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In this day and age, we should not need to use any keys or buttons. I have done away with the key remote in my car using this simple setup. I came to the same conclusion as this gentlemen in using the apple nike+ sensor to provide a proximity sensor to the car. 




His code lacks a couple things that I was looking for.

1) decoding of the apple serial protocol so that i can use any NRF module

2) detection of when to stop strobing the remote (when the key is inserted)

3) ability to open the trunk


and since I can detect when the key is inserted, I can do other things when the car is on like strobing the garage door opener, 


To accomplish 1, I found that some genius went about decoding the modules to be decoded with NRF modules




Also helping this along was energia and the already written NRF24 library. 


notes about my design and things I learned:


- my design is based all on a repeating 10ms timer which is a good base for modifying this code to work for different scenarios

- i am a fpga designer and some of the code is not as efficient as a c++ programmer would make it 

- one could optimize the interrupt routine to use less time by using a global counter and variables to store offsets rather than individual counters

- my mazda remote is active low so the signals had to be inverted

- i tapped into my car through the mazda  keyless module. 12v and gnd is provided. an additional signal which pullses low at a 1khz rate when there is no key inserted, it is high when a key is inserted, this powers "car timeout"

- i originally had everything on one board, but it seemed there was too much interference for the NRF to pick up the sensor properly 

- since there were a lot of rf devices decoupling capacitors was very necessary. 

- there is a 24 second timeout before my car relocks if there is no door opened, i kludged a single button press keep alive  every 20 seconds using delays :-( i dont like using delays they seems so unclean.... an upgrade would be to use the -64dbm to detect that you are actually in the car and stop the strobing, ymmv and i have not implemented this (RPD register 0x09 bit 0) UPDATE: IMPLEMENTED IN NEWEST CODE

- whenever the key is in the car, the car will cycle every ~2.5 seconds through the two parkade doors. the remote will auto shutdown if it detects a constant press so i have added a remote_pause to prevent this

- the trunk has another msp430 performing capsense on the key hole and will activate another nike+ sensor to open the trunk. i am in the process of upgrading the sensitivity of this using swept frequency capacitive touch which i will share once i get the kinks out 

- a cheap chinese buck module was used to reducethe voltage from 12v to 3.3v

- replace the *_sn vectors with whatever your nike+ sensor serial number is 

- avoid RF like the plague, even with one side guaranteed to be working, along with some issues with SPI, it was a PITA to get working the first time







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@@lalalandrus Good stuff. Does your car come with keyless entry?

Also, .ino files are now allowed.


Ok. I made a mistake. In the process of editing your post, I deleted the two source files. Could you please re-upload it. I'm unable to upload files from where I am right now. Keep them at .ino

I have a backup - just in case.

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