[Free] Arduino USB Serial Extension



I think i found the following solution, maybe you can try:

“ upon further review, digging through the Arduino source for the USB serial code, it looks to me like the DTR check is at line 224 (first line of size_t Serial_::write(const uint8_t *buffer, size_t size) ). I’m not terribly optimistic about disabling it (you’ll probably flood some buffer), but it might be worth a try.”

from https://electronics.stackexchange.com/questions/128839/how-to-get-32u4-arduino-to-ignore-dtr-for-usb-serial


this post is too old, when I check the link , I found the newest code link is : https://github.com/arduino/ArduinoCore-avr/blob/5755ddea49fa69d6c505c772ebee5af5078e2ebf/cores/arduino/CDC.cpp#L232

so maybe you can try remove " if (_usbLineInfo.lineState > 0) " statement. like this:


Hello, I have exactly the same problem as you, I tried all the versions of this extension that I could find,
In addition, I tried on 2 smartphones (android 4.2 and 8) but nothing helps, never this message request “USB authorization”

Have you since resolved this problem?

Thank you in advance :wink:


Hi, does this extension only work on Arduino boards? What if I want to create an app like Serial Communication RS232 in the PlayStore (https://play.google.com/store/apps/details?id=co.com.serialCommunicationRS232&hl=en_US), would the extension still work?

I really need such USB serial extension very much. Appreciate if anyone could reply and help.


I have the same issue. Can someone point where the code is located? The issue can be solved by adding the FTDI android drivers to the extension. @pavi2410 is it possible to add the updated Physicaloid library (https://github.com/ideniden/PhysicaloidLibrary) as suggested by @Maxim_Ibragimov?


i want to read arduino serial data in android pls help me anyone.