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Internet of Things - development log

We are getting slowly closer to a working prototype of an Arduino -> WRT54GL FunkFeuer node -> Pachube data connection. One idea is to use it to measure certain water properties, whether they are wave height, water level, water quality or something completely different.
We have followed Christian Haas' Leipzig Firmware guide from the Linz Funkfeuer wiki, and have had some students try it out and be successful too. So we now have two WRT boards as nodes. We have soldered on the pin header into the WRT, completely voiding any warranty that we might have had.
Right now we have made up a small connection for the Arduino, but we cannot run it from the 3.3 V on the header, even though we are using the Seeduino mega because it can run at 3.3V to match the internal voltage of the WRT. It actually needs more, which it then pulls down to 3.3V using some kind of voltage controller chip. So we will try that too. This ends up working.
Midnight update: the Kamikate OpenWRT serial interface /dev/cua/1 actually runs at 9600 baud. Which I had obviously not tested properly before.
So now we have a Seeduino sending data (test data) to the WRT, now we just need a very simple serial -> pachube connection in the WRT (python does not exist in there, perhaps LUI)
Morning update: We now have arduino data getting into a lua script and being interpreted. Unfortunately there are no explicit lua-> pachube examples we can find, although a few people are using them. So we are looking at the possibility of cheating using a wget hack from the WRT - by pretending to download a URL, it actually uploads data to the server. Curl will not fit on the WRT!
Afternoon update: there is a wget hack possible with normal wget, to be found on the Pahube community website. Unfortunately the wget implemented on the WRT is not the full wget! So this will not work. In the meantime caog, one of the pachube community members, has answered my request for some information, so we were able to use his code to get a lua script sending data to pachube. Because we are on a very unstable internet connection (it seems to come and go a lot!) we have had to add a few tests to make it work even when the connection is too wobbly.
Next steps (outside the hackathon) will include making the system work with a standard arduino, getting some interesting weather sensors attached to the arduino and getting one of the boards installed on a FF node with the appropriate autostart things installed.
And get some photos on this page!