[Free] Arduino USB Serial Extension



You can connect your Arduino to your phone with an OTG cable. Your phone must support OTG for this to work.


Probably Arduino sends some data in direction to the mobile as soon as it connects, if I try to establish the connection only with a 232 converter like a siliconlabs or an ftdi, your module “read” keeps giving the “* noyhing *” error. Please, can u mend it?


I’ll see my code for any problems


Thank U!!!

If you convert the call “read” to an event that is triggered when a data is detected, it would be very powerful.
Gracias Amigo!!!



and if yo can…


Hallo . i was not able to use the read () do you have any hint or example. compilation says that is an empty and don’t start application .


the app not starts after compilation because says it is empty how do you did?


have you received any hint about?


Can you show the blocks?


Sending something from a external device connected to the converter, in direction to the phone and then calling the read function. Im use a pc whit other usb rs232 and a serial terminal. But no is a solution. If use a clk to read and no have any byte in the in “buffer” keep the error.


when i push play button answer is bad argument to text .The operation Text cannot accept arguments :,[nothing]


Hello everyone,
I have this problem: “Runtime error Failed resolution of:Lcom/ftdi/j2xx/D2xxManager” .
I don’t need to communicate with Arduino, I only need to communicate via USB with FTDI breakout, like this app: https://play.google.com/store/apps/details?id=com.moonappdevelopers.usbterminal
I have tried this app and work very well with my phone (Huawei P9).
Wath I can do?
Thanks @pavi2410


extra test made with some corrections. when i am able to start all works fine also received frames . but at starting i always receive error for string also if i put one if to test if it is empty it not works may you help please ? have you a reading routine developed


defining better:

  • first time i start the app after the application requests if it can use usb the error of read nothing string arise always.
  • if i exit and restart app it work perfectly reading with a timer the rx buffer continuosly
  • if a exit another time and restart app ther error resumes until i not and detach and attach cable the error of [nothing] contents


Pavi designed the software for arduino. The arduino board contains a usb-232 converter, but the arduino microprocessor sends frames when connected. We are using the software connected only to a usb-232 converter. We have the problem because the “read” function waits for something in the input buffer.


I’m making a new version with lots of improvements. Also, I’m thinking of changing the library I use.


ok thanks for answer but i don’t understand why if i send some character at beginning, as i connect and power on arduino , it don’ t works . may be it wait for a longer frame?


ok thanks, waiting for it , do you have a way to turn around the problem ?


Tested today … Problem graph:

And then…

The problem is that if the “read” function is associated to a clock, causes the error when starting the application. Pavi, it would be better if the reading function were an event.


absolutely agree , according to what you say i did some changings not starting the clocked read as soon the app starts but only after i push a starting button. if you have the arduino externally powered it works as you say if not externally powered you have always an error also if you send a frame from arduino before the read ( i am working without your adapter but with the cable OTG) , if you do a reset button that close and reopen arduino interface it works. may please you explain me what is the action performed in suppresstoast and activatetoast ?