Creating records from solarpanel boiler controller

Hello, I have quite a problem here. The goal is to log data from a solar panel controller which is connected to a water boiler. My father came up with the idea because the controller has 2 options of interfaceing with it. One is a RJ-Jack, I couldn't find out which it is in detail, the manual doesn't say much about what type of nor if it is the standard pin usage. The second one is a bit more interesting, they offer 2 female pin headers inside the controller to get data from. They don't really describe what the protocol, I believe it's mainly because they sell their products for the bus(es), but don't really care about things like "OpenSource". But wait, that's not the only problem. Another is how to save and transfer data. Of course, writing the whole data to a SD-Card would be the first thing to come in mind, but this solution wouldn't really be very user-friendly. The user would have to take every time he wants to know what is written in the logs the card out, which may not be too vital for the file-system while arduino is writing. Also, the time would need to be reset after every check for the logs. So I thought about using the WiShield. Well, WiShield uses some of the same pins as the SD-Card Module, so having both on the arduino which would be a pretty good idea is unfortunately not possible. :( Using the WiShield alone and transmitting all the data to an other computer which logs it then may be a solution, but actually not a good one. When the computer is being turned off arduino would have no place to log its data. A computer which would be 24/7 on would not only cost money but would also need electricity which would question the whole point of having solar panels for hot water and electricity from the first place. So, does anyone have a better solution for the [u]second[/u] problem which he or she would like to share?

(Note: I'll inform myself better about the whole interface of the controller later. Maybe a useful hint: The manufacturer of the controller, claims in the manual the RJ Jack uses RS232. No clue how.)

Sorry about the long text and the bad english in some phrases. :P


I bet you can count the number of people that can get openlog to work right without some serious amounts of fiddling on one hand

(here is 6 pages worth of mostly unanswered questions about THAT little demon)

As far as using the sd card and the wi shield together, well sd cards are pretty easy to interface, so you can move it to some free pins and not have to use the shield

as far as your rj jack, its just a jack, there could be anything wired to it, if the manual says rs232 then it probably is, you need to check its voltages and get a rs232 <> ttl serial level shifter