Open fresh4 opened 4 days ago
The later signals look like TPMS, 50µs PCM (MC) is common.
I.e. this will work to get raw data: -X 'n=name,m=FSK_PCM,s=52,l=52,r=150,bits>=60'
Your examples have raw data of 5555555695696A99556695966566955566A55969A666
which MC decoded is fffe 7985 fa76 ba7f a3d9 2a
or the inverse 0001 867a 0589 4580 5c26 d5
(which starts with the ID you have).
Try to find more raw codes and create a BitBench like this.
@zuckschwerdt you'll have to forgive me as signal processing is not my wheelhouse. I will try to collect more samples and see what I can do. How do you come up with the flex decoder that you're using? I've read the documentation but of course being pretty unfamiliar I'm not sure what each thing (l,s,y, etc) means exactly.
As an aside, I'm pretty sure (most?) TPMS signals use a 32 bit ID (after the preamble, I guess). There's a chance that the ID I provided was actually for a different tire on the same car, so 867a0589 might be the real ID. I will check when I'm able to get more samples.
It's just the minimum of options to get a working flex decoder: modulation (m) FSK with PCM slicer, short and long symbol (s, l) are the same "half-bit" length of 52 µs, and since we must never see any gap or pulse of more that two identical bits in Manchester coding the reset (r) of slightly longer that 2x 52 (and then demanding some minimum number of bits).
I've been testing TPMS RX via rtl_433 and an RTL SDR and have been able to detect most tested sensors except for one belonging to a 2023 KIA EV6. I was able to capture information with -A, and I did test the disabled by default -R decoders. Specifically, -R 123 returned an incorrectly decoded output. I'm fairly novice to rtl_433, so let me know if there's anything else I need to include or if I did something wrong.
Here is the analyzer output for the captured signal with this command: \
rtl_433 -R 123 -r g005_433.92M_250k.cu8 -C customary -A
THE ACTUAL DATA for this signal based on the TPMS sensor I used (as opposed to what the 123 decoder gives) is\ ID: 8679EDB4\ PSI: 34.5\ Temperature: 91F
Hopefully that helps with decoding; I'm not so sure how to do so myself.