Other Parts Discussed in Thread: CC1310
I have previously developed a CC1101 repeater product for a different TPMS system that used a more traditional long preamble and high/low sync word. I am developing a different TPMS product for Schrader TPMS systems. Documentation I have for Schrader TPMS looks like this:
Packet payload: 1 sync nibble and 8 bytes data, 17 nibbles:
0 12 34 56 78 9A BC DE F0
7 f6 70 3a 38 b2 00 49 49
S PF FI II II II PP TT CC
- S: sync
- P: preamble (0xf)
- F: flags
- I: id (28 bit)
- P: pressure from 0 bar to 6.375 bar, resolution of 25 mbar/hectopascal per bit
- T: temperature from -50 C to 205 C (1 bit = 1 temperature count 1 C)
- C: CRC8 from nibble 1 to E
I tested and confirmed my results using Radio Hacker and another open source 433_rtl TPMS software.
Raw capture:
faab4aaaaab4acd2aad5534aaaccb4b52b4
Manchester Decode:
01ffe74fc09fd6638
spffiiiiiiippttcc
sync = 0x0
preamble = 0x1
flags = 0xFF
id = 0xe74fc09
pressure = 0xfd
temperature = 0x66
CRC8 = 0x38
My question is does TI have any hardware that can handle that short of a preamble/sync? CC1101 would be preferred but it requires a much larger sync word. Is there a way to get around that? I also have a CC1310 development board but SmartRF only lets me go down to 8 bits for sync. Is there another RF board I should look into?
