OTG problem with Clone NANO Arduino

Having problems with app inventor communicating via OTG to a clone Nano.
Everything works OK when I use the excellent Kai-morich.de/android app.
This Kai app is great for fault-finding, and the source code is available (but it is not written in app inventor code).

This proves that the Nokia settings, OTG cable, and my nano sketch all work OK.
But when I use any of the available OTG apps (Serial USB Arduino, OTG_cable_to_Arduino etc) The nano is not recognized by the app.

I think a genuine Arduino NANO with FTDI USB would work, as I have a genuine UNO that works and a clone UNO using a CH34 USB that fails.

But as I have over 20 clone nanos this is my preferred option.
Any ideas...

The USB terminal you linked to is based on the same libraries on which this extension was created:

This topic provides links to github where you will find aix files and a sample app in aia format.

I have the same problem... ie clone with ch340 works with USB serial application but not with MIT app inventor.
.. but I do not understand your reply at all. I do not get a Java error...
Is there a way to select the serial port ??
thank you

The original UNO uses an 16U2 programmed as an usb-serial converter using CDC-ACM protocol for USB communication. The specific runtime error depends on a missing FTDI D2xx library for FT232 USB-serial converter that must be included in the app. It is not open source or free to use as you like.

CH340 is another USB-serial converter but can not be use with the built in serial component.

That is why I corrected bugs, refactored, added more adapters and extended functions. This is now an extension SerialOTG that can be found at https://github.com/rkl099/Appinventor-SerialOTG It will work with most Arduino:s and most external USB-serial converters.

I think the referenced thread will fully explain the background. You can also search for “serial” in the forum for some more references.

1 Like

Hi rkl009
thank you for your reply.
It works great !
I learned that my setup was working by getting and running the SerialOTG.apk application...
And got the extension com.SerialOTG.aix into my program (Palette-extension-import extension), my appinventor program now works.
thanks again... :slight_smile: