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toolic
toolic
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I am capturing the TPMS sensor transmitiontransmission in URH, but i am having extremely hard time to decode correctly the signal. I

I know exactly what is the data string that my real sensor is transmitting and i also know from the supplier that the sensor uses an Infineon SP37T chip, which transmits up to 10kbit/s. The supplier said they use FSK modultationmodulation, but looking the signal seems some phase shifting too. This is the string my sensor sends (in Hex): 54

54 50 56 2C A7 00 2C 00 0F 2C 00 66 2C 00 20 2C 00 00 2C 00 45 2C 00 FF 2C 00 51 0D 0A 00 0F 00 66 00 20 is the sensor ID. 45 is the temperature and 51 is CRC. I

I cannot decode right in URH, probably the many parameters on decoding are not correct.   

HERE are some samples i recorded with URH. The string transmitted is the same, but they look slightly different because i was trying different gains, antennas, sample rate and also tried with HackRF and RTL-SDR. I have noticed that the sensor sends 2 different blocks of data, not sure exactly why. For sure it is not a repetition. First may be a preamble(?). Appreciate if someone helps to make the decoding match the known data. Thanks!

I am capturing the TPMS sensor transmition in URH, but i am having extremely hard time to decode correctly the signal. I know exactly what is the data string that my real sensor is transmitting and i also know from the supplier that the sensor uses an Infineon SP37T chip, which transmits up to 10kbit/s. The supplier said they use FSK modultation, but looking the signal seems some phase shifting too. This is the string my sensor sends (in Hex): 54 50 56 2C A7 00 2C 00 0F 2C 00 66 2C 00 20 2C 00 00 2C 00 45 2C 00 FF 2C 00 51 0D 0A 00 0F 00 66 00 20 is the sensor ID. 45 is the temperature and 51 is CRC. I cannot decode right in URH, probably the many parameters on decoding are not correct.  HERE are some samples i recorded with URH. The string transmitted is the same, but they look slightly different because i was trying different gains, antennas, sample rate and also tried with HackRF and RTL-SDR. I have noticed that the sensor sends 2 different blocks of data, not sure exactly why. For sure it is not a repetition. First may be a preamble(?). Appreciate if someone helps to make the decoding match the known data. Thanks!

I am capturing the TPMS sensor transmission in URH, but i am having extremely hard time to decode correctly the signal.

I know exactly what is the data string that my real sensor is transmitting and i also know from the supplier that the sensor uses an Infineon SP37T chip, which transmits up to 10kbit/s. The supplier said they use FSK modulation, but looking the signal seems some phase shifting too. This is the string my sensor sends (in Hex):

54 50 56 2C A7 00 2C 00 0F 2C 00 66 2C 00 20 2C 00 00 2C 00 45 2C 00 FF 2C 00 51 0D 0A 00 0F 00 66 00 20 is the sensor ID. 45 is the temperature and 51 is CRC.

I cannot decode right in URH, probably the many parameters on decoding are not correct. 

HERE are some samples i recorded with URH. The string transmitted is the same, but they look slightly different because i was trying different gains, antennas, sample rate and also tried with HackRF and RTL-SDR. I have noticed that the sensor sends 2 different blocks of data, not sure exactly why. For sure it is not a repetition. First may be a preamble(?). Appreciate if someone helps to make the decoding match the known data.

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Pedro Silva
Pedro Silva
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How to decode TPMS FSK signal on Universal Radio Hacker

I am capturing the TPMS sensor transmition in URH, but i am having extremely hard time to decode correctly the signal. I know exactly what is the data string that my real sensor is transmitting and i also know from the supplier that the sensor uses an Infineon SP37T chip, which transmits up to 10kbit/s. The supplier said they use FSK modultation, but looking the signal seems some phase shifting too. This is the string my sensor sends (in Hex): 54 50 56 2C A7 00 2C 00 0F 2C 00 66 2C 00 20 2C 00 00 2C 00 45 2C 00 FF 2C 00 51 0D 0A 00 0F 00 66 00 20 is the sensor ID. 45 is the temperature and 51 is CRC. I cannot decode right in URH, probably the many parameters on decoding are not correct. HERE are some samples i recorded with URH. The string transmitted is the same, but they look slightly different because i was trying different gains, antennas, sample rate and also tried with HackRF and RTL-SDR. I have noticed that the sensor sends 2 different blocks of data, not sure exactly why. For sure it is not a repetition. First may be a preamble(?). Appreciate if someone helps to make the decoding match the known data. Thanks!