my sensor will have a harsh life in this whale of a hot air balloon - temperatures up to 125°C and quite humid (ruuvi tag sits outside in a cooler environment) and when packing up the envelope there are quite some forces on the setup
so I thought the flat cable is not a realistic option and went for the Focusense sensor
just to convey the idea - mounting looks similar to this:
I guess I need to come in through the top of the case by drilling a hole and fastening the cable rigidly so it cant tear off that easily
one option would be a very short flat cable with some kind of breakout board to solder the TMP117 wires onto, all within the case above the PCB
btw the Focusense sensors are well built but the cable jacket material looks like it’s designed more for indoor applications - not particularly heat resistant. To use the TMP117 over its full temperature range a silicone or teflon cable would make sense.
I’ll cover the cable with a teflon hose just in case.
It turns out the humidity sensor in the breathable Ruuvi Pro in fact is very useful for balloon envelopes: if one packs up the envelope on wet ground and lets the bag sit during warm season for a few days there’s a good chance of mold developing which destroys the envelope for good. I think a humidity alarm from the tag will be super useful!
I got 2 and they seem to work mechanically ( for me I had to try a couple of times to line it up) Note that the ZIF receiver flips up as apposed to the ruuvi which slides out.
I haven’t connected anything to the board yet.
Based on picture, I think your board does not have TMP117 onboard. Latest production firmware 3.30.4 should work as-is on it.
Temperature sensor priority list is: TMP117, SHTC3, DPS310, BME280, nRF52, LIS2DH12. Other sensors will keep running to provide other sensor data. The broadcasted value comes from TMP117.
We made a special sensor comparison firmware which read every sensor separately and broadcasted the sensor values under unique MAC addresses, but it’s meant only for verifying sensor accuracy and does not suit any production use-case.
thanks - so that one should work out-of-the box if it detects the TMP117 - easy!
before I dig into the repo… is the PCB board temperature also reported from one of the other sensors? that’d be interesting given our peculiar mounting position
sure the humidity and pressure sensors report temperature as well, just a question if one of those makes it into the manufacturer data vector
yes, that particular image shows a non-Pro board.
What happens if we connect a TMP117 externally to a pro board? the external TMP117 sensor answers on I2C 0x49
hope this works, I’d love to get by with stock firmware
thanks!
Michael
ps: can I tack on a suggestion re the manufacturer data format:
instead of going through X versions of tagged C structs, why dont you switch to the self-describing protobuf format? it’s already in the SDK (nanopb) and great Finnish software btw!
that opens the route to arbitrary sensor data being tacked on and it would be backwards compatible, which your current method is not
Regrettably no, although creating a custom data format is relatively easy.
As of current firmware, external TMP117 will drain energy while not getting read by the firmware. We have detecting different I2C addresses on our roadmap, but I cannot make promises about the schedule. Line to be changed is here.
I’d love to, but BLE advertisements limit what we can do quite a lot. The communication is broadcast, many-to-one with no guarantees about data delivery and payload is at maximum 24 bytes. It’s not possible to pack as much information as we do into a more flexible format.
@Michael_Haberler Thats a very nice project. I have one for 4WD shock absorbers to implement. So will follow your lead with focusence. we have an office in China. How easy is it to make the firmware change you listed? What is battery life expectancy? Cheers and thanks again
software is the stock ruuvi repository, with a single change - modifying the I2C address of the sensor and recompiling - so for battery use, the rules for the stock software apply
all pretty straightforward - @vincentamon did this
I’ll see into having the repo published with instructions
for contacting Focusense, see the coordinates above - contact Mrs Melody Liu, she’ll be in the know
