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andi38 / TPMS

Decode tire pressure monitoring system TPMS BLE 433MHz CC1101 ESP8266 ESP32
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Can't get it working #5

Open alejandroalis opened 2 days ago

alejandroalis commented 2 days ago

Hi!

I've tried running the example on an ESP32 with the 433MHz wheel sensors, but no luck. Communication with the CC1101 is working correctly; it initializes everything, but it doesn’t receive any data. I know the TPMS is sending data because I can read it correctly with the RTL-SDR, and thanks to the rtl_433 utility, I can see readings compatible with the ‘truck’ sensor type. I tried changing the sync bytes to other values based on the readings I had from the SDR, but still nothing. I noticed that when compiling the code, there was an error (a missing ; on line 81 and the setFlag function isn’t declared at the beginning), so I'm wondering if the code was really tested or if you made any changes. Any help would be appreciated!

unverbuggt commented 14 hours ago

Hi,

I'm currently working on reading tpms_ford.c devices and I've learned something yesterday: The TPMS sensors send using OOK modulation when triggered by the 250kHz trigger tool and they use FSK while the wheels are spinning. This is not a big problem for a SDR (Maybe it is possible for rtl_433 to show the used modulation?), but a big problem for the CC1101 chip. You can try adding radio.setOOK(true); in the setup routine. But best is to use Universal Radio Hacker with the SDR and record the signal and then check the modulation.

alejandroalis commented 10 hours ago

Hello unverbuggt! I’m using some from Aliexpress for a motorcycle; they only have a pressure sensor, and I noticed they detect when the vehicle moves by changes in the pressure, without an actual motion sensor—pretty clever. Using the RTL-SDR, I can capture the data, but no configuration works with the CC1101. I tried following your example and changing everything, but still nothing… did you ever manage to get it working?