Due serial coms not working with serial monitor not open

okay,

so i'm working on calculation , time sensitive project, important things happen possible. because of trying learn how use native usb port upload codes , read serial data due.

i have run several problems.

1: when upload simple code increments counter , serialusb.println(counter); print counter value, counter not start @ zero, starts @ 19 times, starts in 20s somewhere times. seems random. if upload exact same code using programming port starts @ 0 correctly. attach code below.

2: both programming , native ports arduino not send serial data while serial monitor not open. have used both winforms app created, , free software called 'free device monitoring studio' try read data arduino should sending, both nothing when serial monitor closed. open serial monitor however, shows serial communication resume.

3: has #2, when ever close , re-open serial monitor, program running resets (or @ least kind of memory reset) because counter program mentioned above resets 0 when close , re-open serial monitor.

does have explanation this? have arduino running , sending serial data without having arduino ide's serial monitor open.

code: [select]


int counter=0;
void setup()
{
serialusb.begin(9600);
}

void loop()
{
serialusb.println(counter);
counter++;
delay(100);
}


hi soronemus,

i had faced issue similar on native usb port.

i found takes approximately 4500 msecs loop() run when programmed native usb port.
so added delay of 5000 msecs in setup(). not missing of prints.

i not know causes of delay.

but if below experiement can understand:

open arduino ide , flash code native usb port. open serial port (you see /dev/ttyacm* in ubuntu or /dev/com* in windows native usb port written in brackets). press reset button on arduino. see serial port lists. not able see native usb port enumerated there. take 4-5 seconds serial port detected.

if knows reason please let me know.

thanks,
sunny

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