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Discussion Starter · #1 ·
I made a thing:


Requirements:
  • MZD-AIO
  • custom TPMS app
  • executable file for the communication protocol with the:
  • Arduino microprocessor with receiver (USA: 315 MHz; Europe/Rest of the World: 433 MHz) on one of the USB-ports
  • 315/433 MHz OEM tire pressure sensors (the ones that Abarth uses OEM)

It's still a beta version; Despite saying it saved the order of the IDs, it didn't really. But that's what I'm figuring out next (for now, there's a trick to save the sensors' IDs to fix them to a position, though).

Next steps:
  • saving positions
  • configuration setup for different setpoints, warning ranges, car models/colors
  • translations (and using °F and PSI)
  • making an installer analog to Speedometer-App
  • publishing the PCB layout or maybe even get a small series of processor/receiver units to sell (I'm looking for deals atm).
  • some design updates for the app
 

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This is very cool and relevant to my OCD car needs
 

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2017 Fiat 124 ABARTH
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1,241 Posts
Very impressive work! Look forward to when you release it!
 
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I made a thing:


Requirements:
  • MZD-AIO
  • custom TPMS app
  • executable file for the communication protocol with the:
  • Arduino microprocessor with receiver (USA: 315 MHz; Europe/Rest of the World: 433 MHz) on one of the USB-ports
  • 315/433 MHz OEM tire pressure sensors (the ones that Abarth uses OEM)

It's still a beta version; Despite saying it saved the order of the IDs, it didn't really. But that's what I'm figuring out next (for now, there's a trick to save the sensors' IDs to fix them to a position, though).

Next steps:
  • saving positions
  • configuration setup for different setpoints, warning ranges, car models/colors
  • translations (and using °F and PSI)
  • making an installer analog to Speedometer-App
  • publishing the PCB layout or maybe even get a small series of processor/receiver units to sell (I'm looking for deals atm).
  • some design updates for the app
Torben! Great work! Not sure you'll recognise my screenname, but this should help jog your memory haha

85840


I might be able to help you with the PCB work. I have a Voltera V-One and plenty of 3D printers so can help validate prototypes / do a small batch if thats the stage you are at. Drop me a message on FB if I can be of help. I was wondering is it possible to buy some off the shelf TPMS sensors for my second set of wheels with the track tyres on and configure the receiver easily?

I was looking into doing custom apps through Android Auto but it looks very restricted and deliberately undocumented by Google. Not sure if you have heard of anything on this front?
 

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2017 Fiat 124 Spider Abarth, fully loaded from the factory, with just a wee bit of aftermarket mods.
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Looks great, and something I miss from my 500 Abarth. Based on what you're showing it seems you know how the TPMS are broadcasting.

The topside view of the vehicle with the temp and pressure showing for each wheel location is excellent, as well as the secondary screens with the detailed sensor info.

A bit off on a tangent, but, as you progress with your design, could I be so forward as to ask for a couple of design considerations? I know you said you're working on incorporating the imperial units as a display option.... but could this be a setting for both pressure and temp separately? I think of temps in Celcius, but still read tire pressure in psi, no bars. The other thought that came to mind is as you try to figure out how to lock down the location of each sensor that's being read, but how would that be affected when a tire rotation is performed?

Absolutely love what you've accomplished so far. It looks incredible!

@ameridan , pretty slick, right?
 
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Discussion Starter · #7 ·
Torben! Great work! Not sure you'll recognise my screenname, but this should help jog your memory haha
Of course I remember, though the photo helped my memory! What an awesome weekend at the Nürburgring. I'll be there next week.
I'll contact you on fb, when I'm back, let's see what we can make happen!

Looks great, and something I miss from my 500 Abarth. Based on what you're showing it seems you know how the TPMS are broadcasting.
Yes, that was an interesting project in itself. I worked with RTL-SDR on a Raspberry Pi to catch the sensor signals, which I knew were 433 MHz (for me in Europe). Once I received the binary, I had to decode it, though. This (merbanan/rtl_433) helped and I added my findings (merbanan/rtl_433).

The topside view of the vehicle with the temp and pressure showing for each wheel location is excellent, as well as the secondary screens with the detailed sensor info.
Thank you, I'm really happy how it turned out. It'll be a bit of a headache though, to add color variants, MX-5, Mazda 3, and so on. ;)

A bit off on a tangent, but, as you progress with your design, could I be so forward as to ask for a couple of design considerations? I know you said you're working on incorporating the imperial units as a display option.... but could this be a setting for both pressure and temp separately? I think of temps in Celcius, but still read tire pressure in psi, no bars.
Yes, Celsius + PSI is absolutely possible. @chilicharger665 ;)

The other thought that came to mind is as you try to figure out how to lock down the location of each sensor that's being read, but how would that be affected when a tire rotation is performed?
The microprocessor weights the signal it receives. Imagine you're at an event with several other 124 Spiders or MX-5s: The receiver might get signals from the next car. But it checks how often each sensor is read and how "trustworthy" each sensor is. The first four from the sensors list then get send to the other side of the protocol on the CMU.
But the CMU side can also send a configuration to the microprocessor, telling it which sensors to put in what place.

