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By frogl
#200322
Hello,
i flashed my board with arduino and after this, the COM port in Win is lost. I tried another cable and devices.
I think I know what happens but not what I can do to repair it.

What happens:
I flashed a lot of code and it works. But since the last change in the code the size is to big and the ATMEGA32u4 cannot handle the USB communication because he has only one processor.
With a knew pro micro board all ist good. After the flash I have the same issue that the COM port is lost in Windows.
After while/after flashing with arduino I get this message (GERMAN sorry):
Code: Select all
Der Sketch verwendet 23226 Bytes (81%) des Programmspeicherplatzes. Das Maximum sind 28672 Bytes.
Globale Variablen verwenden 2149 Bytes (83%) des dynamischen Speichers, 411 Bytes für lokale Variablen verbleiben. Das Maximum sind 2560 Bytes.
Wenig Arbeitsspeicher verfügbar, es können Stabilitätsprobleme auftreten.

processing.app.SerialException: Fehler beim Öffnen des seriellen Ports "COM7".
	at processing.app.Serial.<init>(Serial.java:139)
	at processing.app.Serial.<init>(Serial.java:78)
	at processing.app.SerialMonitor$4.<init>(SerialMonitor.java:101)
	at processing.app.SerialMonitor.open(SerialMonitor.java:101)
	at processing.app.AbstractMonitor.resume(AbstractMonitor.java:110)
	at processing.app.Editor.resumeOrCloseSerialMonitor(Editor.java:2199)
	at processing.app.Editor.access$2200(Editor.java:79)
	at processing.app.Editor$DefaultExportHandler.run(Editor.java:2177)
	at java.lang.Thread.run(Thread.java:745)
How can I flash blank programm or a smaller one, that the USB communication works and the COM port is given in Windows?

Thanks for your help!
By znib
#200388
I accidentally had the Processor in the Arduino IDE set to "ATmega32U4 (3.3V, 8MHz)" and flashed two 5V/16MHz Arduino pro micros. Now I have the exact same effect like frogl, Windows doesn't recognize these two Pro Micro's anymore, the COM port doesn't show up, so I can not re-programm them anymore....

Is there a way to re-cover these two Pro Micros?