Custom USB tyre pressure monitoring interface - Page 43

wiggy · 07-14-2008, 01:27 PM

Have tryed both of these ..centrafuse and RRTMS Config out of the RR file

Also using TPMS DOCTOR to do a master reset..although sometimes it takes 2 or 3 goes to clear the pic !!

a__l · 07-15-2008, 01:47 AM

Quote: Originally Posted by Robby BMW;

The transistor has the dual function to invert the signal and bring it to 5V, as the output from the receiver is about 3.8V.

Robby, Thanks for the answer :-) In case of WAECO the output from the receiver is also about 3-4V but my micro controller (Atmel MEGA) recognizes 0 and 1 in the input. Does the PICs can't recognize 1 within 3.8V in the input? (I mean, might be I can put away this part from my realization).

Robby BMW · 07-16-2008, 12:37 PM

Quote: Originally Posted by wiggy

Have tryed both of these ..centrafuse and RRTMS Config out of the RR file

Also using TPMS DOCTOR to do a master reset..although sometimes it takes 2 or 3 goes to clear the pic !!

Ok, try this:
Do a master reset to the PIC with TPMS DOCTOR, then perform the learnig procedure trough RRTMS Config taking care to place the receiver at least 1 meter from the tyres and to wait at least 1minute between a tire and the other.

Robby BMW · 07-16-2008, 12:40 PM

Quote: Originally Posted by a__l

Robby, Thanks for the answer :-) In case of WAECO the output from the receiver is also about 3-4V but my micro controller (Atmel MEGA) recognizes 0 and 1 in the input. Does the PICs can't recognize 1 within 3.8V in the input? (I mean, might be I can put away this part from my realization).

Maybe, but for safety I put the transistor which also operates as a sort of Schmitt trigger.

a__l · 07-17-2008, 02:12 AM

Quote: Originally Posted by Robby BMW

Maybe, but for safety I put the transistor which also operates as a sort of Schmitt trigger.

For safety just to make sure that the voltage will not more that 5V (safe for PIC input)? Is it correct?

Robby BMW · 07-17-2008, 04:27 AM

Not exactly, since the receiver is powered by the same voltage of the PIC (5V), it is impossible to get an output level over 5V.

a__l · 07-17-2008, 10:16 AM

Quote: Originally Posted by Robby BMW

Not exactly, since the receiver is powered by the same voltage of the PIC (5V), it is impossible to get an output level over 5V.

Yes... agree :-) (my assumption was wrong) .... nevertheless what kind of "safety" did you mean?

(Managed to get data from WAECO system .... thanks for your answers)

Robby BMW · 07-19-2008, 10:15 AM

I should have had to say "just to be sure"... just to be sure to get a good signal.
My bad... in Italian "for safety" can also mean "just to be sure".

GizmoQ · 07-19-2008, 10:09 PM

Quote: Originally Posted by LYHTSPD

I do not have any of the 3rd Eye kits left, but I do have several of the USB converters left. They are complete with Robby's PIC, case, and USB cable. PM me if you are interested.

Thanks to LYHTSPD, RRFusion and RRTMS, I now have my fusion brain/TMS skin fully operational. Now I just need to buy and install the sensors and receiver.

goosey2099 · 07-19-2008, 10:39 PM

I'm having a littlebit of an issue here. It seems that if i place the receiver within that 1m from the tire then the RRTMS Config learns the sensor. But if i keep the receiver in the middle of the car I have no connection to any tire. This is really starting to drive me insane as it allmost looks like there is not enough power comming into the receiver. Also I have this plugged into a 8port usb hub and all 8 ports are being used for something. Can anyone shed some light on this issue?

mrbean_phillip · 07-20-2008, 02:59 AM

It seems your car is screening the signal to well - ie the RF can't penetrate.

Just to make sure, when you don't receive any updates, do you have the receiver external in the middle of the car, ie on the roof, or internal in the passenger cabin?

If the latter, you may need to mount an external antenna for the reciever.....

Keep us posted.

Robby BMW · 07-20-2008, 05:11 AM

You can build a simple 433.92 MHz antenna with a thin 50Ω coaxial cable as shown in this picture:

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a__l · 07-20-2008, 04:27 PM

Quote: Originally Posted by Robby BMW

I should have had to say "just to be sure"... just to be sure to get a good signal.
My bad... in Italian "for safety" can also mean "just to be sure".

Hi Robby.
Thanks. Would like to confirm that WAECO device is fully compatible(including CRC) with your investigation and realization (I used my own program and ATmel device but based on your research. The only thing is the rate for getting pressure. In my case the formula is a little bit different[pressure = 2.38*RAW data(from sensor) - 70 but to get BAR] but the idea is the same) :-) By the way have you thought also about displaying the signal strength coming from sensors?

Lok · 07-21-2008, 11:13 AM

I know many of you guys are having issues with signal strength. As I am working on the new model please offer me any suggestions/ideas you have to improve the signal. I wanted to move away from the Coil type antenna they have on the 3rd eye kit and possibly use something with a bit more reception. I can possibly just have a long wire hanging out similar to the wire Robby has pictured above but maybe something a bit more industrial/robust like the rigid antennas they use for routers and such might be a better option. Please provide links/pictures of any ideas...

goosey2099 · 07-21-2008, 12:25 PM

Robby, Do i have to unsolder the original antena or can i solder that peice directly onto the existing one? Also I used the doctor application yesterday and did a master reset. Now the doctor appllication is unable to see any changes in the tire presure.