How to Write to Serial Port with Flutter and Dart

[@ongpham585]

I get error "SerialPortError: Device or resource busy, errno = 16" when hot reload

[@rajgunaseelan44]

Thanks for the video. If possible, can you please make a video on how to receive data as well.

[@Chipsee]

I will ping you in this comment when that video releases :)

[@rajgunaseelan44]

@@Chipsee Thank you

[@Chipsee]

Here it is! ruclips.net/video/VQrIEv66WFE/видео.html, I hope you find it useful.

[@rajgunaseelan44]

@@Chipsee Thanks a lot. Super useful

[@bighits1606]

Upload video for read port data also, i have 4 port for read and transmit the data at same time.

[@Chipsee]

It's out, here you go: ruclips.net/video/VQrIEv66WFE/видео.html.
4 ports? You can have as many ports as you need, just change to `final port_2 = SerialPort('/dev/ttyS5')` or whatever your port name is in the OS.

[@bighits1606]

I want to transmit the data and read the data in same machine so i joined the transmit pin and read pin after this below errors
denied { getattr } for path="/dev/ttysWK3" dev="tmpfs" ino=6666 scontext=u:r:untrusted_app:s0:c512,c768 tcontext=u:object_r:device:s0 tclass=chr_file permissive=1
denied { read write }
denied { open }
if the app closed while the port is open and you open again so the error we get is resource is busy - temp solution is restart the device@@Chipsee

[@Chipsee]

I've seen this issue happen multiple times! "Resource is busy". Later I found a way to solve this is to add some delay before init the port.
For example, in initState(), you _initPort(), but instead of _initPort() immediately, you add a timer of 500ms delay: timer = Timer(const Duration(milliseconds: 500), () => _initPort());
And when the widget is deactivate(), you @overried the deactivate(), and add
@override
void deactivate() {
port.close();
port.dispose();
timer.cancel();
super.deactivate();
}
You can try these and see if it helps. Take a look at the github repo, I open sourced it.

[@Chipsee]

Repo: github.com/printfinn/chipsee_serial_port_flutter

[@cristianvelez-g4l]

Hello, Using the git code, I get this error.
No such file or directory, errno = 2
Thank u

[@Chipsee]

Did you change the port to your port?
On the Chipsee RS485_4, it's /dev/ttyS4.
Did you change this to your port? For example /dev/ttyAMA0? Or /dev/ttyUSB0 etc?

[@Hariharan-t3y]

Execution failed for task ':flutter_libserialport:buildCMakeDebug[arm64-v8a]'.

[@Chipsee]

Check this github.com/jpnurmi/flutter_libserialport/issues/81. Or check my source code: github.com/printfinn/chipsee_serial_port_flutter

[@Hariharan-t3y]

Permission denied, errno = 13

[@Chipsee]

I don't remember I encountered anything like this while developing. What device are you using? Are you using a Chipsee Android panel PC?

[@ЕвгенийКадышев-ж6я]

I also get this error, I tried to connect the arduino to android.

[@Chipsee]

Can you try my source code on your device and see if it happens? github.com/printfinn/chipsee_serial_port_flutter

[@robologautomation1801]

got same error please support

[@robologautomation1801]

@@Chipsee got the same error, used your source code but not working