So initially, you'll receive four signals without knowing where they come from. My suggestion is: Go around your car, release tire pressure, for example: FL 28 psi, FR 29 psi, RL 30 psi, RR 31 psi.
Then wait for the app to show the signals (you might have to drive a little bit so the sensors get woken up), go to the settings and select the sensors according to the tire pressures.
When you rotate your tires from front to rear and rear to front, just push the button "Rotate" in the settings and it'll switch these positions.
Saving will then tell the CMU side protokol executable to send a new configuration to the microprocessor, which will then save it and know the order in which to send the four signals.

The output from the processor:
0: 0f5476ea 26.0 1.99 1: 0f547711 26.0 1.96 2: 0f54771b 24.0 1.96 3: 0f547e8 24.0 1.97

The app's work:
0: 0f5476ea 26.0 1.99=> Front Left 26°C 1.99 bar
1: 0f547711 26.0 1.96=> Front Right 26°C 1.96 bar
2: 0f54771b 24.0 1.96=> Rear Left 24°C 1.96 bar
3: 0f547e8 24.0 1.97=> Rear Right 24°C 1.97 bar

Let me know if you have further question, suggestions, ideas. I'm really happy to find someone interested and giving some feedback/input/ideas.
 

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2018 124 Spider Abarth Custom
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Of course I remember, though the photo helped my memory! What an awesome weekend at the Nürburgring. I'll be there next week.
I'll contact you on fb, when I'm back, let's see what we can make happen!



Yes, that was an interesting project in itself. I worked with RTL-SDR on a Raspberry Pi to catch the sensor signals, which I knew were 433 MHz (for me in Europe). Once I received the binary, I had to decode it, though. This (merbanan/rtl_433) helped and I added my findings (merbanan/rtl_433).



Thank you, I'm really happy how it turned out. It'll be a bit of a headache though, to add color variants, MX-5, Mazda 3, and so on. ;)



Yes, Celsius + PSI is absolutely possible. @chilicharger665 ;)



The microprocessor weights the signal it receives. Imagine you're at an event with several other 124 Spiders or MX-5s: The receiver might get signals from the next car. But it checks how often each sensor is read and how "trustworthy" each sensor is. The first four from the sensors list then get send to the other side of the protocol on the CMU.
But the CMU side can also send a configuration to the microprocessor, telling it which sensors to put in what place.

So initially, you'll receive four signals without knowing where they come from. My suggestion is: Go around your car, release tire pressure, for example: FL 28 psi, FR 29 psi, RL 30 psi, RR 31 psi.
Then wait for the app to show the signals (you might have to drive a little bit so the sensors get woken up), go to the settings and select the sensors according to the tire pressures.
When you rotate your tires from front to rear and rear to front, just push the button "Rotate" in the settings and it'll switch these positions.
Saving will then tell the CMU side protokol executable to send a new configuration to the microprocessor, which will then save it and know the order in which to send the four signals.

The output from the processor:
0: 0f5476ea 26.0 1.99 1: 0f547711 26.0 1.96 2: 0f54771b 24.0 1.96 3: 0f547e8 24.0 1.97

The app's work:
0: 0f5476ea 26.0 1.99=> Front Left 26°C 1.99 bar
1: 0f547711 26.0 1.96=> Front Right 26°C 1.96 bar
2: 0f54771b 24.0 1.96=> Rear Left 24°C 1.96 bar
3: 0f547e8 24.0 1.97=> Rear Right 24°C 1.97 bar

Let me know if you have further question, suggestions, ideas. I'm really happy to find someone interested and giving some feedback/input/ideas.
The Suzuki XL7 I had in 2008 had the system set up something like this. After rotation, you put the car in TPMS "learn" mode thru the dash app, horn honked 2 times. Starting at the Front Left, you lowered the pressure until the horn honked and moved around clockwise until finished. Horn honks 2 times again and done. Top off to whatever pressure you need.
 

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This makes me happy in the pants....

Curious though; it sounds like you are using an Arduino to read the sensors, and then pass the data into the CMU, correct? Do you mind if I ask how you are interfacing with the CMU?

I'm by far not an expert with Arduino, but I've dabbled with them quite a bit and have a (very small) background with C++. I'd be happy to help with any dev if/when possible. That said, I completely understand if you want to keep your code proprietary. In that instance, would it be possible to buy an Atmel processor, have you flash it, and then send it to me to plug in to an Arduino? I have an unused Mega sitting around, but I presume the standard Arduino has enough I/O to accomplish this?

Whatever the case, fantastic work, and can't wait to see more!
 

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2017 Fiat 124 Spider Abarth, fully loaded from the factory, with just a wee bit of aftermarket mods.
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Any updates on this?
Many of us had very high hopes for this, but his last post on this thread from well over a year ago appears to have been his last. Radio silence since then, and if you check their profile, you'll see no recorded activity in the forum since then either.
 
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