BlueWave Studio forum
obd lag/delay - Printable Version

+- BlueWave Studio forum (https://bluewavestudio.io/community)
+-- Forum: OpenAuto Pro (https://bluewavestudio.io/community/forum-86.html)
+--- Forum: OBD-II (https://bluewavestudio.io/community/forum-103.html)
+--- Thread: obd lag/delay (/thread-1932.html)



obd lag/delay - skrimo - 08-24-2020

Not really sure what could be the problem, but anything displayed on the OAP dash is delayed for approximately 1 seconds, or better say it has 1fps.

I use "Viecar 4.0 Bluetooth OBD2" adapter, and it works perfectly with my computer and my android phone, without any lag or delay.

rpi4/2gb, official 7" touchscreen, csr based Bluetooth adapter,...

----------------

I found this on the internet from someone who was building bmw dash with raspberry pi if it's any of help, because I have no clue what he is talking about.

quote:
"With the emulator working, I was able to get data from the ECU to display on the basic GUI.
However, I noticed that the GUI was extremely slow to update. After a fair amount of
debugging, I realized that the issue was that the ECU queries that I was making were
synchronous, and thus were blocking the UI. This meant that every time a query was made, the
program would block waiting for data and not update the GUI until the query finished. Luckily, I
was able to switch over to python-OBD’s asynchronous connection functionality which allowed
the UI to be updated on-the-fly. This asynchronous mode uses a threaded update loop that will
fire callbacks for the different queries as soon as new data is available from the ECU."


RE: obd lag/delay - nhadrian - 12-16-2020

Hi, I have the same issue, ELM327 OBDII receiver over Bluetooth, default startup codes in openauto_setup.ini.
Data is refreshed at 1 fps.

Here is a short video showing the lag, much more slower than in other preview videos.
https://youtu.be/Gj_53unYrNo

Looking forward of some solution or setup suggestion. 
Thank you in advance!

BR
Adrian


RE: obd lag/delay - BlueWave - 12-16-2020

(12-16-2020, 02:05 PM)nhadrian Wrote: Hi, I have the same issue, ELM327 OBDII receiver over Bluetooth, default startup codes in openauto_setup.ini.
Data is refreshed at 1 fps.

Here is a short video showing the lag, much more slower than in other preview videos.
https://youtu.be/Gj_53unYrNo

Looking forward of some solution or setup suggestion. 
Thank you in advance!

BR
Adrian

Refresh rate is mostly determined by performance of the ECU. Also OBD-II communication has quite low priority. You can try to adjust internal ELM327 timers (please have a look at ELM327 datasheet). You can also try to use Sport 2 dashboard type - it contains less gauges that may speed up a bit querying of the OBD PIDs.

In case of vehicles with slow OBD-II transmission we recommend to displays RPM value divided by 1000 (as for real instrument clusters) - it should give smoother feeling. More details https://bluewavestudio.io/community/showthread.php?tid=2046

[ObdGauge_4]
MinValue=0.0
MaxValue=8.0
Limit=6.2
Formula=getPidValue(4)/1000
Label=RPM
Precision=1

Does your vehicle report value of Load?