Hi all,
Thanks to the awesome help on this forum I have a working hacked fridge running from a raspberry pi and arduino. It works very well! However, there are two glitches which may be related, one which is a real problem.
minor glitch - the beer temperature sensor (rarely other ones, but it happens) gets random rapid spikes in temperature which clearly are not happening in the wort. See the image. This is minor because while the brewpi tries to fix it by cooling, it settles down quick enough not to make a real issue in the beer.
The image shows some oddity with the fridge sensor as well but usually its just the beer.
This one baffles me. The one-wire bus is digital, so interference on the wire would mean a corrupted packet overall and not a predictably increased-temperature. Interference (if that is what it is) must be at the analog end of the IC. Bad memory at the arduino side (it's a knock-off) wouldn't be so regular and would more likely be all over the map.
major glitch - about once a week the arduino stops sending temp data!!! On the brewpi side of things, the site stays up and keeps logging, but I get COMPLETE blank space instead of temp data. The LCD readout gives me hyphens for the actual beer, room, and fridge temps.
The logs give me:
Dec 10 2015 21:32:43 controller debug message: WARNING 2: Temperature sensor disconnected pin 18, address 283379DC060000F6
Dec 10 2015 21:32:43 controller debug message: WARNING 2: Temperature sensor disconnected pin 18, address 288693DD060000F2
Dec 10 2015 21:32:43 controller debug message: WARNING 2: Temperature sensor disconnected pin 18, address 2855A53A060000B8
If I peek at the device (using cat...) I get:
L:["Mode Beer Profile ","Beer --.- 4.1 ▒C","Fridge --.- 1.0 ▒C","Idling for 03m27"]
Which shows that the arduino is still running, but it has decided not to give me temp data.
I can fix everything by unplugging the arduino and plugging it in again. Then it comes back up without having to touch the rpi side of things. Another oddity: when it comes back up, the "fridge" temp sensor reads a very high temp which comes down over a minute or two.
Any thoughts? How can I debug this? Thank you for any help you can offer!!