Connection two devices

Tell me please. I have two connections in the dashboard, OBD2 and Arduino, if one of them is disconnected, then two connections disappear at once and the connection to two controllers is lit at the bottom right. What am I doing wrong, how can I fix it?

All connections are implemented to be independent to each other, so it ‘should’ work.

Give little bit more details:

  • What OS? (Windows, Android, iOS, Linux)
  • Connection Types? (USB, Serial, Bluetooth, BLE)

The program is installed on Adnroid tablet (android 10), both connections via USB.

  1. usb adapter ELM327
  2. arduino via usb

You have an Android tablet with 2 USB connections, or are you using a USB hub of some sort?

I know that some USB hubs send the USB Disconnected message for all connected devices when one is disconnected, that could be your issue.

In the tablet, or rather in the Android radio, there are three USB inputs, I do not use the hub. Teyes CC3

if adduino and ELM 327 have same usb CHIP - you get problem (CH340)
need one device CH340 and other resolid on the new chip PL…

arduino on CH340 chip
elm327 on PL2303 chip

I have two adruino modules connected to each other via a can bus (mpc2515). I want to transfer data from the arduino via the can bus of the car to the dashboard via ELM327. When choosing a connection, I use the standard settings (Generic SAE-Compatible vehicle). Where can I get this standard description file (XML)? I want to add to it the data that I transmit over the CAN bus from the arduino. And is it possible to add to this file the protocol by which I connect to the ECU (ISO-15765-4 CAN(29bit ID, 250kbaub), this protocol is simply not in the list of suggested ones.

RealDash-extras/OBD2 at master · janimm/RealDash-extras (

And how do I add my TargetID and PID so that it is displayed in RealDash?

Add new line to ‘rotation’ section. See how they are done in default XML.