Why can I use Serial Monitor only on /dev/ttyUSB0?

Hello !

I’ve just connected two(2) ESP32 to my PC. The first device is on /dev/ttyUSB0, but the second one is nowhere to be found. I’ve tried from USB1 up to USB20 and PlatformIO couldn’t open any port.

First and second represent which device got connected first and second.

Is it possible to monitor multiple devices at a time ?
I should be able to at least set the Serial Terminal to monitor the device of my choice, right ?

I don’t want to disconnect the first device as I am still testing it and it has been running for the past week without any interruption.

I have now disconnected the first device, disconnected the second device.
Then I have connected the second device and I have no /dev/ttyUSB.
It won’t connect basically.
And this isn’t a PlatformIO issue anymore, but the above questions are still related.

So when you had both devices connected, did they both show up when you ran pio device list (or clicked ‘Devices’ in the Platform Project Tasks panel?

Multiple devices at the same time? Yes, if you have two environments setup, you can do it straight through the IDE, or you can run multiple instances of pio device monitor -p port in multiple terminals.

But it sounds like you have something wrong with the cable or device, since it’s not showing up at all. :cry:

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I think the cable was faulty. Even though it provided power, when I’ve changed it and closed VSC it appeared under /dev/ttyUSB0. I will try more cables and leave a feedback.

You may find out you have a ‘charge only’ cable in the mix… some of them only connect the outer two pins - VCC and GND - and either don’t connect the two data pins, or short them on the device end to trick the device into thinking it’s connected to a dedicated charger and can charge faster if it wants.