Serial Port Communication

Hello,

I am working with Arduino AtMEGA 1284P for a projet and i have a real problem about Serial port Communication.
In fact, there is a serial port perturbation when the serial monitor is opening.
Even if there is no data in the serial port, as soon as i launch a serial monitor, it shows me data whom i didn' t khow origins.

Please help me to understand this in order to work out the problem.
Thanks!

In fact, there is a serial port perturbation when the serial monitor is opening.

Yup, that's standard.

Post your code, post your observations.

Dear, AWOL, may I hook into your dialogue and ask you to help me understand a strange behavior of my board Arduino Leonardo?
The Question is: Why the code below does not output to port monitor window anything?

void setup() { Serial.begin(9600); while(!Serial);}

void loop ()
{
for ( int i=0; i<10;i++)
{
Serial.write ("any text...");
delay (10000);
}
}

I expect to see at least one string within 10 seconds... What's wrong?

Can you share screen shot of Serial monitor

since you using AtMEGA 1284P WHich arduino controller is using it???

use simple code

void setup()
{

Serial.begin(9600);
}

void loop()
{

Serial.write("welcome to arduino");
delay(1000);

}

Good evening AMPS-N.
Thank you for helping me.
I've got Leonardo board with chip marked as MEGA32U4.
There two screenshots below to show that Arduino installed properly in OS (See both OS and IDE detected Leonardo on COM4). After uploading code Leonardo switched off and back again on COM4.
But there's no output at all.

Excuse me for Russian chars on Screenshot... I translated for You text within IDE. And apply some notes...

https://yadi.sk/i/iJXH8mbudiRp9

Try
Serial.print("welcome to arduino");

instead of

Serial.write("welcome to arduino");

Hello, CrossRoads.
I've been corrected lil bit erlier. Thank you. But there's no output anyway... I have had checked...

Maybe It helps to help me the voltage metered on pin13

I mean it's quite strange, like any code runing... Isn't it?

video-2014-12-30-23-32-27.mpg (649 KB)

First thing you haven't upload the code i told to try.

Here i am attaching driver zip file .Unzip in arduino folder replace with this. Reinstall the driver manually.

drivers.zip (1.19 MB)

First of all... Happy New year to everyone. You know this is a most favorit holiday in Russia.
AMPS-N. I faced some troubles with Arduino... Didn't expect it's too complicated to start programming ::slight_smile: . I will follow you recomendations and will post a lil bit later...