all the calls that relate to WiFi specifically and to discovering and joining the home network, and pin "ConnectedToHomeNetwork" to "true", then hopefully you should be able to get going.

I have not used the RN171 module before, but according to GHI's website it is a WiFi access point module, but it does not use NETMF's TCP/IP stack since it has its own built-in stack. The key thing you need to be able to take from the HomeOSGadgeteerDevice library is the part that sends UDP broadcasts to HomeOS. This allows the Gadgeteer scout on HomeOS to sense the Gadgeteer device. If you can make the RN171 listen to UDP traffic on port DiscoveryPort and whenever it sees any traffic there, send UDP broadcasts of the form specified in the IdentifierString property back to the sender on port DiscoveryResponsePort, then HomeOS should discover the device.

I hope this helps you port the library to your hardware.