Open Serial Monitor on Mega 2560 & lose Serial Port on RPi B+


This afternoon whenever I open the Serial Monitor in the Arduino Mega 2560 I lose the Serial Port connection with the RPi B+. As soon as I close the Serial Monitor the Serial Port re-opens automatically and I have no problem uploading a different sketch. This morning everything worked fine.

I am sure this has happened before in the past using the RPi B+ and also an old desktop running Windows XP & I have given up for the day!

Any constructive thoughts welcome, Walter

You cannot open the arduino serial port twice simultaneously. That's why when you opened serial monitor you lost the RPi connection.

Thanks for your response, mart256, but the Serial Port should open automatically when the Arduino window is open & stay open when I open the Serial Monitor manually.

I know 'open' appears 4 times but I cannot think of any suitable words to replace 'open' this evening.

What is wrong. This morning, 10th February, there was no problem until I turned everything off correctly at 11.40. This afternoon I am having the same problem as yesterday afternoon and I have not moved the different parts at all. I have started noting the times when it works & when it does not !

Please note that yesterday evening, having turned the B+ off correctly around 20.00 & restarting at 21.00 there was no problem and I could retrieve the Serial.print(....) data from the Serial Monitor as I had been able to do in the morning ! It will be interesting to see if the it works again OK this evening. Will keep you posted.