[HOWTO] Debugging OBD Communication

Collection of all FAQs and HOW-TOs posted throughout the system. Read only.
froggy47
20 or more Posts ★★★
20 or more Posts ★★★
Posts: 129
Joined: Tue Feb 25, 2014 2:20 am

Re: [HOWTO] Debugging OBD Communication

Postby froggy47 » Mon Mar 09, 2015 5:44 pm

gplracerx wrote:I set my accelerometer update rate to 100Hz. It shows up as 91Hz on the accelerometer display. At 20Hz, the filter time constant is too low for autocross, in my opinion. YMMV. If I get time, I'll put up some graphs to show the effect. I've got to prep the car for the Dixie National Tour event this weekend.


I would really like to see those, thanks you if you can post.

:)


Autox & HPDE
2004 Corvette Z06
Moto X/android, Dual 160, generic OBD2
froggy47
20 or more Posts ★★★
20 or more Posts ★★★
Posts: 129
Joined: Tue Feb 25, 2014 2:20 am

Re: [HOWTO] Debugging OBD Communication

Postby froggy47 » Mon Mar 09, 2015 5:47 pm

Is there any downside to going higher than 30 Hz?

:)


Autox & HPDE
2004 Corvette Z06
Moto X/android, Dual 160, generic OBD2
User avatar
Harry
Site Admin
Site Admin
Posts: 8069
Joined: Sun Sep 12, 2010 10:32 am
Location: Cologne, Germany
Has thanked: 93 times
Been thanked: 338 times
Contact:

Re: [HOWTO] Debugging OBD Communication

Postby Harry » Mon Mar 09, 2015 6:09 pm

Yes, processing load / battery drain. 30 Hz is good for GPS update rates of 10 Hz and below. Some prefer higher resolution to get less smoothing, but for most, 30 Hz is fine.

- Harry


Image Image Image Image
froggy47
20 or more Posts ★★★
20 or more Posts ★★★
Posts: 129
Joined: Tue Feb 25, 2014 2:20 am

Re: [HOWTO] Debugging OBD Communication

Postby froggy47 » Mon Mar 09, 2015 8:53 pm

Harry wrote:Yes, processing load / battery drain. 30 Hz is good for GPS update rates of 10 Hz and below. Some prefer higher resolution to get less smoothing, but for most, 30 Hz is fine.

- Harry


Thanks Harry!

I just realized there are (in expert settings):

Accelerator tweaks update rate (mine is now 30)

AND

Sensor Delays (also in expert settings):

GPS 1.5
OBD 1.0
Accelerator 0.5

Those I believe are the default sensor delays, are they OK?

:)


Autox & HPDE
2004 Corvette Z06
Moto X/android, Dual 160, generic OBD2
User avatar
Harry
Site Admin
Site Admin
Posts: 8069
Joined: Sun Sep 12, 2010 10:32 am
Location: Cologne, Germany
Has thanked: 93 times
Been thanked: 338 times
Contact:

Re: [HOWTO] Debugging OBD Communication

Postby Harry » Mon Mar 09, 2015 9:16 pm

Yes, these are the default. Please don't change them. Video Synchronization / Video should be 1.0.

- Harry

P.S. None of these are related to OBD communication.


Image Image Image Image
froggy47
20 or more Posts ★★★
20 or more Posts ★★★
Posts: 129
Joined: Tue Feb 25, 2014 2:20 am

Re: [HOWTO] Debugging OBD Communication

Postby froggy47 » Tue Mar 10, 2015 4:20 am

Harry wrote:Yes, these are the default. Please don't change them. Video Synchronization / Video should be 1.0.

- Harry

P.S. None of these are related to OBD communication.



Overlay Synchronization

Video 0.0-9.0s
This preference's current value: "0.5"

I HAVE NEVER TOUCHED THIS.

:)


Autox & HPDE
2004 Corvette Z06
Moto X/android, Dual 160, generic OBD2
User avatar
Harry
Site Admin
Site Admin
Posts: 8069
Joined: Sun Sep 12, 2010 10:32 am
Location: Cologne, Germany
Has thanked: 93 times
Been thanked: 338 times
Contact:

Re: [HOWTO] Debugging OBD Communication

Postby Harry » Tue Mar 10, 2015 8:06 am

Yes, sure :-D


Image Image Image Image
gplracerx
20 or more Posts ★★★
20 or more Posts ★★★
Posts: 803
Joined: Thu May 03, 2012 5:26 am
Location: Kingsport, TN USA
Has thanked: 11 times
Been thanked: 29 times

Re: [HOWTO] Debugging OBD Communication

Postby gplracerx » Tue Mar 10, 2015 3:58 pm

30Hz is fine for track use. In autocross, the time constants for direction changes are much shorter than on a race track and need a correspondingly smaller time constant filter. The filter time constant is proportional to the sampling time constant. A higher sampling rate gives a smaller time constant.


froggy47
20 or more Posts ★★★
20 or more Posts ★★★
Posts: 129
Joined: Tue Feb 25, 2014 2:20 am

Re: [HOWTO] Debugging OBD Communication

Postby froggy47 » Tue Mar 10, 2015 5:36 pm

gplracerx wrote:30Hz is fine for track use. In autocross, the time constants for direction changes are much shorter than on a race track and need a correspondingly smaller time constant filter. The filter time constant is proportional to the sampling time constant. A higher sampling rate gives a smaller time constant.


Trying 100.

:)


Autox & HPDE
2004 Corvette Z06
Moto X/android, Dual 160, generic OBD2
froggy47
20 or more Posts ★★★
20 or more Posts ★★★
Posts: 129
Joined: Tue Feb 25, 2014 2:20 am

Re: [HOWTO] Debugging OBD Communication

Postby froggy47 » Tue Mar 10, 2015 5:38 pm

Harry wrote:Yes, sure :-D


Haha, really I never touched it, should it be 1.0? I don't even know what it does.

:)


Autox & HPDE
2004 Corvette Z06
Moto X/android, Dual 160, generic OBD2

Return to “FAQs and HOW-TOs”

Who is online

Users browsing this forum: No registered users and 1 guest