2016-08-06 11:23 - Making
My new boards arrived and I've assembled the first (totally working!) "wi_ther" environmental sensor. The prototype, which I've posted about before, and was supposed to be the final version, is on the left while the new board is on the right.
The new board is larger, to put more space between the hot WiFi/controller chip and the three sensors, which are closer to the proper USB connector, rather than the on-PCB fingers. I got the connector a tiny bit wrong, I had to cut off a bit of the board to make it fit properly, since I put too much empty space around the holes for it to mount to.
You can see three internal cut out slots to help break any thermal transfer from the controller to the part of the board where the sensors are. The surface mount temperature sensor also has extra cutouts around it, and the two other sensors have big slots cut out beneath them, which is nearly invisible in this picture.
I'm still finalizing how I want the software to work. For now this system is running an HTTP server, which can be polled. I've also considered letting it run as an HTTP client, periodically pushing the data out. It might be nicest for it to run as an independent system, keeping a buffer of historical data in memory, in case anything causes my normal system to miss then that data can be retrieved thanks to the independent storage. But for now, it's time to stress test it and verify whether my thermal design for this version helps the sensors provide accurate data. (Early signs are good! In the few minutes it's taken me to type up this post, the reading has remained flat, so they haven't been heated by the processor!)