I recently is studying tire pressure monitoring system(TPMS) base on the FXTH870911DT1.
I use the MC33696 evaluation board and MC9S08RG60 demo board as the receiver.
I have now realized the communication between the FXTH870911DT1 and the MC33696,but there is a problem,A detailed description is as follows
As the transmitter,FXTH87 configuration information is as follows
1.Mode:FSK
2.Frequency:433.92MHz
3.Band rate:4800
4.Frame format:Praemble + ID + Header + data + EOM
0B1111 + 0B110101 + 0B100001 + 0B00001111 + EOM(RFCR2_EOM = 1)
RF Buffer:0xFD,0x61,0x0F
TPMS_RF_SET_TX(23);
As the receiver,MC33696 configuration information is as follows
1.Mode:FSK
2.Frequency:433.92MHz
3.Band rate:4800
4.DME:1
5.ID:F5
6.Header:E1
I receive the data by the Hyperterminal(MC33696 evaluation board + MC9S08RG60 demo board),now I can receive the 0B00001111(0x0F),the data is correct,
but I receive the 0B0000111111111111 (0x0FFF)randomly.
I try to change the data,RF Buffer:0xFD,0x61,0xF0,I receive the all data is 0B1111000011111111(0xF0FF) or 0B1111000001111111(0xF07F)
Then I clear the RFCR2_EOM,but all of the phenomenon is the same as described above.
I don't know why I receive the 0xFF and 0x7F eatra?
Can anyone help me.Thanks.
Hello Li,
Could you please test one of the example projects that can be found in the FXTH87 site please (especially the periodic RF transmission)? This will discard a potential error in the TPMS configuration.
Best regards,
Earl.